From d1fa945261a30616c5e3557d1a9fc18f3482af30 Mon Sep 17 00:00:00 2001
From: Wesley Wigham <wewigham@microsoft.com>
Date: Fri, 11 Mar 2022 10:36:00 -0800
Subject: [PATCH] Add moduleDetection compiler flag to allow for changing how
 modules are parsed (#47495)

* Add moduleDetection compiler flag to allow for changing how modules are parsed

The default setting is 'auto', where JSX containing files under react-jsx and react-jsxdev are
always parsed as modules, and esm-format files under module: node12+ are always parsed as modules,
in addition to the 'legacy' detection mode's conditions for other files. (Declaration files are exempt from
these new conditions)

The 'legacy' mode preserves TS's behavior prior to the introduction of this flag - a file is
parsed as a module if it contains an import, export, or import.meta expression.

In addition, there is a 'force' mode that forces all non-declaration files to be parsed as modules.
(Declaration files are still only modules if they contain a top-level import or export.)

This technically breaks the parser API, but it's kinda-sorta backwards compatible so long
as you don't need the functionality associated with more recent compiler flags.

* Fix post-merge lint

* Rename function

* Update default value documentation

* PR feedback

* Fix lint and typo
---
 src/compiler/commandLineParser.ts             |  12 ++
 src/compiler/core.ts                          |  10 +-
 src/compiler/diagnosticMessages.json          |   8 +
 src/compiler/parser.ts                        | 157 +++++++++++-------
 src/compiler/program.ts                       |  31 ++--
 src/compiler/resolutionCache.ts               |   3 +-
 src/compiler/types.ts                         |  36 +++-
 src/compiler/utilities.ts                     |  61 +++++++
 src/compiler/watch.ts                         |   4 +-
 src/compiler/watchPublic.ts                   |   4 +-
 src/harness/fourslashImpl.ts                  |  12 +-
 src/harness/harnessLanguageService.ts         |  18 ++
 src/server/project.ts                         |   5 +
 src/services/documentRegistry.ts              |  54 ++++--
 src/services/refactors/moveToNewFile.ts       |   2 +-
 src/services/services.ts                      |  27 ++-
 src/services/suggestionDiagnostics.ts         |   2 +-
 src/services/transpile.ts                     |  39 +++--
 src/services/types.ts                         |  11 +-
 src/services/utilities.ts                     |   2 +-
 src/testRunner/compilerRunner.ts              |   1 +
 .../unittests/services/extract/helpers.ts     |   2 +
 .../unittests/services/hostNewLineSupport.ts  |   6 +
 .../unittests/services/languageService.ts     |   4 +
 .../baselines/reference/APISample_watcher.js  |   6 +-
 .../reference/api/tsserverlibrary.d.ts        |  73 ++++++--
 tests/baselines/reference/api/typescript.d.ts |  73 ++++++--
 ...,module=commonjs,moduledetection=auto).js} |   0
 ...le=commonjs,moduledetection=auto).symbols} |   0
 ...dule=commonjs,moduledetection=auto).types} |   0
 ...,module=commonjs,moduledetection=force).js |  46 +++++
 ...e=commonjs,moduledetection=force).symbols} |   0
 ...ule=commonjs,moduledetection=force).types} |   0
 ...odule=commonjs,moduledetection=legacy).js} |   0
 ...=commonjs,moduledetection=legacy).symbols} |   0
 ...ule=commonjs,moduledetection=legacy).types |  30 ++++
 ...rve,module=system,moduledetection=auto).js |  44 +++++
 ...dule=system,moduledetection=auto).symbols} |   0
 ...,module=system,moduledetection=auto).types |  30 ++++
 ...ve,module=system,moduledetection=force).js |  54 ++++++
 ...ule=system,moduledetection=force).symbols} |   0
 ...module=system,moduledetection=force).types |  30 ++++
 ...e,module=system,moduledetection=legacy).js |  44 +++++
 ...le=system,moduledetection=legacy).symbols} |   0
 ...odule=system,moduledetection=legacy).types |  30 ++++
 ...commonjs,moduledetection=auto).errors.txt} |   0
 ...,module=commonjs,moduledetection=auto).js} |   0
 ...le=commonjs,moduledetection=auto).symbols} |   0
 ...dule=commonjs,moduledetection=auto).types} |   0
 ...ommonjs,moduledetection=force).errors.txt} |   0
 ...,module=commonjs,moduledetection=force).js |  33 ++++
 ...e=commonjs,moduledetection=force).symbols} |   0
 ...ule=commonjs,moduledetection=force).types} |   0
 ...ommonjs,moduledetection=legacy).errors.txt |  26 +++
 ...odule=commonjs,moduledetection=legacy).js} |   0
 ...e=commonjs,moduledetection=legacy).symbols |  27 +++
 ...le=commonjs,moduledetection=legacy).types} |   0
 ...le=system,moduledetection=auto).errors.txt |  26 +++
 ...act,module=system,moduledetection=auto).js |  31 ++++
 ...odule=system,moduledetection=auto).symbols |  27 +++
 ...module=system,moduledetection=auto).types} |   0
 ...e=system,moduledetection=force).errors.txt |  26 +++
 ...ct,module=system,moduledetection=force).js |  41 +++++
 ...dule=system,moduledetection=force).symbols |  27 +++
 ...odule=system,moduledetection=force).types} |   0
 ...=system,moduledetection=legacy).errors.txt |  26 +++
 ...t,module=system,moduledetection=legacy).js |  31 ++++
 ...ule=system,moduledetection=legacy).symbols |  27 +++
 ...dule=system,moduledetection=legacy).types} |   0
 ...commonjs,moduledetection=auto).errors.txt} |   0
 ...x,module=commonjs,moduledetection=auto).js |  34 ++++
 ...ule=commonjs,moduledetection=auto).symbols |  27 +++
 ...odule=commonjs,moduledetection=auto).types |  30 ++++
 ...commonjs,moduledetection=force).errors.txt |  39 +++++
 ...,module=commonjs,moduledetection=force).js |  34 ++++
 ...le=commonjs,moduledetection=force).symbols |  27 +++
 ...dule=commonjs,moduledetection=force).types |  30 ++++
 ...ommonjs,moduledetection=legacy).errors.txt |  39 +++++
 ...odule=commonjs,moduledetection=legacy).js} |   0
 ...e=commonjs,moduledetection=legacy).symbols |  27 +++
 ...ule=commonjs,moduledetection=legacy).types |  30 ++++
 ...e=system,moduledetection=auto).errors.txt} |   0
 ...jsx,module=system,moduledetection=auto).js |  45 +++++
 ...odule=system,moduledetection=auto).symbols |  27 +++
 ...,module=system,moduledetection=auto).types |  30 ++++
 ...e=system,moduledetection=force).errors.txt |  39 +++++
 ...sx,module=system,moduledetection=force).js |  45 +++++
 ...dule=system,moduledetection=force).symbols |  27 +++
 ...module=system,moduledetection=force).types |  30 ++++
 ...=system,moduledetection=legacy).errors.txt |  39 +++++
 ...,module=system,moduledetection=legacy).js} |   0
 ...ule=system,moduledetection=legacy).symbols |  27 +++
 ...odule=system,moduledetection=legacy).types |  30 ++++
 ...commonjs,moduledetection=auto).errors.txt} |   0
 ...v,module=commonjs,moduledetection=auto).js |  35 ++++
 ...ule=commonjs,moduledetection=auto).symbols |  27 +++
 ...odule=commonjs,moduledetection=auto).types |  30 ++++
 ...commonjs,moduledetection=force).errors.txt |  39 +++++
 ...,module=commonjs,moduledetection=force).js |  35 ++++
 ...le=commonjs,moduledetection=force).symbols |  27 +++
 ...dule=commonjs,moduledetection=force).types |  30 ++++
 ...ommonjs,moduledetection=legacy).errors.txt |  39 +++++
 ...odule=commonjs,moduledetection=legacy).js} |   0
 ...e=commonjs,moduledetection=legacy).symbols |  27 +++
 ...ule=commonjs,moduledetection=legacy).types |  30 ++++
 ...e=system,moduledetection=auto).errors.txt} |   0
 ...dev,module=system,moduledetection=auto).js |  46 +++++
 ...odule=system,moduledetection=auto).symbols |  27 +++
 ...,module=system,moduledetection=auto).types |  30 ++++
 ...e=system,moduledetection=force).errors.txt |  39 +++++
 ...ev,module=system,moduledetection=force).js |  46 +++++
 ...dule=system,moduledetection=force).symbols |  27 +++
 ...module=system,moduledetection=force).types |  30 ++++
 ...=system,moduledetection=legacy).errors.txt |  39 +++++
 ...,module=system,moduledetection=legacy).js} |   0
 ...ule=system,moduledetection=legacy).symbols |  27 +++
 ...odule=system,moduledetection=legacy).types |  30 ++++
 .../moduleResolutionWithoutExtension5.js      |   1 +
 .../moduleDetection/tsconfig.json             |   5 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../tsconfig.json                             |   1 +
 .../declarationDir-is-specified.js            |   1 +
 ...-outDir-and-declarationDir-is-specified.js |   1 +
 .../when-outDir-is-specified.js               |   1 +
 .../with-outFile.js                           |   1 +
 ...e-is-specified-with-declaration-enabled.js |   1 +
 .../without-outDir-or-outFile-is-specified.js |   1 +
 .../reference/tsxReactEmit8(jsx=react-jsx).js |   1 +
 .../tsxReactEmit8(jsx=react-jsxdev).js        |   1 +
 ...nvalidType(jsx=react-jsx,target=es2015).js |   1 +
 ...dType(jsx=react-jsx,target=es2015).symbols |   8 -
 ...lidType(jsx=react-jsx,target=es2015).types |  24 +--
 ...enInvalidType(jsx=react-jsx,target=es5).js |  11 +-
 ...alidType(jsx=react-jsx,target=es5).symbols |   8 -
 ...nvalidType(jsx=react-jsx,target=es5).types |  24 +--
 tests/cases/compiler/APISample_watcher.ts     |   2 +
 .../commentsOnJSXExpressionsArePreserved.tsx  |   1 +
 144 files changed, 2534 insertions(+), 203 deletions(-)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).js => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).js} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).symbols => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).symbols} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).types => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).types} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).js
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).symbols => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).symbols} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).types => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).types} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).js => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).js} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).symbols => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).symbols} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).js
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=system).symbols => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).symbols} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).js
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).symbols => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).symbols} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).js
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).symbols => commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).symbols} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).types
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).errors.txt => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).errors.txt} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).js => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).js} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).symbols => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).symbols} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).types => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).types} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=system).errors.txt => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).errors.txt} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).js
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).symbols => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).symbols} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=system).types => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).types} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).errors.txt
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react,module=system).js => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).js} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).symbols
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).types => commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).types} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).symbols
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).types => commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).types} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).symbols
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).types => commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).types} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).symbols
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).types => commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).types} (100%)
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).errors.txt => commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).errors.txt} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).errors.txt
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).js => commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).js} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).types
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).errors.txt => commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).errors.txt} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).errors.txt
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).js => commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).js} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).types
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).errors.txt => commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).errors.txt} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).errors.txt
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).js => commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).js} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).types
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).errors.txt => commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).errors.txt} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).errors.txt
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).js
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).types
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).errors.txt
 rename tests/baselines/reference/{commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).js => commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).js} (100%)
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).symbols
 create mode 100644 tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).types
 create mode 100644 tests/baselines/reference/showConfig/Shows tsconfig for single option/moduleDetection/tsconfig.json

diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 1cf4b9724d7..757ae3bba25 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -1241,6 +1241,18 @@ namespace ts {
             category: Diagnostics.Editor_Support,
 
         },
+        {
+            name: "moduleDetection",
+            type: new Map(getEntries({
+                auto: ModuleDetectionKind.Auto,
+                legacy: ModuleDetectionKind.Legacy,
+                force: ModuleDetectionKind.Force,
+            })),
+            affectsModuleResolution: true,
+            description: Diagnostics.Control_what_method_is_used_to_detect_module_format_JS_files,
+            category: Diagnostics.Language_and_Environment,
+            defaultValueDescription: Diagnostics.auto_Colon_Treat_files_with_imports_exports_import_meta_jsx_with_jsx_Colon_react_jsx_or_esm_format_with_module_Colon_node12_as_modules,
+        }
     ];
 
     /* @internal */
diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index cceaa2abd50..b9adfb94fc8 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -2156,14 +2156,16 @@ namespace ts {
         return (arg: T) => f(arg) && g(arg);
     }
 
-    export function or<T extends unknown[]>(...fs: ((...args: T) => boolean)[]): (...args: T) => boolean {
+    export function or<T extends unknown[], U>(...fs: ((...args: T) => U)[]): (...args: T) => U {
         return (...args) => {
+            let lastResult: U;
             for (const f of fs) {
-                if (f(...args)) {
-                    return true;
+                lastResult = f(...args);
+                if (lastResult) {
+                    return lastResult;
                 }
             }
-            return false;
+            return lastResult!;
         };
     }
 
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index f211d7aeb20..387d7123beb 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -1449,6 +1449,14 @@
         "category": "Error",
         "code": 1474
     },
+    "Control what method is used to detect module-format JS files.": {
+        "category": "Message",
+        "code": 1475
+    },
+    "\"auto\": Treat files with imports, exports, import.meta, jsx (with jsx: react-jsx), or esm format (with module: node12+) as modules.": {
+        "category": "Message",
+        "code": 1476
+    },
 
     "The types of '{0}' are incompatible between these types.": {
         "category": "Error",
diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index 8266db7f40c..898f50c475e 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -60,6 +60,41 @@ namespace ts {
             text.charCodeAt(start + 3) !== CharacterCodes.slash;
     }
 
+    /*@internal*/
+    export function isFileProbablyExternalModule(sourceFile: SourceFile) {
+        // Try to use the first top-level import/export when available, then
+        // fall back to looking for an 'import.meta' somewhere in the tree if necessary.
+        return forEach(sourceFile.statements, isAnExternalModuleIndicatorNode) ||
+            getImportMetaIfNecessary(sourceFile);
+    }
+
+    function isAnExternalModuleIndicatorNode(node: Node) {
+        return hasModifierOfKind(node, SyntaxKind.ExportKeyword)
+            || isImportEqualsDeclaration(node) && isExternalModuleReference(node.moduleReference)
+            || isImportDeclaration(node)
+            || isExportAssignment(node)
+            || isExportDeclaration(node) ? node : undefined;
+    }
+
+    function getImportMetaIfNecessary(sourceFile: SourceFile) {
+        return sourceFile.flags & NodeFlags.PossiblyContainsImportMeta ?
+            walkTreeForImportMeta(sourceFile) :
+            undefined;
+    }
+
+    function walkTreeForImportMeta(node: Node): Node | undefined {
+        return isImportMeta(node) ? node : forEachChild(node, walkTreeForImportMeta);
+    }
+
+    /** Do not use hasModifier inside the parser; it relies on parent pointers. Use this instead. */
+    function hasModifierOfKind(node: Node, kind: SyntaxKind) {
+        return some(node.modifiers, m => m.kind === kind);
+    }
+
+    function isImportMeta(node: Node): boolean {
+        return isMetaProperty(node) && node.keywordToken === SyntaxKind.ImportKeyword && node.name.escapedText === "meta";
+    }
+
     /**
      * Invokes a callback for each child of the given node. The 'cbNode' callback is invoked for all child nodes
      * stored in properties. If a 'cbNodes' callback is specified, it is invoked for embedded arrays; otherwise,
@@ -642,17 +677,46 @@ namespace ts {
         }
     }
 
-    export function createSourceFile(fileName: string, sourceText: string, languageVersion: ScriptTarget, setParentNodes = false, scriptKind?: ScriptKind): SourceFile {
+    export interface CreateSourceFileOptions {
+        languageVersion: ScriptTarget;
+        /**
+         * Controls the format the file is detected as - this can be derived from only the path
+         * and files on disk, but needs to be done with a module resolution cache in scope to be performant.
+         * This is usually `undefined` for compilations that do not have `moduleResolution` values of `node12` or `nodenext`.
+         */
+        impliedNodeFormat?: ModuleKind.ESNext | ModuleKind.CommonJS;
+        /**
+         * Controls how module-y-ness is set for the given file. Usually the result of calling
+         * `getSetExternalModuleIndicator` on a valid `CompilerOptions` object. If not present, the default
+         * check specified by `isFileProbablyExternalModule` will be used to set the field.
+         */
+        setExternalModuleIndicator?: (file: SourceFile) => void;
+    }
+
+    function setExternalModuleIndicator(sourceFile: SourceFile) {
+        sourceFile.externalModuleIndicator = isFileProbablyExternalModule(sourceFile);
+    }
+
+    export function createSourceFile(fileName: string, sourceText: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, setParentNodes = false, scriptKind?: ScriptKind): SourceFile {
         tracing?.push(tracing.Phase.Parse, "createSourceFile", { path: fileName }, /*separateBeginAndEnd*/ true);
         performance.mark("beforeParse");
         let result: SourceFile;
 
         perfLogger.logStartParseSourceFile(fileName);
+        const {
+            languageVersion,
+            setExternalModuleIndicator: overrideSetExternalModuleIndicator,
+            impliedNodeFormat: format
+        } = typeof languageVersionOrOptions === "object" ? languageVersionOrOptions : ({ languageVersion: languageVersionOrOptions } as CreateSourceFileOptions);
         if (languageVersion === ScriptTarget.JSON) {
-            result = Parser.parseSourceFile(fileName, sourceText, languageVersion, /*syntaxCursor*/ undefined, setParentNodes, ScriptKind.JSON);
+            result = Parser.parseSourceFile(fileName, sourceText, languageVersion, /*syntaxCursor*/ undefined, setParentNodes, ScriptKind.JSON, noop);
         }
         else {
-            result = Parser.parseSourceFile(fileName, sourceText, languageVersion, /*syntaxCursor*/ undefined, setParentNodes, scriptKind);
+            const setIndicator = format === undefined ? overrideSetExternalModuleIndicator : (file: SourceFile) => {
+                file.impliedNodeFormat = format;
+                return (overrideSetExternalModuleIndicator || setExternalModuleIndicator)(file);
+            };
+            result = Parser.parseSourceFile(fileName, sourceText, languageVersion, /*syntaxCursor*/ undefined, setParentNodes, scriptKind, setIndicator);
         }
         perfLogger.logStopParseSourceFile();
 
@@ -851,7 +915,7 @@ namespace ts {
         // attached to the EOF token.
         let parseErrorBeforeNextFinishedNode = false;
 
-        export function parseSourceFile(fileName: string, sourceText: string, languageVersion: ScriptTarget, syntaxCursor: IncrementalParser.SyntaxCursor | undefined, setParentNodes = false, scriptKind?: ScriptKind): SourceFile {
+        export function parseSourceFile(fileName: string, sourceText: string, languageVersion: ScriptTarget, syntaxCursor: IncrementalParser.SyntaxCursor | undefined, setParentNodes = false, scriptKind?: ScriptKind, setExternalModuleIndicatorOverride?: (file: SourceFile) => void): SourceFile {
             scriptKind = ensureScriptKind(fileName, scriptKind);
             if (scriptKind === ScriptKind.JSON) {
                 const result = parseJsonText(fileName, sourceText, languageVersion, syntaxCursor, setParentNodes);
@@ -867,7 +931,7 @@ namespace ts {
 
             initializeState(fileName, sourceText, languageVersion, syntaxCursor, scriptKind);
 
-            const result = parseSourceFileWorker(languageVersion, setParentNodes, scriptKind);
+            const result = parseSourceFileWorker(languageVersion, setParentNodes, scriptKind, setExternalModuleIndicatorOverride || setExternalModuleIndicator);
 
             clearState();
 
@@ -955,7 +1019,7 @@ namespace ts {
             }
 
             // Set source file so that errors will be reported with this file name
-            const sourceFile = createSourceFile(fileName, ScriptTarget.ES2015, ScriptKind.JSON, /*isDeclaration*/ false, statements, endOfFileToken, sourceFlags);
+            const sourceFile = createSourceFile(fileName, ScriptTarget.ES2015, ScriptKind.JSON, /*isDeclaration*/ false, statements, endOfFileToken, sourceFlags, noop);
 
             if (setParentNodes) {
                 fixupParentReferences(sourceFile);
@@ -1039,7 +1103,7 @@ namespace ts {
             topLevel = true;
         }
 
-        function parseSourceFileWorker(languageVersion: ScriptTarget, setParentNodes: boolean, scriptKind: ScriptKind): SourceFile {
+        function parseSourceFileWorker(languageVersion: ScriptTarget, setParentNodes: boolean, scriptKind: ScriptKind, setExternalModuleIndicator: (file: SourceFile) => void): SourceFile {
             const isDeclarationFile = isDeclarationFileName(fileName);
             if (isDeclarationFile) {
                 contextFlags |= NodeFlags.Ambient;
@@ -1054,7 +1118,7 @@ namespace ts {
             Debug.assert(token() === SyntaxKind.EndOfFileToken);
             const endOfFileToken = addJSDocComment(parseTokenNode<EndOfFileToken>());
 
-            const sourceFile = createSourceFile(fileName, languageVersion, scriptKind, isDeclarationFile, statements, endOfFileToken, sourceFlags);
+            const sourceFile = createSourceFile(fileName, languageVersion, scriptKind, isDeclarationFile, statements, endOfFileToken, sourceFlags, setExternalModuleIndicator);
 
             // A member of ReadonlyArray<T> isn't assignable to a member of T[] (and prevents a direct cast) - but this is where we set up those members so they can be readonly in the future
             processCommentPragmas(sourceFile as {} as PragmaContext, sourceText);
@@ -1213,28 +1277,42 @@ namespace ts {
             setParentRecursive(rootNode, /*incremental*/ true);
         }
 
-        function createSourceFile(fileName: string, languageVersion: ScriptTarget, scriptKind: ScriptKind, isDeclarationFile: boolean, statements: readonly Statement[], endOfFileToken: EndOfFileToken, flags: NodeFlags): SourceFile {
+        function createSourceFile(
+            fileName: string,
+            languageVersion: ScriptTarget,
+            scriptKind: ScriptKind,
+            isDeclarationFile: boolean,
+            statements: readonly Statement[],
+            endOfFileToken: EndOfFileToken,
+            flags: NodeFlags,
+            setExternalModuleIndicator: (sourceFile: SourceFile) => void): SourceFile {
             // code from createNode is inlined here so createNode won't have to deal with special case of creating source files
             // this is quite rare comparing to other nodes and createNode should be as fast as possible
             let sourceFile = factory.createSourceFile(statements, endOfFileToken, flags);
             setTextRangePosWidth(sourceFile, 0, sourceText.length);
-            setExternalModuleIndicator(sourceFile);
+            setFields(sourceFile);
 
             // If we parsed this as an external module, it may contain top-level await
             if (!isDeclarationFile && isExternalModule(sourceFile) && sourceFile.transformFlags & TransformFlags.ContainsPossibleTopLevelAwait) {
                 sourceFile = reparseTopLevelAwait(sourceFile);
+                setFields(sourceFile);
             }
 
-            sourceFile.text = sourceText;
-            sourceFile.bindDiagnostics = [];
-            sourceFile.bindSuggestionDiagnostics = undefined;
-            sourceFile.languageVersion = languageVersion;
-            sourceFile.fileName = fileName;
-            sourceFile.languageVariant = getLanguageVariant(scriptKind);
-            sourceFile.isDeclarationFile = isDeclarationFile;
-            sourceFile.scriptKind = scriptKind;
-
             return sourceFile;
+
+            function setFields(sourceFile: SourceFile) {
+                sourceFile.text = sourceText;
+                sourceFile.bindDiagnostics = [];
+                sourceFile.bindSuggestionDiagnostics = undefined;
+                sourceFile.languageVersion = languageVersion;
+                sourceFile.fileName = fileName;
+                sourceFile.languageVariant = getLanguageVariant(scriptKind);
+                sourceFile.isDeclarationFile = isDeclarationFile;
+                sourceFile.scriptKind = scriptKind;
+
+                setExternalModuleIndicator(sourceFile);
+                sourceFile.setExternalModuleIndicator = setExternalModuleIndicator;
+            }
         }
 
         function setContextFlag(val: boolean, flag: NodeFlags) {
@@ -7575,41 +7653,6 @@ namespace ts {
             return withJSDoc(finishNode(node, pos), hasJSDoc);
         }
 
-        function setExternalModuleIndicator(sourceFile: SourceFile) {
-            // Try to use the first top-level import/export when available, then
-            // fall back to looking for an 'import.meta' somewhere in the tree if necessary.
-            sourceFile.externalModuleIndicator =
-                    forEach(sourceFile.statements, isAnExternalModuleIndicatorNode) ||
-                    getImportMetaIfNecessary(sourceFile);
-        }
-
-        function isAnExternalModuleIndicatorNode(node: Node) {
-            return hasModifierOfKind(node, SyntaxKind.ExportKeyword)
-                || isImportEqualsDeclaration(node) && ts.isExternalModuleReference(node.moduleReference)
-                || isImportDeclaration(node)
-                || isExportAssignment(node)
-                || isExportDeclaration(node) ? node : undefined;
-        }
-
-        function getImportMetaIfNecessary(sourceFile: SourceFile) {
-            return sourceFile.flags & NodeFlags.PossiblyContainsImportMeta ?
-                walkTreeForExternalModuleIndicators(sourceFile) :
-                undefined;
-        }
-
-        function walkTreeForExternalModuleIndicators(node: Node): Node | undefined {
-            return isImportMeta(node) ? node : forEachChild(node, walkTreeForExternalModuleIndicators);
-        }
-
-        /** Do not use hasModifier inside the parser; it relies on parent pointers. Use this instead. */
-        function hasModifierOfKind(node: Node, kind: SyntaxKind) {
-            return some(node.modifiers, m => m.kind === kind);
-        }
-
-        function isImportMeta(node: Node): boolean {
-            return isMetaProperty(node) && node.keywordToken === SyntaxKind.ImportKeyword && node.name.escapedText === "meta";
-        }
-
         const enum ParsingContext {
             SourceElements,            // Elements in source file
             BlockStatements,           // Statements in block
@@ -7652,7 +7695,7 @@ namespace ts {
                 currentToken = scanner.scan();
                 const jsDocTypeExpression = parseJSDocTypeExpression();
 
-                const sourceFile = createSourceFile("file.js", ScriptTarget.Latest, ScriptKind.JS, /*isDeclarationFile*/ false, [], factory.createToken(SyntaxKind.EndOfFileToken), NodeFlags.None);
+                const sourceFile = createSourceFile("file.js", ScriptTarget.Latest, ScriptKind.JS, /*isDeclarationFile*/ false, [], factory.createToken(SyntaxKind.EndOfFileToken), NodeFlags.None, noop);
                 const diagnostics = attachFileToDiagnostics(parseDiagnostics, sourceFile);
                 if (jsDocDiagnostics) {
                     sourceFile.jsDocDiagnostics = attachFileToDiagnostics(jsDocDiagnostics, sourceFile);
@@ -8698,7 +8741,7 @@ namespace ts {
             if (sourceFile.statements.length === 0) {
                 // If we don't have any statements in the current source file, then there's no real
                 // way to incrementally parse.  So just do a full parse instead.
-                return Parser.parseSourceFile(sourceFile.fileName, newText, sourceFile.languageVersion, /*syntaxCursor*/ undefined, /*setParentNodes*/ true, sourceFile.scriptKind);
+                return Parser.parseSourceFile(sourceFile.fileName, newText, sourceFile.languageVersion, /*syntaxCursor*/ undefined, /*setParentNodes*/ true, sourceFile.scriptKind, sourceFile.setExternalModuleIndicator);
             }
 
             // Make sure we're not trying to incrementally update a source file more than once.  Once
@@ -8762,7 +8805,7 @@ namespace ts {
             // inconsistent tree.  Setting the parents on the new tree should be very fast.  We
             // will immediately bail out of walking any subtrees when we can see that their parents
             // are already correct.
-            const result = Parser.parseSourceFile(sourceFile.fileName, newText, sourceFile.languageVersion, syntaxCursor, /*setParentNodes*/ true, sourceFile.scriptKind);
+            const result = Parser.parseSourceFile(sourceFile.fileName, newText, sourceFile.languageVersion, syntaxCursor, /*setParentNodes*/ true, sourceFile.scriptKind, sourceFile.setExternalModuleIndicator);
             result.commentDirectives = getNewCommentDirectives(
                 sourceFile.commentDirectives,
                 result.commentDirectives,
diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index 22c38fa986a..31885ec7f12 100644
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -74,7 +74,7 @@ namespace ts {
         const existingDirectories = new Map<string, boolean>();
         const getCanonicalFileName = createGetCanonicalFileName(system.useCaseSensitiveFileNames);
         const computeHash = maybeBind(system, system.createHash) || generateDjb2Hash;
-        function getSourceFile(fileName: string, languageVersion: ScriptTarget, onError?: (message: string) => void): SourceFile | undefined {
+        function getSourceFile(fileName: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void): SourceFile | undefined {
             let text: string | undefined;
             try {
                 performance.mark("beforeIORead");
@@ -88,7 +88,7 @@ namespace ts {
                 }
                 text = "";
             }
-            return text !== undefined ? createSourceFile(fileName, text, languageVersion, setParentNodes) : undefined;
+            return text !== undefined ? createSourceFile(fileName, text, languageVersionOrOptions, setParentNodes) : undefined;
         }
 
         function directoryExists(directoryPath: string): boolean {
@@ -1695,8 +1695,8 @@ namespace ts {
 
             for (const oldSourceFile of oldSourceFiles) {
                 let newSourceFile = host.getSourceFileByPath
-                    ? host.getSourceFileByPath(oldSourceFile.fileName, oldSourceFile.resolvedPath, getEmitScriptTarget(options), /*onError*/ undefined, shouldCreateNewSourceFile)
-                    : host.getSourceFile(oldSourceFile.fileName, getEmitScriptTarget(options), /*onError*/ undefined, shouldCreateNewSourceFile); // TODO: GH#18217
+                    ? host.getSourceFileByPath(oldSourceFile.fileName, oldSourceFile.resolvedPath, getCreateSourceFileOptions(oldSourceFile.fileName, moduleResolutionCache, host, options), /*onError*/ undefined, shouldCreateNewSourceFile)
+                    : host.getSourceFile(oldSourceFile.fileName, getCreateSourceFileOptions(oldSourceFile.fileName, moduleResolutionCache, host, options), /*onError*/ undefined, shouldCreateNewSourceFile); // TODO: GH#18217
 
                 if (!newSourceFile) {
                     return StructureIsReused.Not;
@@ -1731,7 +1731,6 @@ namespace ts {
                 newSourceFile.originalFileName = oldSourceFile.originalFileName;
                 newSourceFile.resolvedPath = oldSourceFile.resolvedPath;
                 newSourceFile.fileName = oldSourceFile.fileName;
-                newSourceFile.impliedNodeFormat = oldSourceFile.impliedNodeFormat;
 
                 const packageName = oldProgram.sourceFileToPackageName.get(oldSourceFile.path);
                 if (packageName !== undefined) {
@@ -2780,6 +2779,18 @@ namespace ts {
             return result;
         }
 
+        function getCreateSourceFileOptions(fileName: string, moduleResolutionCache: ModuleResolutionCache | undefined, host: CompilerHost, options: CompilerOptions) {
+            // It's a _little odd_ that we can't set `impliedNodeFormat` until the program step - but it's the first and only time we have a resolution cache
+            // and a freshly made source file node on hand at the same time, and we need both to set the field. Persisting the resolution cache all the way
+            // to the check and emit steps would be bad - so we much prefer detecting and storing the format information on the source file node upfront.
+            const impliedNodeFormat = getImpliedNodeFormatForFile(toPath(fileName), moduleResolutionCache?.getPackageJsonInfoCache(), host, options);
+            return {
+                languageVersion: getEmitScriptTarget(options),
+                impliedNodeFormat,
+                setExternalModuleIndicator: getSetExternalModuleIndicator(options)
+            };
+        }
+
         function findSourceFileWorker(fileName: string, isDefaultLib: boolean, ignoreNoDefaultLib: boolean, reason: FileIncludeReason, packageId: PackageId | undefined): SourceFile | undefined {
             const path = toPath(fileName);
             if (useSourceOfProjectReferenceRedirect) {
@@ -2872,7 +2883,7 @@ namespace ts {
             // We haven't looked for this file, do so now and cache result
             const file = host.getSourceFile(
                 fileName,
-                getEmitScriptTarget(options),
+                getCreateSourceFileOptions(fileName, moduleResolutionCache, host, options),
                 hostErrorMessage => addFilePreprocessingFileExplainingDiagnostic(/*file*/ undefined, reason, Diagnostics.Cannot_read_file_0_Colon_1, [fileName, hostErrorMessage]),
                 shouldCreateNewSourceFile
             );
@@ -2905,10 +2916,6 @@ namespace ts {
                 file.path = path;
                 file.resolvedPath = toPath(fileName);
                 file.originalFileName = originalFileName;
-                // It's a _little odd_ that we can't set `impliedNodeFormat` until the program step - but it's the first and only time we have a resolution cache
-                // and a freshly made source file node on hand at the same time, and we need both to set the field. Persisting the resolution cache all the way
-                // to the check and emit steps would be bad - so we much prefer detecting and storing the format information on the source file node upfront.
-                file.impliedNodeFormat = getImpliedNodeFormatForFile(file.resolvedPath, moduleResolutionCache?.getPackageJsonInfoCache(), host, options);
                 addFileIncludeReason(file, reason);
 
                 if (host.useCaseSensitiveFileNames()) {
@@ -3501,7 +3508,7 @@ namespace ts {
             }
             else if (firstNonAmbientExternalModuleSourceFile && languageVersion < ScriptTarget.ES2015 && options.module === ModuleKind.None) {
                 // We cannot use createDiagnosticFromNode because nodes do not have parents yet
-                const span = getErrorSpanForNode(firstNonAmbientExternalModuleSourceFile, firstNonAmbientExternalModuleSourceFile.externalModuleIndicator!);
+                const span = getErrorSpanForNode(firstNonAmbientExternalModuleSourceFile, typeof firstNonAmbientExternalModuleSourceFile.externalModuleIndicator === "boolean" ? firstNonAmbientExternalModuleSourceFile : firstNonAmbientExternalModuleSourceFile.externalModuleIndicator!);
                 programDiagnostics.add(createFileDiagnostic(firstNonAmbientExternalModuleSourceFile, span.start, span.length, Diagnostics.Cannot_use_imports_exports_or_module_augmentations_when_module_is_none));
             }
 
@@ -3511,7 +3518,7 @@ namespace ts {
                     createDiagnosticForOptionName(Diagnostics.Only_amd_and_system_modules_are_supported_alongside_0, options.out ? "out" : "outFile", "module");
                 }
                 else if (options.module === undefined && firstNonAmbientExternalModuleSourceFile) {
-                    const span = getErrorSpanForNode(firstNonAmbientExternalModuleSourceFile, firstNonAmbientExternalModuleSourceFile.externalModuleIndicator!);
+                    const span = getErrorSpanForNode(firstNonAmbientExternalModuleSourceFile, typeof firstNonAmbientExternalModuleSourceFile.externalModuleIndicator === "boolean" ? firstNonAmbientExternalModuleSourceFile : firstNonAmbientExternalModuleSourceFile.externalModuleIndicator!);
                     programDiagnostics.add(createFileDiagnostic(firstNonAmbientExternalModuleSourceFile, span.start, span.length, Diagnostics.Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system, options.out ? "out" : "outFile"));
                 }
             }
diff --git a/src/compiler/resolutionCache.ts b/src/compiler/resolutionCache.ts
index c42d99c33c4..d6127fdc1c4 100644
--- a/src/compiler/resolutionCache.ts
+++ b/src/compiler/resolutionCache.ts
@@ -49,7 +49,7 @@ namespace ts {
     interface CachedResolvedTypeReferenceDirectiveWithFailedLookupLocations extends ResolvedTypeReferenceDirectiveWithFailedLookupLocations, ResolutionWithFailedLookupLocations {
     }
 
-    export interface ResolutionCacheHost extends ModuleResolutionHost {
+    export interface ResolutionCacheHost extends MinimalResolutionCacheHost {
         toPath(fileName: string): Path;
         getCanonicalFileName: GetCanonicalFileName;
         getCompilationSettings(): CompilerOptions;
@@ -65,7 +65,6 @@ namespace ts {
         writeLog(s: string): void;
         getCurrentProgram(): Program | undefined;
         fileIsOpen(filePath: Path): boolean;
-        getCompilerHost?(): CompilerHost | undefined;
         onDiscoveredSymlink?(): void;
     }
 
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 53bb25c4597..3fee2e6eac4 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -3622,7 +3622,13 @@ namespace ts {
          * This is intended to be the first top-level import/export,
          * but could be arbitrarily nested (e.g. `import.meta`).
          */
-        /* @internal */ externalModuleIndicator?: Node;
+        /* @internal */ externalModuleIndicator?: Node | true;
+        /**
+         * The callback used to set the external module indicator - this is saved to
+         * be later reused during incremental reparsing, which otherwise lacks the information
+         * to set this field
+         */
+        /* @internal */ setExternalModuleIndicator?: (file: SourceFile) => void;
         // The first node that causes this file to be a CommonJS module
         /* @internal */ commonJsModuleIndicator?: Node;
         // JS identifier-declarations that are intended to merge with globals
@@ -6029,6 +6035,21 @@ namespace ts {
         NodeNext = 99, // Not simply `Node12` so that compiled code linked against TS can use the `Next` value reliably (same as with `ModuleKind`)
     }
 
+    export enum ModuleDetectionKind {
+        /**
+         * Files with imports, exports and/or import.meta are considered modules
+         */
+        Legacy = 1,
+        /**
+         * Legacy, but also files with jsx under react-jsx or react-jsxdev and esm mode files under moduleResolution: node12+
+         */
+        Auto = 2,
+        /**
+         * Consider all non-declaration files modules, regardless of present syntax
+         */
+        Force = 3,
+    }
+
     export interface PluginImport {
         name: string;
     }
@@ -6124,6 +6145,7 @@ namespace ts {
         maxNodeModuleJsDepth?: number;
         module?: ModuleKind;
         moduleResolution?: ModuleResolutionKind;
+        moduleDetection?: ModuleDetectionKind;
         newLine?: NewLineKind;
         noEmit?: boolean;
         /*@internal*/noEmitForJsFiles?: boolean;
@@ -6588,6 +6610,14 @@ namespace ts {
         useCaseSensitiveFileNames?: boolean | (() => boolean);
     }
 
+    /**
+     * Used by services to specify the minimum host area required to set up source files under any compilation settings
+     */
+    export interface MinimalResolutionCacheHost extends ModuleResolutionHost {
+        getCompilationSettings(): CompilerOptions;
+        getCompilerHost?(): CompilerHost | undefined;
+    }
+
     /**
      * Represents the result of module resolution.
      * Module resolution will pick up tsx/jsx/js files even if '--jsx' and '--allowJs' are turned off.
@@ -6690,8 +6720,8 @@ namespace ts {
     export type HasChangedAutomaticTypeDirectiveNames = () => boolean;
 
     export interface CompilerHost extends ModuleResolutionHost {
-        getSourceFile(fileName: string, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
-        getSourceFileByPath?(fileName: string, path: Path, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
+        getSourceFile(fileName: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
+        getSourceFileByPath?(fileName: string, path: Path, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
         getCancellationToken?(): CancellationToken;
         getDefaultLibFileName(options: CompilerOptions): string;
         getDefaultLibLocation?(): string;
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index 76758e2d46c..3366b214d09 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -6216,6 +6216,63 @@ namespace ts {
         return scriptKind === ScriptKind.TSX || scriptKind === ScriptKind.JSX || scriptKind === ScriptKind.JS || scriptKind === ScriptKind.JSON ? LanguageVariant.JSX : LanguageVariant.Standard;
     }
 
+    /**
+     * This is a somewhat unavoidable full tree walk to locate a JSX tag - `import.meta` requires the same,
+     * but we avoid that walk (or parts of it) if at all possible using the `PossiblyContainsImportMeta` node flag.
+     * Unfortunately, there's no `NodeFlag` space to do the same for JSX.
+     */
+    function walkTreeForJSXTags(node: Node): Node | undefined {
+        if (!(node.transformFlags & TransformFlags.ContainsJsx)) return undefined;
+        return isJsxOpeningLikeElement(node) || isJsxFragment(node) ? node : forEachChild(node, walkTreeForJSXTags);
+    }
+
+    function isFileModuleFromUsingJSXTag(file: SourceFile): Node | undefined {
+        // Excludes declaration files - they still require an explicit `export {}` or the like
+        // for back compat purposes. (not that declaration files should contain JSX tags!)
+        return !file.isDeclarationFile ? walkTreeForJSXTags(file) : undefined;
+    }
+
+    /**
+     * Note that this requires file.impliedNodeFormat be set already; meaning it must be set very early on
+     * in SourceFile construction.
+     */
+    function isFileForcedToBeModuleByFormat(file: SourceFile): true | undefined {
+        // Excludes declaration files - they still require an explicit `export {}` or the like
+        // for back compat purposes.
+        return file.impliedNodeFormat === ModuleKind.ESNext && !file.isDeclarationFile ? true : undefined;
+    }
+
+    export function getSetExternalModuleIndicator(options: CompilerOptions): (file: SourceFile) => void {
+        // TODO: Should this callback be cached?
+        switch (getEmitModuleDetectionKind(options)) {
+            case ModuleDetectionKind.Force:
+                // All non-declaration files are modules, declaration files still do the usual isFileProbablyExternalModule
+                return (file: SourceFile) => {
+                    file.externalModuleIndicator = !file.isDeclarationFile || isFileProbablyExternalModule(file);
+                };
+            case ModuleDetectionKind.Legacy:
+                // Files are modules if they have imports, exports, or import.meta
+                return (file: SourceFile) => {
+                    file.externalModuleIndicator = isFileProbablyExternalModule(file);
+                };
+            case ModuleDetectionKind.Auto:
+                // If module is nodenext or node12, all esm format files are modules
+                // If jsx is react-jsx or react-jsxdev then jsx tags force module-ness
+                // otherwise, the presence of import or export statments (or import.meta) implies module-ness
+                const checks: ((file: SourceFile) => Node | true | undefined)[] = [isFileProbablyExternalModule];
+                if (options.jsx === JsxEmit.ReactJSX || options.jsx === JsxEmit.ReactJSXDev) {
+                    checks.push(isFileModuleFromUsingJSXTag);
+                }
+                const moduleKind = getEmitModuleKind(options);
+                if (moduleKind === ModuleKind.Node12 || moduleKind === ModuleKind.NodeNext) {
+                    checks.push(isFileForcedToBeModuleByFormat);
+                }
+                const combined = or(...checks);
+                const callback = (file: SourceFile) => void (file.externalModuleIndicator = combined(file));
+                return callback;
+        }
+    }
+
     export function getEmitScriptTarget(compilerOptions: {module?: CompilerOptions["module"], target?: CompilerOptions["target"]}) {
         return compilerOptions.target ||
             (compilerOptions.module === ModuleKind.Node12 && ScriptTarget.ES2020) ||
@@ -6250,6 +6307,10 @@ namespace ts {
         return moduleResolution;
     }
 
+    export function getEmitModuleDetectionKind(options: CompilerOptions) {
+        return options.moduleDetection || ModuleDetectionKind.Auto;
+    }
+
     export function hasJsonModuleEmitEnabled(options: CompilerOptions) {
         switch (getEmitModuleKind(options)) {
             case ModuleKind.CommonJS:
diff --git a/src/compiler/watch.ts b/src/compiler/watch.ts
index 5e8c950da4e..b2f7a0a3bc5 100644
--- a/src/compiler/watch.ts
+++ b/src/compiler/watch.ts
@@ -539,7 +539,7 @@ namespace ts {
         const useCaseSensitiveFileNames = host.useCaseSensitiveFileNames();
         const hostGetNewLine = memoize(() => host.getNewLine());
         return {
-            getSourceFile: (fileName, languageVersion, onError) => {
+            getSourceFile: (fileName, languageVersionOrOptions, onError) => {
                 let text: string | undefined;
                 try {
                     performance.mark("beforeIORead");
@@ -554,7 +554,7 @@ namespace ts {
                     text = "";
                 }
 
-                return text !== undefined ? createSourceFile(fileName, text, languageVersion) : undefined;
+                return text !== undefined ? createSourceFile(fileName, text, languageVersionOrOptions) : undefined;
             },
             getDefaultLibLocation: maybeBind(host, host.getDefaultLibLocation),
             getDefaultLibFileName: options => host.getDefaultLibFileName(options),
diff --git a/src/compiler/watchPublic.ts b/src/compiler/watchPublic.ts
index 1f6ec39df4e..095c0f69a10 100644
--- a/src/compiler/watchPublic.ts
+++ b/src/compiler/watchPublic.ts
@@ -532,7 +532,7 @@ namespace ts {
             return directoryStructureHost.fileExists(fileName);
         }
 
-        function getVersionedSourceFileByPath(fileName: string, path: Path, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined {
+        function getVersionedSourceFileByPath(fileName: string, path: Path, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined {
             const hostSourceFile = sourceFilesCache.get(path);
             // No source file on the host
             if (isFileMissingOnHost(hostSourceFile)) {
@@ -541,7 +541,7 @@ namespace ts {
 
             // Create new source file if requested or the versions dont match
             if (hostSourceFile === undefined || shouldCreateNewSourceFile || isFilePresenceUnknownOnHost(hostSourceFile)) {
-                const sourceFile = getNewSourceFile(fileName, languageVersion, onError);
+                const sourceFile = getNewSourceFile(fileName, languageVersionOrOptions, onError);
                 if (hostSourceFile) {
                     if (sourceFile) {
                         // Set the source file and create file watcher now that file was present on the disk
diff --git a/src/harness/fourslashImpl.ts b/src/harness/fourslashImpl.ts
index 47ed0e4a1ae..b8513c37442 100644
--- a/src/harness/fourslashImpl.ts
+++ b/src/harness/fourslashImpl.ts
@@ -2293,8 +2293,18 @@ namespace FourSlash {
             // Check syntactic structure
             const content = this.getFileContent(this.activeFile.fileName);
 
+            const options: ts.CreateSourceFileOptions = {
+                languageVersion: ts.ScriptTarget.Latest,
+                impliedNodeFormat: ts.getImpliedNodeFormatForFile(
+                    ts.toPath(this.activeFile.fileName, this.languageServiceAdapterHost.sys.getCurrentDirectory(), ts.hostGetCanonicalFileName(this.languageServiceAdapterHost)),
+                    /*cache*/ undefined,
+                    this.languageServiceAdapterHost,
+                    this.languageService.getProgram()?.getCompilerOptions() || {}
+                ),
+                setExternalModuleIndicator: ts.getSetExternalModuleIndicator(this.languageService.getProgram()?.getCompilerOptions() || {})
+            };
             const referenceSourceFile = ts.createLanguageServiceSourceFile(
-                this.activeFile.fileName, createScriptSnapShot(content), ts.ScriptTarget.Latest, /*version:*/ "0", /*setNodeParents:*/ false);
+                this.activeFile.fileName, createScriptSnapShot(content), options, /*version:*/ "0", /*setNodeParents:*/ false);
             const referenceSyntaxDiagnostics = referenceSourceFile.parseDiagnostics;
 
             Utils.assertDiagnosticsEquals(incrementalSyntaxDiagnostics, referenceSyntaxDiagnostics);
diff --git a/src/harness/harnessLanguageService.ts b/src/harness/harnessLanguageService.ts
index dc41722f26c..be17bbdef0e 100644
--- a/src/harness/harnessLanguageService.ts
+++ b/src/harness/harnessLanguageService.ts
@@ -163,6 +163,24 @@ namespace Harness.LanguageService {
             }
         }
 
+        public fileExists(path: string): boolean {
+            try {
+                return this.vfs.existsSync(path);
+            }
+            catch {
+                return false;
+            }
+        }
+
+        public readFile(path: string): string | undefined {
+            try {
+                return this.vfs.readFileSync(path).toString();
+            }
+            catch {
+                return undefined;
+            }
+        }
+
         public directoryExists(path: string) {
             return this.vfs.statSync(path).isDirectory();
         }
diff --git a/src/server/project.ts b/src/server/project.ts
index b9ec87f4115..91bc1e639a3 100644
--- a/src/server/project.ts
+++ b/src/server/project.ts
@@ -1678,6 +1678,11 @@ namespace ts.server {
             return packageJsons;
         }
 
+        /* @internal */
+        getPackageJsonCache() {
+            return this.projectService.packageJsonCache;
+        }
+
         /*@internal*/
         getCachedExportInfoMap() {
             return this.exportMapCache ||= createCacheableExportInfoMap(this);
diff --git a/src/services/documentRegistry.ts b/src/services/documentRegistry.ts
index ff440a84543..7446f895db2 100644
--- a/src/services/documentRegistry.ts
+++ b/src/services/documentRegistry.ts
@@ -21,9 +21,12 @@ namespace ts {
          * the SourceFile if was not found in the registry.
          *
          * @param fileName The name of the file requested
-         * @param compilationSettings Some compilation settings like target affects the
+         * @param compilationSettingsOrHost Some compilation settings like target affects the
          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
-         * multiple copies of the same file for different compilation settings.
+         * multiple copies of the same file for different compilation settings. A minimal
+         * resolution cache is needed to fully define a source file's shape when
+         * the compilation settings include `module: node12`+, so providing a cache host
+         * object should be preferred. A common host is a language service `ConfiguredProject`.
          * @param scriptSnapshot Text of the file. Only used if the file was not found
          * in the registry and a new one was created.
          * @param version Current version of the file. Only used if the file was not found
@@ -31,7 +34,7 @@ namespace ts {
          */
         acquireDocument(
             fileName: string,
-            compilationSettings: CompilerOptions,
+            compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost,
             scriptSnapshot: IScriptSnapshot,
             version: string,
             scriptKind?: ScriptKind): SourceFile;
@@ -39,7 +42,7 @@ namespace ts {
         acquireDocumentWithKey(
             fileName: string,
             path: Path,
-            compilationSettings: CompilerOptions,
+            compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost,
             key: DocumentRegistryBucketKey,
             scriptSnapshot: IScriptSnapshot,
             version: string,
@@ -51,15 +54,18 @@ namespace ts {
          * to get an updated SourceFile.
          *
          * @param fileName The name of the file requested
-         * @param compilationSettings Some compilation settings like target affects the
+         * @param compilationSettingsOrHost Some compilation settings like target affects the
          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
-         * multiple copies of the same file for different compilation settings.
+         * multiple copies of the same file for different compilation settings. A minimal
+         * resolution cache is needed to fully define a source file's shape when
+         * the compilation settings include `module: node12`+, so providing a cache host
+         * object should be preferred. A common host is a language service `ConfiguredProject`.
          * @param scriptSnapshot Text of the file.
          * @param version Current version of the file.
          */
         updateDocument(
             fileName: string,
-            compilationSettings: CompilerOptions,
+            compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost,
             scriptSnapshot: IScriptSnapshot,
             version: string,
             scriptKind?: ScriptKind): SourceFile;
@@ -67,7 +73,7 @@ namespace ts {
         updateDocumentWithKey(
             fileName: string,
             path: Path,
-            compilationSettings: CompilerOptions,
+            compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost,
             key: DocumentRegistryBucketKey,
             scriptSnapshot: IScriptSnapshot,
             version: string,
@@ -165,24 +171,31 @@ namespace ts {
             return JSON.stringify(bucketInfoArray, undefined, 2);
         }
 
-        function acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
+        function getCompilationSettings(settingsOrHost: CompilerOptions | MinimalResolutionCacheHost) {
+            if (typeof settingsOrHost.getCompilationSettings === "function") {
+                return (settingsOrHost as MinimalResolutionCacheHost).getCompilationSettings();
+            }
+            return settingsOrHost as CompilerOptions;
+        }
+
+        function acquireDocument(fileName: string, compilationSettings: CompilerOptions | MinimalResolutionCacheHost, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
             const path = toPath(fileName, currentDirectory, getCanonicalFileName);
-            const key = getKeyForCompilationSettings(compilationSettings);
+            const key = getKeyForCompilationSettings(getCompilationSettings(compilationSettings));
             return acquireDocumentWithKey(fileName, path, compilationSettings, key, scriptSnapshot, version, scriptKind);
         }
 
-        function acquireDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
+        function acquireDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions | MinimalResolutionCacheHost, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
             return acquireOrUpdateDocument(fileName, path, compilationSettings, key, scriptSnapshot, version, /*acquiring*/ true, scriptKind);
         }
 
-        function updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
+        function updateDocument(fileName: string, compilationSettings: CompilerOptions | MinimalResolutionCacheHost, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
             const path = toPath(fileName, currentDirectory, getCanonicalFileName);
-            const key = getKeyForCompilationSettings(compilationSettings);
+            const key = getKeyForCompilationSettings(getCompilationSettings(compilationSettings));
             return updateDocumentWithKey(fileName, path, compilationSettings, key, scriptSnapshot, version, scriptKind);
         }
 
-        function updateDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
-            return acquireOrUpdateDocument(fileName, path, compilationSettings, key, scriptSnapshot, version, /*acquiring*/ false, scriptKind);
+        function updateDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions | MinimalResolutionCacheHost, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile {
+            return acquireOrUpdateDocument(fileName, path, getCompilationSettings(compilationSettings), key, scriptSnapshot, version, /*acquiring*/ false, scriptKind);
         }
 
         function getDocumentRegistryEntry(bucketEntry: BucketEntry, scriptKind: ScriptKind | undefined) {
@@ -194,14 +207,21 @@ namespace ts {
         function acquireOrUpdateDocument(
             fileName: string,
             path: Path,
-            compilationSettings: CompilerOptions,
+            compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost,
             key: DocumentRegistryBucketKey,
             scriptSnapshot: IScriptSnapshot,
             version: string,
             acquiring: boolean,
             scriptKind?: ScriptKind): SourceFile {
             scriptKind = ensureScriptKind(fileName, scriptKind);
+            const compilationSettings = getCompilationSettings(compilationSettingsOrHost);
+            const host: MinimalResolutionCacheHost | undefined = compilationSettingsOrHost === compilationSettings ? undefined : compilationSettingsOrHost as MinimalResolutionCacheHost;
             const scriptTarget = scriptKind === ScriptKind.JSON ? ScriptTarget.JSON : getEmitScriptTarget(compilationSettings);
+            const sourceFileOptions: CreateSourceFileOptions = {
+                languageVersion: scriptTarget,
+                impliedNodeFormat: host && getImpliedNodeFormatForFile(path, host.getCompilerHost?.()?.getModuleResolutionCache?.()?.getPackageJsonInfoCache(), host, compilationSettings),
+                setExternalModuleIndicator: getSetExternalModuleIndicator(compilationSettings)
+            };
 
             const oldBucketCount = buckets.size;
             const bucket = getOrUpdate(buckets, key, () => new Map());
@@ -239,7 +259,7 @@ namespace ts {
 
             if (!entry) {
                 // Have never seen this file with these settings.  Create a new source file for it.
-                const sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, scriptTarget, version, /*setNodeParents*/ false, scriptKind);
+                const sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, sourceFileOptions, version, /*setNodeParents*/ false, scriptKind);
                 if (externalCache) {
                     externalCache.setDocument(key, path, sourceFile);
                 }
diff --git a/src/services/refactors/moveToNewFile.ts b/src/services/refactors/moveToNewFile.ts
index 6e5d9c891e7..2e96d5aa95b 100644
--- a/src/services/refactors/moveToNewFile.ts
+++ b/src/services/refactors/moveToNewFile.ts
@@ -473,7 +473,7 @@ namespace ts.refactor {
         let newModuleName = moduleName;
         for (let i = 1; ; i++) {
             const name = combinePaths(inDirectory, newModuleName + extension);
-            if (!host.fileExists!(name)) return newModuleName; // TODO: GH#18217
+            if (!host.fileExists(name)) return newModuleName;
             newModuleName = `${moduleName}.${i}`;
         }
     }
diff --git a/src/services/services.ts b/src/services/services.ts
index 6d144565dcc..503482d63c7 100644
--- a/src/services/services.ts
+++ b/src/services/services.ts
@@ -1085,7 +1085,17 @@ namespace ts {
 
             if (this.currentFileName !== fileName) {
                 // This is a new file, just parse it
-                sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, ScriptTarget.Latest, version, /*setNodeParents*/ true, scriptKind);
+                const options: CreateSourceFileOptions = {
+                    languageVersion: ScriptTarget.Latest,
+                    impliedNodeFormat: getImpliedNodeFormatForFile(
+                        toPath(fileName, this.host.getCurrentDirectory(), this.host.getCompilerHost?.()?.getCanonicalFileName || hostGetCanonicalFileName(this.host)),
+                        this.host.getCompilerHost?.()?.getModuleResolutionCache?.()?.getPackageJsonInfoCache(),
+                        this.host,
+                        this.host.getCompilationSettings()
+                    ),
+                    setExternalModuleIndicator: getSetExternalModuleIndicator(this.host.getCompilationSettings())
+                };
+                sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, options, version, /*setNodeParents*/ true, scriptKind);
             }
             else if (this.currentFileVersion !== version) {
                 // This is the same file, just a newer version. Incrementally parse the file.
@@ -1110,8 +1120,8 @@ namespace ts {
         sourceFile.scriptSnapshot = scriptSnapshot;
     }
 
-    export function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTarget: ScriptTarget, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile {
-        const sourceFile = createSourceFile(fileName, getSnapshotText(scriptSnapshot), scriptTarget, setNodeParents, scriptKind);
+    export function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTargetOrOptions: ScriptTarget | CreateSourceFileOptions, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile {
+        const sourceFile = createSourceFile(fileName, getSnapshotText(scriptSnapshot), scriptTargetOrOptions, setNodeParents, scriptKind);
         setSourceFileFields(sourceFile, scriptSnapshot, version);
         return sourceFile;
     }
@@ -1167,8 +1177,13 @@ namespace ts {
             }
         }
 
+        const options: CreateSourceFileOptions = {
+            languageVersion: sourceFile.languageVersion,
+            impliedNodeFormat: sourceFile.impliedNodeFormat,
+            setExternalModuleIndicator: sourceFile.setExternalModuleIndicator,
+        };
         // Otherwise, just create a new source file.
-        return createLanguageServiceSourceFile(sourceFile.fileName, scriptSnapshot, sourceFile.languageVersion, version, /*setNodeParents*/ true, sourceFile.scriptKind);
+        return createLanguageServiceSourceFile(sourceFile.fileName, scriptSnapshot, options, version, /*setNodeParents*/ true, sourceFile.scriptKind);
     }
 
     const NoopCancellationToken: CancellationToken = {
@@ -1551,7 +1566,7 @@ namespace ts {
                         // file's script kind, i.e. in one project some file is treated as ".ts"
                         // and in another as ".js"
                         if (hostFileInformation.scriptKind === oldSourceFile.scriptKind) {
-                            return documentRegistry.updateDocumentWithKey(fileName, path, newSettings, documentRegistryBucketKey, hostFileInformation.scriptSnapshot, hostFileInformation.version, hostFileInformation.scriptKind);
+                            return documentRegistry.updateDocumentWithKey(fileName, path, host, documentRegistryBucketKey, hostFileInformation.scriptSnapshot, hostFileInformation.version, hostFileInformation.scriptKind);
                         }
                         else {
                             // Release old source file and fall through to aquire new file with new script kind
@@ -1563,7 +1578,7 @@ namespace ts {
                 }
 
                 // Could not find this file in the old program, create a new SourceFile for it.
-                return documentRegistry.acquireDocumentWithKey(fileName, path, newSettings, documentRegistryBucketKey, hostFileInformation.scriptSnapshot, hostFileInformation.version, hostFileInformation.scriptKind);
+                return documentRegistry.acquireDocumentWithKey(fileName, path, host, documentRegistryBucketKey, hostFileInformation.scriptSnapshot, hostFileInformation.version, hostFileInformation.scriptKind);
             }
         }
 
diff --git a/src/services/suggestionDiagnostics.ts b/src/services/suggestionDiagnostics.ts
index 314d4d485b8..7be5d210b36 100644
--- a/src/services/suggestionDiagnostics.ts
+++ b/src/services/suggestionDiagnostics.ts
@@ -27,7 +27,7 @@ namespace ts {
                 if (!name) continue;
                 const module = getResolvedModule(sourceFile, moduleSpecifier.text, getModeForUsageLocation(sourceFile, moduleSpecifier));
                 const resolvedFile = module && program.getSourceFile(module.resolvedFileName);
-                if (resolvedFile && resolvedFile.externalModuleIndicator && isExportAssignment(resolvedFile.externalModuleIndicator) && resolvedFile.externalModuleIndicator.isExportEquals) {
+                if (resolvedFile && resolvedFile.externalModuleIndicator && resolvedFile.externalModuleIndicator !== true && isExportAssignment(resolvedFile.externalModuleIndicator) && resolvedFile.externalModuleIndicator.isExportEquals) {
                     diags.push(createDiagnosticForNode(name, Diagnostics.Import_may_be_converted_to_a_default_import));
                 }
             }
diff --git a/src/services/transpile.ts b/src/services/transpile.ts
index 5b73b91bd7f..b2d8951e43b 100644
--- a/src/services/transpile.ts
+++ b/src/services/transpile.ts
@@ -46,23 +46,7 @@ namespace ts {
         // Filename can be non-ts file.
         options.allowNonTsExtensions = true;
 
-        // if jsx is specified then treat file as .tsx
-        const inputFileName = transpileOptions.fileName || (transpileOptions.compilerOptions && transpileOptions.compilerOptions.jsx ? "module.tsx" : "module.ts");
-        const sourceFile = createSourceFile(inputFileName, input, getEmitScriptTarget(options));
-        if (transpileOptions.moduleName) {
-            sourceFile.moduleName = transpileOptions.moduleName;
-        }
-
-        if (transpileOptions.renamedDependencies) {
-            sourceFile.renamedDependencies = new Map(getEntries(transpileOptions.renamedDependencies));
-        }
-
         const newLine = getNewLineCharacter(options);
-
-        // Output
-        let outputText: string | undefined;
-        let sourceMapText: string | undefined;
-
         // Create a compilerHost object to allow the compiler to read and write files
         const compilerHost: CompilerHost = {
             getSourceFile: (fileName) => fileName === normalizePath(inputFileName) ? sourceFile : undefined,
@@ -87,6 +71,29 @@ namespace ts {
             getDirectories: () => []
         };
 
+        // if jsx is specified then treat file as .tsx
+        const inputFileName = transpileOptions.fileName || (transpileOptions.compilerOptions && transpileOptions.compilerOptions.jsx ? "module.tsx" : "module.ts");
+        const sourceFile = createSourceFile(
+            inputFileName,
+            input,
+            {
+                languageVersion: getEmitScriptTarget(options),
+                impliedNodeFormat: getImpliedNodeFormatForFile(toPath(inputFileName, "", compilerHost.getCanonicalFileName), /*cache*/ undefined, compilerHost, options),
+                setExternalModuleIndicator: getSetExternalModuleIndicator(options)
+            }
+        );
+        if (transpileOptions.moduleName) {
+            sourceFile.moduleName = transpileOptions.moduleName;
+        }
+
+        if (transpileOptions.renamedDependencies) {
+            sourceFile.renamedDependencies = new Map(getEntries(transpileOptions.renamedDependencies));
+        }
+
+        // Output
+        let outputText: string | undefined;
+        let sourceMapText: string | undefined;
+
         const program = createProgram([inputFileName], options, compilerHost);
 
         if (transpileOptions.reportDiagnostics) {
diff --git a/src/services/types.ts b/src/services/types.ts
index 66730a23a53..a32fa6599fa 100644
--- a/src/services/types.ts
+++ b/src/services/types.ts
@@ -240,7 +240,7 @@ namespace ts {
     //
     // Public interface of the host of a language service instance.
     //
-    export interface LanguageServiceHost extends GetEffectiveTypeRootsHost {
+    export interface LanguageServiceHost extends GetEffectiveTypeRootsHost, MinimalResolutionCacheHost {
         getCompilationSettings(): CompilerOptions;
         getNewLine?(): string;
         getProjectVersion?(): string;
@@ -263,9 +263,14 @@ namespace ts {
          * Without these methods, only completions for ambient modules will be provided.
          */
         readDirectory?(path: string, extensions?: readonly string[], exclude?: readonly string[], include?: readonly string[], depth?: number): string[];
-        readFile?(path: string, encoding?: string): string | undefined;
         realpath?(path: string): string;
-        fileExists?(path: string): boolean;
+
+        /*
+         * Unlike `realpath and `readDirectory`, `readFile` and `fileExists` are now _required_
+         * to properly acquire and setup source files under module: node12+ modes.
+         */
+        readFile(path: string, encoding?: string): string | undefined;
+        fileExists(path: string): boolean;
 
         /*
          * LS host can optionally implement these methods to support automatic updating when new type libraries are installed
diff --git a/src/services/utilities.ts b/src/services/utilities.ts
index b3fcce81482..88836f59c34 100644
--- a/src/services/utilities.ts
+++ b/src/services/utilities.ts
@@ -2941,7 +2941,7 @@ namespace ts {
         const packageJsons: PackageJsonInfo[] = [];
         forEachAncestorDirectory(getDirectoryPath(fileName), ancestor => {
             const packageJsonFileName = combinePaths(ancestor, "package.json");
-            if (host.fileExists!(packageJsonFileName)) {
+            if (host.fileExists(packageJsonFileName)) {
                 const info = createPackageJsonInfo(packageJsonFileName, host);
                 if (info) {
                     packageJsons.push(info);
diff --git a/src/testRunner/compilerRunner.ts b/src/testRunner/compilerRunner.ts
index 166ed164f77..1d320d667cf 100644
--- a/src/testRunner/compilerRunner.ts
+++ b/src/testRunner/compilerRunner.ts
@@ -118,6 +118,7 @@ namespace Harness {
         private static varyBy: readonly string[] = [
             "module",
             "moduleResolution",
+            "moduleDetection",
             "target",
             "jsx",
             "removeComments",
diff --git a/src/testRunner/unittests/services/extract/helpers.ts b/src/testRunner/unittests/services/extract/helpers.ts
index b0fa383c96e..660c903bd2b 100644
--- a/src/testRunner/unittests/services/extract/helpers.ts
+++ b/src/testRunner/unittests/services/extract/helpers.ts
@@ -72,6 +72,8 @@ namespace ts {
         getScriptSnapshot: notImplemented,
         getDefaultLibFileName: notImplemented,
         getCurrentDirectory: notImplemented,
+        readFile: notImplemented,
+        fileExists: notImplemented
     };
 
     export function testExtractSymbol(caption: string, text: string, baselineFolder: string, description: DiagnosticMessage, includeLib?: boolean) {
diff --git a/src/testRunner/unittests/services/hostNewLineSupport.ts b/src/testRunner/unittests/services/hostNewLineSupport.ts
index 057cb60602a..762b8e3ddc1 100644
--- a/src/testRunner/unittests/services/hostNewLineSupport.ts
+++ b/src/testRunner/unittests/services/hostNewLineSupport.ts
@@ -15,6 +15,12 @@ namespace ts {
                 getScriptSnapshot: name => snapFor(name),
                 getDefaultLibFileName: () => "lib.d.ts",
                 getCurrentDirectory: () => "",
+                readFile: name => {
+                    const snap = snapFor(name);
+                    if (!snap) return undefined;
+                    return snap.getText(0, snap.getLength());
+                },
+                fileExists: name => !!snapFor(name),
             };
             return createLanguageService(lshost);
         }
diff --git a/src/testRunner/unittests/services/languageService.ts b/src/testRunner/unittests/services/languageService.ts
index a1f7e5844b8..c3f5f019541 100644
--- a/src/testRunner/unittests/services/languageService.ts
+++ b/src/testRunner/unittests/services/languageService.ts
@@ -39,6 +39,8 @@ export function Component(x: Config): any;`
                 getDefaultLibFileName(options) {
                     return getDefaultLibFilePath(options);
                 },
+                fileExists: name => !!files[name],
+                readFile: name => files[name]
             });
         }
         // Regression test for GH #18245 - bug in single line comment writer caused a debug assertion when attempting
@@ -94,6 +96,7 @@ export function Component(x: Config): any;`
                     useCaseSensitiveFileNames: returnTrue,
                     getCompilationSettings: getDefaultCompilerOptions,
                     fileExists: path => files.has(path),
+                    readFile: path => files.get(path)?.text,
                     getProjectVersion: !useProjectVersion ? undefined : () => projectVersion,
                     getScriptFileNames: () => ["/project/root.ts"],
                     getScriptVersion: path => files.get(path)?.version || "",
@@ -189,6 +192,7 @@ export function Component(x: Config): any;`
                     useSourceOfProjectReferenceRedirect,
                     getCompilationSettings: () => result.options,
                     fileExists: path => system.fileExists(path),
+                    readFile: path => system.readFile(path),
                     getScriptFileNames: () => result.fileNames,
                     getScriptVersion: path => {
                         const text = system.readFile(path);
diff --git a/tests/baselines/reference/APISample_watcher.js b/tests/baselines/reference/APISample_watcher.js
index 8241222971b..d86eb60e677 100644
--- a/tests/baselines/reference/APISample_watcher.js
+++ b/tests/baselines/reference/APISample_watcher.js
@@ -47,6 +47,8 @@ function watch(rootFileNames: string[], options: ts.CompilerOptions) {
         getCurrentDirectory: () => process.cwd(),
         getCompilationSettings: () => options,
         getDefaultLibFileName: (options) => ts.getDefaultLibFilePath(options),
+        fileExists: fileName => fs.existsSync(fileName),
+        readFile: fileName => fs.readFileSync(fileName),
     };
 
     // Create the language service files
@@ -143,7 +145,9 @@ function watch(rootFileNames, options) {
         },
         getCurrentDirectory: function () { return process.cwd(); },
         getCompilationSettings: function () { return options; },
-        getDefaultLibFileName: function (options) { return ts.getDefaultLibFilePath(options); }
+        getDefaultLibFileName: function (options) { return ts.getDefaultLibFilePath(options); },
+        fileExists: function (fileName) { return fs.existsSync(fileName); },
+        readFile: function (fileName) { return fs.readFileSync(fileName); }
     };
     // Create the language service files
     var services = ts.createLanguageService(servicesHost, ts.createDocumentRegistry());
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index 9bddee3a017..fcb78f56f6c 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -2888,6 +2888,20 @@ declare namespace ts {
         Node12 = 3,
         NodeNext = 99
     }
+    export enum ModuleDetectionKind {
+        /**
+         * Files with imports, exports and/or import.meta are considered modules
+         */
+        Legacy = 1,
+        /**
+         * Legacy, but also files with jsx under react-jsx or react-jsxdev and esm mode files under moduleResolution: node12+
+         */
+        Auto = 2,
+        /**
+         * Consider all non-declaration files modules, regardless of present syntax
+         */
+        Force = 3
+    }
     export interface PluginImport {
         name: string;
     }
@@ -2959,6 +2973,7 @@ declare namespace ts {
         maxNodeModuleJsDepth?: number;
         module?: ModuleKind;
         moduleResolution?: ModuleResolutionKind;
+        moduleDetection?: ModuleDetectionKind;
         newLine?: NewLineKind;
         noEmit?: boolean;
         noEmitHelpers?: boolean;
@@ -3146,6 +3161,13 @@ declare namespace ts {
         getDirectories?(path: string): string[];
         useCaseSensitiveFileNames?: boolean | (() => boolean);
     }
+    /**
+     * Used by services to specify the minimum host area required to set up source files under any compilation settings
+     */
+    export interface MinimalResolutionCacheHost extends ModuleResolutionHost {
+        getCompilationSettings(): CompilerOptions;
+        getCompilerHost?(): CompilerHost | undefined;
+    }
     /**
      * Represents the result of module resolution.
      * Module resolution will pick up tsx/jsx/js files even if '--jsx' and '--allowJs' are turned off.
@@ -3221,8 +3243,8 @@ declare namespace ts {
         readonly failedLookupLocations: string[];
     }
     export interface CompilerHost extends ModuleResolutionHost {
-        getSourceFile(fileName: string, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
-        getSourceFileByPath?(fileName: string, path: Path, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
+        getSourceFile(fileName: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
+        getSourceFileByPath?(fileName: string, path: Path, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
         getCancellationToken?(): CancellationToken;
         getDefaultLibFileName(options: CompilerOptions): string;
         getDefaultLibLocation?(): string;
@@ -4776,7 +4798,22 @@ declare namespace ts {
      * that they appear in the source code. The language service depends on this property to locate nodes by position.
      */
     export function forEachChild<T>(node: Node, cbNode: (node: Node) => T | undefined, cbNodes?: (nodes: NodeArray<Node>) => T | undefined): T | undefined;
-    export function createSourceFile(fileName: string, sourceText: string, languageVersion: ScriptTarget, setParentNodes?: boolean, scriptKind?: ScriptKind): SourceFile;
+    export interface CreateSourceFileOptions {
+        languageVersion: ScriptTarget;
+        /**
+         * Controls the format the file is detected as - this can be derived from only the path
+         * and files on disk, but needs to be done with a module resolution cache in scope to be performant.
+         * This is usually `undefined` for compilations that do not have `moduleResolution` values of `node12` or `nodenext`.
+         */
+        impliedNodeFormat?: ModuleKind.ESNext | ModuleKind.CommonJS;
+        /**
+         * Controls how module-y-ness is set for the given file. Usually the result of calling
+         * `getSetExternalModuleIndicator` on a valid `CompilerOptions` object. If not present, the default
+         * check specified by `isFileProbablyExternalModule` will be used to set the field.
+         */
+        setExternalModuleIndicator?: (file: SourceFile) => void;
+    }
+    export function createSourceFile(fileName: string, sourceText: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, setParentNodes?: boolean, scriptKind?: ScriptKind): SourceFile;
     export function parseIsolatedEntityName(text: string, languageVersion: ScriptTarget): EntityName | undefined;
     /**
      * Parse json text into SyntaxTree and return node and parse errors if any
@@ -5676,7 +5713,7 @@ declare namespace ts {
         set(response: CompletionInfo): void;
         clear(): void;
     }
-    interface LanguageServiceHost extends GetEffectiveTypeRootsHost {
+    interface LanguageServiceHost extends GetEffectiveTypeRootsHost, MinimalResolutionCacheHost {
         getCompilationSettings(): CompilerOptions;
         getNewLine?(): string;
         getProjectVersion?(): string;
@@ -5694,9 +5731,9 @@ declare namespace ts {
         error?(s: string): void;
         useCaseSensitiveFileNames?(): boolean;
         readDirectory?(path: string, extensions?: readonly string[], exclude?: readonly string[], include?: readonly string[], depth?: number): string[];
-        readFile?(path: string, encoding?: string): string | undefined;
         realpath?(path: string): string;
-        fileExists?(path: string): boolean;
+        readFile(path: string, encoding?: string): string | undefined;
+        fileExists(path: string): boolean;
         getTypeRootsVersion?(): number;
         resolveModuleNames?(moduleNames: string[], containingFile: string, reusedNames: string[] | undefined, redirectedReference: ResolvedProjectReference | undefined, options: CompilerOptions, containingSourceFile?: SourceFile): (ResolvedModule | undefined)[];
         getResolvedModuleWithFailedLookupLocationsFromCache?(modulename: string, containingFile: string, resolutionMode?: ModuleKind.CommonJS | ModuleKind.ESNext): ResolvedModuleWithFailedLookupLocations | undefined;
@@ -6748,30 +6785,36 @@ declare namespace ts {
          * the SourceFile if was not found in the registry.
          *
          * @param fileName The name of the file requested
-         * @param compilationSettings Some compilation settings like target affects the
+         * @param compilationSettingsOrHost Some compilation settings like target affects the
          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
-         * multiple copies of the same file for different compilation settings.
+         * multiple copies of the same file for different compilation settings. A minimal
+         * resolution cache is needed to fully define a source file's shape when
+         * the compilation settings include `module: node12`+, so providing a cache host
+         * object should be preferred. A common host is a language service `ConfiguredProject`.
          * @param scriptSnapshot Text of the file. Only used if the file was not found
          * in the registry and a new one was created.
          * @param version Current version of the file. Only used if the file was not found
          * in the registry and a new one was created.
          */
-        acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
-        acquireDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        acquireDocument(fileName: string, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        acquireDocumentWithKey(fileName: string, path: Path, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
         /**
          * Request an updated version of an already existing SourceFile with a given fileName
          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
          * to get an updated SourceFile.
          *
          * @param fileName The name of the file requested
-         * @param compilationSettings Some compilation settings like target affects the
+         * @param compilationSettingsOrHost Some compilation settings like target affects the
          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
-         * multiple copies of the same file for different compilation settings.
+         * multiple copies of the same file for different compilation settings. A minimal
+         * resolution cache is needed to fully define a source file's shape when
+         * the compilation settings include `module: node12`+, so providing a cache host
+         * object should be preferred. A common host is a language service `ConfiguredProject`.
          * @param scriptSnapshot Text of the file.
          * @param version Current version of the file.
          */
-        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
-        updateDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        updateDocument(fileName: string, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        updateDocumentWithKey(fileName: string, path: Path, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
         getKeyForCompilationSettings(settings: CompilerOptions): DocumentRegistryBucketKey;
         /**
          * Informs the DocumentRegistry that a file is not needed any longer.
@@ -6833,7 +6876,7 @@ declare namespace ts {
     function displayPartsToString(displayParts: SymbolDisplayPart[] | undefined): string;
     function getDefaultCompilerOptions(): CompilerOptions;
     function getSupportedCodeFixes(): string[];
-    function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTarget: ScriptTarget, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile;
+    function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTargetOrOptions: ScriptTarget | CreateSourceFileOptions, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile;
     function updateLanguageServiceSourceFile(sourceFile: SourceFile, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange | undefined, aggressiveChecks?: boolean): SourceFile;
     function createLanguageService(host: LanguageServiceHost, documentRegistry?: DocumentRegistry, syntaxOnlyOrLanguageServiceMode?: boolean | LanguageServiceMode): LanguageService;
     /**
diff --git a/tests/baselines/reference/api/typescript.d.ts b/tests/baselines/reference/api/typescript.d.ts
index 0f71e03eef9..e78e7d779b8 100644
--- a/tests/baselines/reference/api/typescript.d.ts
+++ b/tests/baselines/reference/api/typescript.d.ts
@@ -2888,6 +2888,20 @@ declare namespace ts {
         Node12 = 3,
         NodeNext = 99
     }
+    export enum ModuleDetectionKind {
+        /**
+         * Files with imports, exports and/or import.meta are considered modules
+         */
+        Legacy = 1,
+        /**
+         * Legacy, but also files with jsx under react-jsx or react-jsxdev and esm mode files under moduleResolution: node12+
+         */
+        Auto = 2,
+        /**
+         * Consider all non-declaration files modules, regardless of present syntax
+         */
+        Force = 3
+    }
     export interface PluginImport {
         name: string;
     }
@@ -2959,6 +2973,7 @@ declare namespace ts {
         maxNodeModuleJsDepth?: number;
         module?: ModuleKind;
         moduleResolution?: ModuleResolutionKind;
+        moduleDetection?: ModuleDetectionKind;
         newLine?: NewLineKind;
         noEmit?: boolean;
         noEmitHelpers?: boolean;
@@ -3146,6 +3161,13 @@ declare namespace ts {
         getDirectories?(path: string): string[];
         useCaseSensitiveFileNames?: boolean | (() => boolean);
     }
+    /**
+     * Used by services to specify the minimum host area required to set up source files under any compilation settings
+     */
+    export interface MinimalResolutionCacheHost extends ModuleResolutionHost {
+        getCompilationSettings(): CompilerOptions;
+        getCompilerHost?(): CompilerHost | undefined;
+    }
     /**
      * Represents the result of module resolution.
      * Module resolution will pick up tsx/jsx/js files even if '--jsx' and '--allowJs' are turned off.
@@ -3221,8 +3243,8 @@ declare namespace ts {
         readonly failedLookupLocations: string[];
     }
     export interface CompilerHost extends ModuleResolutionHost {
-        getSourceFile(fileName: string, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
-        getSourceFileByPath?(fileName: string, path: Path, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
+        getSourceFile(fileName: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
+        getSourceFileByPath?(fileName: string, path: Path, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
         getCancellationToken?(): CancellationToken;
         getDefaultLibFileName(options: CompilerOptions): string;
         getDefaultLibLocation?(): string;
@@ -4776,7 +4798,22 @@ declare namespace ts {
      * that they appear in the source code. The language service depends on this property to locate nodes by position.
      */
     export function forEachChild<T>(node: Node, cbNode: (node: Node) => T | undefined, cbNodes?: (nodes: NodeArray<Node>) => T | undefined): T | undefined;
-    export function createSourceFile(fileName: string, sourceText: string, languageVersion: ScriptTarget, setParentNodes?: boolean, scriptKind?: ScriptKind): SourceFile;
+    export interface CreateSourceFileOptions {
+        languageVersion: ScriptTarget;
+        /**
+         * Controls the format the file is detected as - this can be derived from only the path
+         * and files on disk, but needs to be done with a module resolution cache in scope to be performant.
+         * This is usually `undefined` for compilations that do not have `moduleResolution` values of `node12` or `nodenext`.
+         */
+        impliedNodeFormat?: ModuleKind.ESNext | ModuleKind.CommonJS;
+        /**
+         * Controls how module-y-ness is set for the given file. Usually the result of calling
+         * `getSetExternalModuleIndicator` on a valid `CompilerOptions` object. If not present, the default
+         * check specified by `isFileProbablyExternalModule` will be used to set the field.
+         */
+        setExternalModuleIndicator?: (file: SourceFile) => void;
+    }
+    export function createSourceFile(fileName: string, sourceText: string, languageVersionOrOptions: ScriptTarget | CreateSourceFileOptions, setParentNodes?: boolean, scriptKind?: ScriptKind): SourceFile;
     export function parseIsolatedEntityName(text: string, languageVersion: ScriptTarget): EntityName | undefined;
     /**
      * Parse json text into SyntaxTree and return node and parse errors if any
@@ -5676,7 +5713,7 @@ declare namespace ts {
         set(response: CompletionInfo): void;
         clear(): void;
     }
-    interface LanguageServiceHost extends GetEffectiveTypeRootsHost {
+    interface LanguageServiceHost extends GetEffectiveTypeRootsHost, MinimalResolutionCacheHost {
         getCompilationSettings(): CompilerOptions;
         getNewLine?(): string;
         getProjectVersion?(): string;
@@ -5694,9 +5731,9 @@ declare namespace ts {
         error?(s: string): void;
         useCaseSensitiveFileNames?(): boolean;
         readDirectory?(path: string, extensions?: readonly string[], exclude?: readonly string[], include?: readonly string[], depth?: number): string[];
-        readFile?(path: string, encoding?: string): string | undefined;
         realpath?(path: string): string;
-        fileExists?(path: string): boolean;
+        readFile(path: string, encoding?: string): string | undefined;
+        fileExists(path: string): boolean;
         getTypeRootsVersion?(): number;
         resolveModuleNames?(moduleNames: string[], containingFile: string, reusedNames: string[] | undefined, redirectedReference: ResolvedProjectReference | undefined, options: CompilerOptions, containingSourceFile?: SourceFile): (ResolvedModule | undefined)[];
         getResolvedModuleWithFailedLookupLocationsFromCache?(modulename: string, containingFile: string, resolutionMode?: ModuleKind.CommonJS | ModuleKind.ESNext): ResolvedModuleWithFailedLookupLocations | undefined;
@@ -6748,30 +6785,36 @@ declare namespace ts {
          * the SourceFile if was not found in the registry.
          *
          * @param fileName The name of the file requested
-         * @param compilationSettings Some compilation settings like target affects the
+         * @param compilationSettingsOrHost Some compilation settings like target affects the
          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
-         * multiple copies of the same file for different compilation settings.
+         * multiple copies of the same file for different compilation settings. A minimal
+         * resolution cache is needed to fully define a source file's shape when
+         * the compilation settings include `module: node12`+, so providing a cache host
+         * object should be preferred. A common host is a language service `ConfiguredProject`.
          * @param scriptSnapshot Text of the file. Only used if the file was not found
          * in the registry and a new one was created.
          * @param version Current version of the file. Only used if the file was not found
          * in the registry and a new one was created.
          */
-        acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
-        acquireDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        acquireDocument(fileName: string, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        acquireDocumentWithKey(fileName: string, path: Path, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
         /**
          * Request an updated version of an already existing SourceFile with a given fileName
          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
          * to get an updated SourceFile.
          *
          * @param fileName The name of the file requested
-         * @param compilationSettings Some compilation settings like target affects the
+         * @param compilationSettingsOrHost Some compilation settings like target affects the
          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
-         * multiple copies of the same file for different compilation settings.
+         * multiple copies of the same file for different compilation settings. A minimal
+         * resolution cache is needed to fully define a source file's shape when
+         * the compilation settings include `module: node12`+, so providing a cache host
+         * object should be preferred. A common host is a language service `ConfiguredProject`.
          * @param scriptSnapshot Text of the file.
          * @param version Current version of the file.
          */
-        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
-        updateDocumentWithKey(fileName: string, path: Path, compilationSettings: CompilerOptions, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        updateDocument(fileName: string, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
+        updateDocumentWithKey(fileName: string, path: Path, compilationSettingsOrHost: CompilerOptions | MinimalResolutionCacheHost, key: DocumentRegistryBucketKey, scriptSnapshot: IScriptSnapshot, version: string, scriptKind?: ScriptKind): SourceFile;
         getKeyForCompilationSettings(settings: CompilerOptions): DocumentRegistryBucketKey;
         /**
          * Informs the DocumentRegistry that a file is not needed any longer.
@@ -6833,7 +6876,7 @@ declare namespace ts {
     function displayPartsToString(displayParts: SymbolDisplayPart[] | undefined): string;
     function getDefaultCompilerOptions(): CompilerOptions;
     function getSupportedCodeFixes(): string[];
-    function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTarget: ScriptTarget, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile;
+    function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTargetOrOptions: ScriptTarget | CreateSourceFileOptions, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile;
     function updateLanguageServiceSourceFile(sourceFile: SourceFile, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange | undefined, aggressiveChecks?: boolean): SourceFile;
     function createLanguageService(host: LanguageServiceHost, documentRegistry?: DocumentRegistry, syntaxOnlyOrLanguageServiceMode?: boolean | LanguageServiceMode): LanguageService;
     /**
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=auto).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).js
new file mode 100644
index 00000000000..758128360f8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).js
@@ -0,0 +1,46 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.jsx]
+"use strict";
+exports.__esModule = true;
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return <div>
+            {/* missing */}
+            {null /* preserved */}
+            {
+            // ??? 1
+            }
+            {// ??? 2
+            }
+            {// ??? 3
+            }
+            {
+            // ??? 4
+            /* ??? 5 */ }
+        </div>;
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=force).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).types
new file mode 100644
index 00000000000..113455cf53d
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=commonjs,moduledetection=legacy).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : error
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).js
new file mode 100644
index 00000000000..f68279f3f58
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).js
@@ -0,0 +1,44 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.jsx]
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return <div>
+            {/* missing */}
+            {null /* preserved */}
+            {
+            // ??? 1
+            }
+            {// ??? 2
+            }
+            {// ??? 3
+            }
+            {
+            // ??? 4
+            /* ??? 5 */ }
+        </div>;
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).types
new file mode 100644
index 00000000000..113455cf53d
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=auto).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : error
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).js
new file mode 100644
index 00000000000..ea4ff413244
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).js
@@ -0,0 +1,54 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.jsx]
+System.register([], function (exports_1, context_1) {
+    "use strict";
+    var Component;
+    var __moduleName = context_1 && context_1.id;
+    return {
+        setters: [],
+        execute: function () {
+            Component = /** @class */ (function () {
+                function Component() {
+                }
+                Component.prototype.render = function () {
+                    return <div>
+            {/* missing */}
+            {null /* preserved */}
+            {
+                        // ??? 1
+                        }
+            {// ??? 2
+                        }
+            {// ??? 3
+                        }
+            {
+                        // ??? 4
+                        /* ??? 5 */ }
+        </div>;
+                };
+                return Component;
+            }());
+        }
+    };
+});
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).types
new file mode 100644
index 00000000000..113455cf53d
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=force).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : error
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).js
new file mode 100644
index 00000000000..f68279f3f58
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).js
@@ -0,0 +1,44 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.jsx]
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return <div>
+            {/* missing */}
+            {null /* preserved */}
+            {
+            // ??? 1
+            }
+            {// ??? 2
+            }
+            {// ??? 3
+            }
+            {
+            // ??? 4
+            /* ??? 5 */ }
+        </div>;
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).types
new file mode 100644
index 00000000000..113455cf53d
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=preserve,module=system,moduledetection=legacy).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : error
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).errors.txt
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).errors.txt
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).errors.txt
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=auto).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).errors.txt
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).errors.txt
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).errors.txt
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).js
new file mode 100644
index 00000000000..f271b199ed6
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).js
@@ -0,0 +1,33 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+"use strict";
+exports.__esModule = true;
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return React.createElement("div", null, null /* preserved */);
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).symbols
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).symbols
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).symbols
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=force).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).errors.txt
new file mode 100644
index 00000000000..388601f8ae8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).errors.txt
@@ -0,0 +1,26 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,17): error TS2304: Cannot find name 'React'.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                    ~~~
+!!! error TS2304: Cannot find name 'React'.
+                {/* missing */}
+                {null/* preserved */}
+                {
+                    // ??? 1
+                }
+                { // ??? 2
+                }
+                {// ??? 3
+                }
+                {
+                    // ??? 4
+                /* ??? 5 */}
+            </div>;
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=commonjs,moduledetection=legacy).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).errors.txt
new file mode 100644
index 00000000000..388601f8ae8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).errors.txt
@@ -0,0 +1,26 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,17): error TS2304: Cannot find name 'React'.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                    ~~~
+!!! error TS2304: Cannot find name 'React'.
+                {/* missing */}
+                {null/* preserved */}
+                {
+                    // ??? 1
+                }
+                { // ??? 2
+                }
+                {// ??? 3
+                }
+                {
+                    // ??? 4
+                /* ??? 5 */}
+            </div>;
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).js
new file mode 100644
index 00000000000..5cc6523cd07
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).js
@@ -0,0 +1,31 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return React.createElement("div", null, null /* preserved */);
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=auto).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).errors.txt
new file mode 100644
index 00000000000..388601f8ae8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).errors.txt
@@ -0,0 +1,26 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,17): error TS2304: Cannot find name 'React'.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                    ~~~
+!!! error TS2304: Cannot find name 'React'.
+                {/* missing */}
+                {null/* preserved */}
+                {
+                    // ??? 1
+                }
+                { // ??? 2
+                }
+                {// ??? 3
+                }
+                {
+                    // ??? 4
+                /* ??? 5 */}
+            </div>;
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).js
new file mode 100644
index 00000000000..ca668d2af98
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).js
@@ -0,0 +1,41 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+System.register([], function (exports_1, context_1) {
+    "use strict";
+    var Component;
+    var __moduleName = context_1 && context_1.id;
+    return {
+        setters: [],
+        execute: function () {
+            Component = /** @class */ (function () {
+                function Component() {
+                }
+                Component.prototype.render = function () {
+                    return React.createElement("div", null, null /* preserved */);
+                };
+                return Component;
+            }());
+        }
+    };
+});
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=force).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).errors.txt
new file mode 100644
index 00000000000..388601f8ae8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).errors.txt
@@ -0,0 +1,26 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,17): error TS2304: Cannot find name 'React'.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                    ~~~
+!!! error TS2304: Cannot find name 'React'.
+                {/* missing */}
+                {null/* preserved */}
+                {
+                    // ??? 1
+                }
+                { // ??? 2
+                }
+                {// ??? 3
+                }
+                {
+                    // ??? 4
+                /* ??? 5 */}
+            </div>;
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).js
new file mode 100644
index 00000000000..5cc6523cd07
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).js
@@ -0,0 +1,31 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return React.createElement("div", null, null /* preserved */);
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).types
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).types
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react,module=system,moduledetection=legacy).types
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).errors.txt
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).errors.txt
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).errors.txt
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).js
new file mode 100644
index 00000000000..f7712f000b8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).js
@@ -0,0 +1,34 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+"use strict";
+exports.__esModule = true;
+var jsx_runtime_1 = require("react/jsx-runtime");
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return (0, jsx_runtime_1.jsx)("div", { children: null /* preserved */ });
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=auto).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).errors.txt
new file mode 100644
index 00000000000..0f9a371c783
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2307: Cannot find module 'react/jsx-runtime' or its corresponding type declarations.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2307: Cannot find module 'react/jsx-runtime' or its corresponding type declarations.
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).js
new file mode 100644
index 00000000000..f7712f000b8
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).js
@@ -0,0 +1,34 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+"use strict";
+exports.__esModule = true;
+var jsx_runtime_1 = require("react/jsx-runtime");
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return (0, jsx_runtime_1.jsx)("div", { children: null /* preserved */ });
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=force).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).errors.txt
new file mode 100644
index 00000000000..0f9a371c783
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2307: Cannot find module 'react/jsx-runtime' or its corresponding type declarations.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2307: Cannot find module 'react/jsx-runtime' or its corresponding type declarations.
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=commonjs,moduledetection=legacy).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).errors.txt
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).errors.txt
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).errors.txt
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).js
new file mode 100644
index 00000000000..223fb4a66ba
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).js
@@ -0,0 +1,45 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+System.register(["react/jsx-runtime"], function (exports_1, context_1) {
+    "use strict";
+    var jsx_runtime_1, Component;
+    var __moduleName = context_1 && context_1.id;
+    return {
+        setters: [
+            function (jsx_runtime_1_1) {
+                jsx_runtime_1 = jsx_runtime_1_1;
+            }
+        ],
+        execute: function () {
+            Component = /** @class */ (function () {
+                function Component() {
+                }
+                Component.prototype.render = function () {
+                    return _jsx("div", { children: null /* preserved */ });
+                };
+                return Component;
+            }());
+        }
+    };
+});
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=auto).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).errors.txt
new file mode 100644
index 00000000000..610a0fa29c5
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2792: Cannot find module 'react/jsx-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2792: Cannot find module 'react/jsx-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).js
new file mode 100644
index 00000000000..223fb4a66ba
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).js
@@ -0,0 +1,45 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+System.register(["react/jsx-runtime"], function (exports_1, context_1) {
+    "use strict";
+    var jsx_runtime_1, Component;
+    var __moduleName = context_1 && context_1.id;
+    return {
+        setters: [
+            function (jsx_runtime_1_1) {
+                jsx_runtime_1 = jsx_runtime_1_1;
+            }
+        ],
+        execute: function () {
+            Component = /** @class */ (function () {
+                function Component() {
+                }
+                Component.prototype.render = function () {
+                    return _jsx("div", { children: null /* preserved */ });
+                };
+                return Component;
+            }());
+        }
+    };
+});
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=force).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).errors.txt
new file mode 100644
index 00000000000..610a0fa29c5
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2792: Cannot find module 'react/jsx-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2792: Cannot find module 'react/jsx-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsx,module=system,moduledetection=legacy).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).errors.txt
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).errors.txt
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).errors.txt
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).js
new file mode 100644
index 00000000000..810347d948d
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).js
@@ -0,0 +1,35 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+"use strict";
+exports.__esModule = true;
+var jsx_dev_runtime_1 = require("react/jsx-dev-runtime");
+var _jsxFileName = "tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx";
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return (0, jsx_dev_runtime_1.jsxDEV)("div", { children: null /* preserved */ }, void 0, false, { fileName: _jsxFileName, lineNumber: 5, columnNumber: 15 }, this);
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).errors.txt
new file mode 100644
index 00000000000..7ecc135630b
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2307: Cannot find module 'react/jsx-dev-runtime' or its corresponding type declarations.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2307: Cannot find module 'react/jsx-dev-runtime' or its corresponding type declarations.
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).js
new file mode 100644
index 00000000000..810347d948d
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).js
@@ -0,0 +1,35 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+"use strict";
+exports.__esModule = true;
+var jsx_dev_runtime_1 = require("react/jsx-dev-runtime");
+var _jsxFileName = "tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx";
+var Component = /** @class */ (function () {
+    function Component() {
+    }
+    Component.prototype.render = function () {
+        return (0, jsx_dev_runtime_1.jsxDEV)("div", { children: null /* preserved */ }, void 0, false, { fileName: _jsxFileName, lineNumber: 5, columnNumber: 15 }, this);
+    };
+    return Component;
+}());
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).errors.txt
new file mode 100644
index 00000000000..7ecc135630b
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2307: Cannot find module 'react/jsx-dev-runtime' or its corresponding type declarations.
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2307: Cannot find module 'react/jsx-dev-runtime' or its corresponding type declarations.
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).errors.txt
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).errors.txt
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).errors.txt
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).js
new file mode 100644
index 00000000000..dd74fc86a3c
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).js
@@ -0,0 +1,46 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+System.register(["react/jsx-dev-runtime"], function (exports_1, context_1) {
+    "use strict";
+    var jsx_dev_runtime_1, _jsxFileName, Component;
+    var __moduleName = context_1 && context_1.id;
+    return {
+        setters: [
+            function (jsx_dev_runtime_1_1) {
+                jsx_dev_runtime_1 = jsx_dev_runtime_1_1;
+            }
+        ],
+        execute: function () {
+            _jsxFileName = "tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx";
+            Component = /** @class */ (function () {
+                function Component() {
+                }
+                Component.prototype.render = function () {
+                    return _jsxDEV("div", { children: null /* preserved */ }, void 0, false, { fileName: _jsxFileName, lineNumber: 5, columnNumber: 15 }, this);
+                };
+                return Component;
+            }());
+        }
+    };
+});
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).errors.txt
new file mode 100644
index 00000000000..072fbae9425
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2792: Cannot find module 'react/jsx-dev-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2792: Cannot find module 'react/jsx-dev-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).js
new file mode 100644
index 00000000000..dd74fc86a3c
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).js
@@ -0,0 +1,46 @@
+//// [commentsOnJSXExpressionsArePreserved.tsx]
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+    render() {
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
+
+//// [commentsOnJSXExpressionsArePreserved.js]
+System.register(["react/jsx-dev-runtime"], function (exports_1, context_1) {
+    "use strict";
+    var jsx_dev_runtime_1, _jsxFileName, Component;
+    var __moduleName = context_1 && context_1.id;
+    return {
+        setters: [
+            function (jsx_dev_runtime_1_1) {
+                jsx_dev_runtime_1 = jsx_dev_runtime_1_1;
+            }
+        ],
+        execute: function () {
+            _jsxFileName = "tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx";
+            Component = /** @class */ (function () {
+                function Component() {
+                }
+                Component.prototype.render = function () {
+                    return _jsxDEV("div", { children: null /* preserved */ }, void 0, false, { fileName: _jsxFileName, lineNumber: 5, columnNumber: 15 }, this);
+                };
+                return Component;
+            }());
+        }
+    };
+});
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).errors.txt b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).errors.txt
new file mode 100644
index 00000000000..072fbae9425
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).errors.txt
@@ -0,0 +1,39 @@
+tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx(5,16): error TS2792: Cannot find module 'react/jsx-dev-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+
+
+==== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx (1 errors) ====
+    // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+    namespace JSX {}
+    class Component {
+        render() {
+            return <div>
+                   ~~~~~
+                {/* missing */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {null/* preserved */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 1
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                { // ??? 2
+    ~~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {// ??? 3
+    ~~~~~~~~~~~~~~~~~~~~~
+                }
+    ~~~~~~~~~~~~~
+                {
+    ~~~~~~~~~~~~~
+                    // ??? 4
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+                /* ??? 5 */}
+    ~~~~~~~~~~~~~~~~~~~~~~~~
+            </div>;
+    ~~~~~~~~~~~~~~
+!!! error TS2792: Cannot find module 'react/jsx-dev-runtime'. Did you mean to set the 'moduleResolution' option to 'node', or to add aliases to the 'paths' option?
+        }
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).js b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).js
similarity index 100%
rename from tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system).js
rename to tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).js
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).symbols b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).symbols
new file mode 100644
index 00000000000..95b7eeda062
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+>JSX : Symbol(JSX, Decl(commentsOnJSXExpressionsArePreserved.tsx, 0, 0))
+
+class Component {
+>Component : Symbol(Component, Decl(commentsOnJSXExpressionsArePreserved.tsx, 1, 16))
+
+    render() {
+>render : Symbol(Component.render, Decl(commentsOnJSXExpressionsArePreserved.tsx, 2, 17))
+
+        return <div>
+            {/* missing */}
+            {null/* preserved */}
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+    }
+}
diff --git a/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).types b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).types
new file mode 100644
index 00000000000..5acb76daa70
--- /dev/null
+++ b/tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).types
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx ===
+// file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
+namespace JSX {}
+class Component {
+>Component : Component
+
+    render() {
+>render : () => any
+
+        return <div>
+><div>            {/* missing */}            {null/* preserved */}            {                // ??? 1            }            { // ??? 2            }            {// ??? 3            }            {                // ??? 4            /* ??? 5 */}        </div> : any
+>div : any
+
+            {/* missing */}
+            {null/* preserved */}
+>null : null
+            {
+                // ??? 1
+            }
+            { // ??? 2
+            }
+            {// ??? 3
+            }
+            {
+                // ??? 4
+            /* ??? 5 */}
+        </div>;
+>div : any
+    }
+}
diff --git a/tests/baselines/reference/moduleResolutionWithoutExtension5.js b/tests/baselines/reference/moduleResolutionWithoutExtension5.js
index b79c4d0d548..8c2854da5f9 100644
--- a/tests/baselines/reference/moduleResolutionWithoutExtension5.js
+++ b/tests/baselines/reference/moduleResolutionWithoutExtension5.js
@@ -5,3 +5,4 @@ import("./foo").then(x => x); // should error, ask for extension
 //// [buzz.mjs]
 // Extensionless relative path dynamic import in an ES module
 import("./foo").then(x => x); // should error, ask for extension
+export {};
diff --git a/tests/baselines/reference/showConfig/Shows tsconfig for single option/moduleDetection/tsconfig.json b/tests/baselines/reference/showConfig/Shows tsconfig for single option/moduleDetection/tsconfig.json
new file mode 100644
index 00000000000..1dfb65063ce
--- /dev/null
+++ b/tests/baselines/reference/showConfig/Shows tsconfig for single option/moduleDetection/tsconfig.json	
@@ -0,0 +1,5 @@
+{
+    "compilerOptions": {
+        "moduleDetection": "auto"
+    }
+}
diff --git a/tests/baselines/reference/tsConfig/Default initialized TSConfig/tsconfig.json b/tests/baselines/reference/tsConfig/Default initialized TSConfig/tsconfig.json
index 4bbabc7934a..e477a6d2d0f 100644
--- a/tests/baselines/reference/tsConfig/Default initialized TSConfig/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Default initialized TSConfig/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with advanced options/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with advanced options/tsconfig.json
index c7bdea62026..79809e53b7f 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with advanced options/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with advanced options/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with boolean value compiler options/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with boolean value compiler options/tsconfig.json
index 93bc4899b98..ec639ce04b5 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with boolean value compiler options/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with boolean value compiler options/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with enum value compiler options/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with enum value compiler options/tsconfig.json
index f9da788b908..0870344d037 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with enum value compiler options/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with enum value compiler options/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with files options/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with files options/tsconfig.json
index 17874b6315f..eb7b0a8f38d 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with files options/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with files options/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option value/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option value/tsconfig.json
index 8008a065b8e..8ebd3a89cb7 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option value/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option value/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option/tsconfig.json
index 4bbabc7934a..e477a6d2d0f 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options with enum value/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options with enum value/tsconfig.json
index 32e837555de..89fa7a41f98 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options with enum value/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options with enum value/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options/tsconfig.json b/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options/tsconfig.json
index 0d6d23dccbc..0d26d725aab 100644
--- a/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options/tsconfig.json	
+++ b/tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options/tsconfig.json	
@@ -22,6 +22,7 @@
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/declarationDir-is-specified.js b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/declarationDir-is-specified.js
index db8709deef5..6726890d7f2 100644
--- a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/declarationDir-is-specified.js
+++ b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/declarationDir-is-specified.js
@@ -43,6 +43,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "amd",                                     /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-and-declarationDir-is-specified.js b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-and-declarationDir-is-specified.js
index 1a96cb83458..4eb22035026 100644
--- a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-and-declarationDir-is-specified.js
+++ b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-and-declarationDir-is-specified.js
@@ -43,6 +43,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "amd",                                     /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-is-specified.js b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-is-specified.js
index 2b40916780b..bb93a691e97 100644
--- a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-is-specified.js
+++ b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-is-specified.js
@@ -43,6 +43,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "amd",                                     /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/with-outFile.js b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/with-outFile.js
index a460f97095f..bcfb9f12b5a 100644
--- a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/with-outFile.js
+++ b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/with-outFile.js
@@ -43,6 +43,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "amd",                                     /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified-with-declaration-enabled.js b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified-with-declaration-enabled.js
index ed2364fbe47..c123aec942b 100644
--- a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified-with-declaration-enabled.js
+++ b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified-with-declaration-enabled.js
@@ -43,6 +43,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "amd",                                     /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified.js b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified.js
index daa4a50372c..346ddcce15a 100644
--- a/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified.js
+++ b/tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified.js
@@ -43,6 +43,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
     // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
     // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
 
     /* Modules */
     "module": "amd",                                     /* Specify what module code is generated. */
diff --git a/tests/baselines/reference/tsxReactEmit8(jsx=react-jsx).js b/tests/baselines/reference/tsxReactEmit8(jsx=react-jsx).js
index 4b2ad79559d..7c5e74e00ee 100644
--- a/tests/baselines/reference/tsxReactEmit8(jsx=react-jsx).js
+++ b/tests/baselines/reference/tsxReactEmit8(jsx=react-jsx).js
@@ -6,6 +6,7 @@
 
 
 //// [tsxReactEmit8.js]
+import { jsx as _jsx } from "react/jsx-runtime";
 /// <reference path="react16.d.ts" />
 _jsx("div", { children: "1" });
 _jsx("div", { children: "2" }, "key-attr");
diff --git a/tests/baselines/reference/tsxReactEmit8(jsx=react-jsxdev).js b/tests/baselines/reference/tsxReactEmit8(jsx=react-jsxdev).js
index 898c4d98862..12ac49d0452 100644
--- a/tests/baselines/reference/tsxReactEmit8(jsx=react-jsxdev).js
+++ b/tests/baselines/reference/tsxReactEmit8(jsx=react-jsxdev).js
@@ -6,6 +6,7 @@
 
 
 //// [tsxReactEmit8.js]
+import { jsxDEV as _jsxDEV } from "react/jsx-dev-runtime";
 const _jsxFileName = "tests/cases/conformance/jsx/tsxReactEmit8.tsx";
 /// <reference path="react16.d.ts" />
 _jsxDEV("div", { children: "1" }, void 0, false, { fileName: _jsxFileName, lineNumber: 1, columnNumber: 1 }, this);
diff --git a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).js b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).js
index 9314082e933..dee4ee2ddfc 100644
--- a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).js
+++ b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).js
@@ -33,6 +33,7 @@ let x: TodoListProps;
 
 
 //// [tsxSpreadChildrenInvalidType.js]
+import { jsx as _jsx, jsxs as _jsxs } from "react/jsx-runtime";
 function Todo(prop) {
     return _jsx("div", { children: prop.key.toString() + prop.todo });
 }
diff --git a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).symbols b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).symbols
index 5e41936f306..c3be731e55e 100644
--- a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).symbols
+++ b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).symbols
@@ -38,7 +38,6 @@ function Todo(prop: { key: number, todo: string }) {
 >todo : Symbol(todo, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 34))
 
     return <div>{prop.key.toString() + prop.todo}</div>;
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 >prop.key.toString : Symbol(Number.toString, Decl(lib.es5.d.ts, --, --))
 >prop.key : Symbol(key, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 21))
 >prop : Symbol(prop, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 14))
@@ -47,7 +46,6 @@ function Todo(prop: { key: number, todo: string }) {
 >prop.todo : Symbol(todo, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 34))
 >prop : Symbol(prop, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 14))
 >todo : Symbol(todo, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 34))
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 }
 function TodoList({ todos }: TodoListProps) {
 >TodoList : Symbol(TodoList, Decl(tsxSpreadChildrenInvalidType.tsx, 17, 1))
@@ -55,8 +53,6 @@ function TodoList({ todos }: TodoListProps) {
 >TodoListProps : Symbol(TodoListProps, Decl(tsxSpreadChildrenInvalidType.tsx, 11, 1))
 
     return <div>
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
-
         {...<Todo key={todos[0].id} todo={todos[0].todo} />}
 >Todo : Symbol(Todo, Decl(tsxSpreadChildrenInvalidType.tsx, 14, 1))
 >key : Symbol(key, Decl(tsxSpreadChildrenInvalidType.tsx, 20, 17))
@@ -69,7 +65,6 @@ function TodoList({ todos }: TodoListProps) {
 >todo : Symbol(TodoProp.todo, Decl(tsxSpreadChildrenInvalidType.tsx, 9, 15))
 
     </div>;
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 }
 function TodoListNoError({ todos }: TodoListProps) {
 >TodoListNoError : Symbol(TodoListNoError, Decl(tsxSpreadChildrenInvalidType.tsx, 22, 1))
@@ -78,8 +73,6 @@ function TodoListNoError({ todos }: TodoListProps) {
 
     // any is not checked
     return <div>
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
-
         {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}
 >Todo : Symbol(Todo, Decl(tsxSpreadChildrenInvalidType.tsx, 14, 1))
 >key : Symbol(key, Decl(tsxSpreadChildrenInvalidType.tsx, 26, 18))
@@ -92,7 +85,6 @@ function TodoListNoError({ todos }: TodoListProps) {
 >todo : Symbol(TodoProp.todo, Decl(tsxSpreadChildrenInvalidType.tsx, 9, 15))
 
     </div>;
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 }
 let x: TodoListProps;
 >x : Symbol(x, Decl(tsxSpreadChildrenInvalidType.tsx, 29, 3))
diff --git a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).types b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).types
index b8eb0487037..542fa2c7fca 100644
--- a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).types
+++ b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es2015).types
@@ -21,13 +21,13 @@ interface TodoListProps {
 >todos : TodoProp[]
 }
 function Todo(prop: { key: number, todo: string }) {
->Todo : (prop: {    key: number;    todo: string;}) => JSX.Element
+>Todo : (prop: {    key: number;    todo: string;}) => any
 >prop : { key: number; todo: string; }
 >key : number
 >todo : string
 
     return <div>{prop.key.toString() + prop.todo}</div>;
-><div>{prop.key.toString() + prop.todo}</div> : JSX.Element
+><div>{prop.key.toString() + prop.todo}</div> : any
 >div : any
 >prop.key.toString() + prop.todo : string
 >prop.key.toString() : string
@@ -42,16 +42,16 @@ function Todo(prop: { key: number, todo: string }) {
 >div : any
 }
 function TodoList({ todos }: TodoListProps) {
->TodoList : ({ todos }: TodoListProps) => JSX.Element
+>TodoList : ({ todos }: TodoListProps) => any
 >todos : TodoProp[]
 
     return <div>
-><div>        {...<Todo key={todos[0].id} todo={todos[0].todo} />}    </div> : JSX.Element
+><div>        {...<Todo key={todos[0].id} todo={todos[0].todo} />}    </div> : any
 >div : any
 
         {...<Todo key={todos[0].id} todo={todos[0].todo} />}
-><Todo key={todos[0].id} todo={todos[0].todo} /> : JSX.Element
->Todo : (prop: { key: number; todo: string; }) => JSX.Element
+><Todo key={todos[0].id} todo={todos[0].todo} /> : any
+>Todo : (prop: { key: number; todo: string; }) => any
 >key : number
 >todos[0].id : number
 >todos[0] : TodoProp
@@ -69,19 +69,19 @@ function TodoList({ todos }: TodoListProps) {
 >div : any
 }
 function TodoListNoError({ todos }: TodoListProps) {
->TodoListNoError : ({ todos }: TodoListProps) => JSX.Element
+>TodoListNoError : ({ todos }: TodoListProps) => any
 >todos : TodoProp[]
 
     // any is not checked
     return <div>
-><div>        {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}    </div> : JSX.Element
+><div>        {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}    </div> : any
 >div : any
 
         {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}
 >(<Todo key={todos[0].id} todo={todos[0].todo} /> as any) : any
 ><Todo key={todos[0].id} todo={todos[0].todo} /> as any : any
-><Todo key={todos[0].id} todo={todos[0].todo} /> : JSX.Element
->Todo : (prop: { key: number; todo: string; }) => JSX.Element
+><Todo key={todos[0].id} todo={todos[0].todo} /> : any
+>Todo : (prop: { key: number; todo: string; }) => any
 >key : number
 >todos[0].id : number
 >todos[0] : TodoProp
@@ -102,7 +102,7 @@ let x: TodoListProps;
 >x : TodoListProps
 
     <TodoList {...x}/>
-><TodoList {...x}/> : JSX.Element
->TodoList : ({ todos }: TodoListProps) => JSX.Element
+><TodoList {...x}/> : any
+>TodoList : ({ todos }: TodoListProps) => any
 >x : TodoListProps
 
diff --git a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).js b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).js
index bf484ee6c15..8ebd589281c 100644
--- a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).js
+++ b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).js
@@ -33,6 +33,7 @@ let x: TodoListProps;
 
 
 //// [tsxSpreadChildrenInvalidType.js]
+"use strict";
 var __assign = (this && this.__assign) || function () {
     __assign = Object.assign || function(t) {
         for (var s, i = 1, n = arguments.length; i < n; i++) {
@@ -53,17 +54,19 @@ var __spreadArray = (this && this.__spreadArray) || function (to, from, pack) {
     }
     return to.concat(ar || Array.prototype.slice.call(from));
 };
+Object.defineProperty(exports, "__esModule", { value: true });
+var jsx_runtime_1 = require("react/jsx-runtime");
 function Todo(prop) {
-    return (0, _a.jsx)("div", { children: prop.key.toString() + prop.todo });
+    return (0, jsx_runtime_1.jsx)("div", { children: prop.key.toString() + prop.todo });
 }
 function TodoList(_a) {
     var todos = _a.todos;
-    return (0, _b.jsxs)("div", { children: __spreadArray([], (0, _a.jsx)(Todo, { todo: todos[0].todo }, todos[0].id), true) });
+    return (0, jsx_runtime_1.jsxs)("div", { children: __spreadArray([], (0, jsx_runtime_1.jsx)(Todo, { todo: todos[0].todo }, todos[0].id), true) });
 }
 function TodoListNoError(_a) {
     var todos = _a.todos;
     // any is not checked
-    return (0, _b.jsxs)("div", { children: __spreadArray([], (0, _a.jsx)(Todo, { todo: todos[0].todo }, todos[0].id), true) });
+    return (0, jsx_runtime_1.jsxs)("div", { children: __spreadArray([], (0, jsx_runtime_1.jsx)(Todo, { todo: todos[0].todo }, todos[0].id), true) });
 }
 var x;
-(0, _a.jsx)(TodoList, __assign({}, x));
+(0, jsx_runtime_1.jsx)(TodoList, __assign({}, x));
diff --git a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).symbols b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).symbols
index 5e41936f306..c3be731e55e 100644
--- a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).symbols
+++ b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).symbols
@@ -38,7 +38,6 @@ function Todo(prop: { key: number, todo: string }) {
 >todo : Symbol(todo, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 34))
 
     return <div>{prop.key.toString() + prop.todo}</div>;
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 >prop.key.toString : Symbol(Number.toString, Decl(lib.es5.d.ts, --, --))
 >prop.key : Symbol(key, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 21))
 >prop : Symbol(prop, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 14))
@@ -47,7 +46,6 @@ function Todo(prop: { key: number, todo: string }) {
 >prop.todo : Symbol(todo, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 34))
 >prop : Symbol(prop, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 14))
 >todo : Symbol(todo, Decl(tsxSpreadChildrenInvalidType.tsx, 15, 34))
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 }
 function TodoList({ todos }: TodoListProps) {
 >TodoList : Symbol(TodoList, Decl(tsxSpreadChildrenInvalidType.tsx, 17, 1))
@@ -55,8 +53,6 @@ function TodoList({ todos }: TodoListProps) {
 >TodoListProps : Symbol(TodoListProps, Decl(tsxSpreadChildrenInvalidType.tsx, 11, 1))
 
     return <div>
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
-
         {...<Todo key={todos[0].id} todo={todos[0].todo} />}
 >Todo : Symbol(Todo, Decl(tsxSpreadChildrenInvalidType.tsx, 14, 1))
 >key : Symbol(key, Decl(tsxSpreadChildrenInvalidType.tsx, 20, 17))
@@ -69,7 +65,6 @@ function TodoList({ todos }: TodoListProps) {
 >todo : Symbol(TodoProp.todo, Decl(tsxSpreadChildrenInvalidType.tsx, 9, 15))
 
     </div>;
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 }
 function TodoListNoError({ todos }: TodoListProps) {
 >TodoListNoError : Symbol(TodoListNoError, Decl(tsxSpreadChildrenInvalidType.tsx, 22, 1))
@@ -78,8 +73,6 @@ function TodoListNoError({ todos }: TodoListProps) {
 
     // any is not checked
     return <div>
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
-
         {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}
 >Todo : Symbol(Todo, Decl(tsxSpreadChildrenInvalidType.tsx, 14, 1))
 >key : Symbol(key, Decl(tsxSpreadChildrenInvalidType.tsx, 26, 18))
@@ -92,7 +85,6 @@ function TodoListNoError({ todos }: TodoListProps) {
 >todo : Symbol(TodoProp.todo, Decl(tsxSpreadChildrenInvalidType.tsx, 9, 15))
 
     </div>;
->div : Symbol(JSX.IntrinsicElements, Decl(tsxSpreadChildrenInvalidType.tsx, 1, 22))
 }
 let x: TodoListProps;
 >x : Symbol(x, Decl(tsxSpreadChildrenInvalidType.tsx, 29, 3))
diff --git a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).types b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).types
index b8eb0487037..542fa2c7fca 100644
--- a/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).types
+++ b/tests/baselines/reference/tsxSpreadChildrenInvalidType(jsx=react-jsx,target=es5).types
@@ -21,13 +21,13 @@ interface TodoListProps {
 >todos : TodoProp[]
 }
 function Todo(prop: { key: number, todo: string }) {
->Todo : (prop: {    key: number;    todo: string;}) => JSX.Element
+>Todo : (prop: {    key: number;    todo: string;}) => any
 >prop : { key: number; todo: string; }
 >key : number
 >todo : string
 
     return <div>{prop.key.toString() + prop.todo}</div>;
-><div>{prop.key.toString() + prop.todo}</div> : JSX.Element
+><div>{prop.key.toString() + prop.todo}</div> : any
 >div : any
 >prop.key.toString() + prop.todo : string
 >prop.key.toString() : string
@@ -42,16 +42,16 @@ function Todo(prop: { key: number, todo: string }) {
 >div : any
 }
 function TodoList({ todos }: TodoListProps) {
->TodoList : ({ todos }: TodoListProps) => JSX.Element
+>TodoList : ({ todos }: TodoListProps) => any
 >todos : TodoProp[]
 
     return <div>
-><div>        {...<Todo key={todos[0].id} todo={todos[0].todo} />}    </div> : JSX.Element
+><div>        {...<Todo key={todos[0].id} todo={todos[0].todo} />}    </div> : any
 >div : any
 
         {...<Todo key={todos[0].id} todo={todos[0].todo} />}
-><Todo key={todos[0].id} todo={todos[0].todo} /> : JSX.Element
->Todo : (prop: { key: number; todo: string; }) => JSX.Element
+><Todo key={todos[0].id} todo={todos[0].todo} /> : any
+>Todo : (prop: { key: number; todo: string; }) => any
 >key : number
 >todos[0].id : number
 >todos[0] : TodoProp
@@ -69,19 +69,19 @@ function TodoList({ todos }: TodoListProps) {
 >div : any
 }
 function TodoListNoError({ todos }: TodoListProps) {
->TodoListNoError : ({ todos }: TodoListProps) => JSX.Element
+>TodoListNoError : ({ todos }: TodoListProps) => any
 >todos : TodoProp[]
 
     // any is not checked
     return <div>
-><div>        {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}    </div> : JSX.Element
+><div>        {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}    </div> : any
 >div : any
 
         {...(<Todo key={todos[0].id} todo={todos[0].todo} /> as any)}
 >(<Todo key={todos[0].id} todo={todos[0].todo} /> as any) : any
 ><Todo key={todos[0].id} todo={todos[0].todo} /> as any : any
-><Todo key={todos[0].id} todo={todos[0].todo} /> : JSX.Element
->Todo : (prop: { key: number; todo: string; }) => JSX.Element
+><Todo key={todos[0].id} todo={todos[0].todo} /> : any
+>Todo : (prop: { key: number; todo: string; }) => any
 >key : number
 >todos[0].id : number
 >todos[0] : TodoProp
@@ -102,7 +102,7 @@ let x: TodoListProps;
 >x : TodoListProps
 
     <TodoList {...x}/>
-><TodoList {...x}/> : JSX.Element
->TodoList : ({ todos }: TodoListProps) => JSX.Element
+><TodoList {...x}/> : any
+>TodoList : ({ todos }: TodoListProps) => any
 >x : TodoListProps
 
diff --git a/tests/cases/compiler/APISample_watcher.ts b/tests/cases/compiler/APISample_watcher.ts
index 8b46979e092..dfae23488c6 100644
--- a/tests/cases/compiler/APISample_watcher.ts
+++ b/tests/cases/compiler/APISample_watcher.ts
@@ -51,6 +51,8 @@ function watch(rootFileNames: string[], options: ts.CompilerOptions) {
         getCurrentDirectory: () => process.cwd(),
         getCompilationSettings: () => options,
         getDefaultLibFileName: (options) => ts.getDefaultLibFilePath(options),
+        fileExists: fileName => fs.existsSync(fileName),
+        readFile: fileName => fs.readFileSync(fileName),
     };
 
     // Create the language service files
diff --git a/tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx b/tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx
index 64e3f2b77f6..6830cf4fdcb 100644
--- a/tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx
+++ b/tests/cases/compiler/commentsOnJSXExpressionsArePreserved.tsx
@@ -1,5 +1,6 @@
 // @module: system,commonjs
 // @jsx: react,react-jsx,react-jsxdev,preserve
+// @moduleDetection: legacy,auto,force
 // file is intentionally not a module - this tests for a crash in the module/system transforms alongside the `react-jsx` and `react-jsxdev` outputs
 namespace JSX {}
 class Component {