From 983250fefc38dcc7cab7a22905bde138820c6029 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 10 Nov 2025 16:49:56 +0000
Subject: [PATCH] Fix error message to show 'Fragment' instead of 'React' for
 react-jsx modes

Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>
---
 src/compiler/checker.ts                       |  6 ++-
 ...FactoryReference(jsx=react-jsx).errors.txt |  4 +-
 ...toryReference(jsx=react-jsxdev).errors.txt |  4 +-
 ...formCustomImport(jsx=react-jsx).errors.txt |  4 +-
 ...mCustomImport(jsx=react-jsxdev).errors.txt |  4 +-
 ...stomImportPragma(jsx=react-jsx).errors.txt |  4 +-
 ...mImportPragma(jsx=react-jsxdev).errors.txt |  4 +-
 ...jsxRuntimePragma(jsx=react-jsx).errors.txt | 41 +++++++++++++++++++
 ...RuntimePragma(jsx=react-jsxdev).errors.txt | 41 +++++++++++++++++++
 9 files changed, 99 insertions(+), 13 deletions(-)
 create mode 100644 tests/baselines/reference/jsxRuntimePragma(jsx=react-jsx).errors.txt
 create mode 100644 tests/baselines/reference/jsxRuntimePragma(jsx=react-jsxdev).errors.txt

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index f3cf9c10ff3..2e9751bf24a 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -37441,11 +37441,15 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         if (!shouldResolveFactoryReference) return sourceFileLinks.jsxFragmentType = anyType;
 
         const shouldModuleRefErr = compilerOptions.jsx !== JsxEmit.Preserve && compilerOptions.jsx !== JsxEmit.ReactNative;
+        // When using react-jsx/react-jsxdev, the fragment comes from the jsx-runtime module as "Fragment" export
+        // Use "Fragment" in error message instead of the default "React" namespace
+        const isModernJsx = compilerOptions.jsx === JsxEmit.ReactJSX || compilerOptions.jsx === JsxEmit.ReactJSXDev;
+        const fragmentFactoryNameForError = isModernJsx ? ReactNames.Fragment : jsxFragmentFactoryName;
         const jsxFactoryRefErr = diagnostics ? Diagnostics.Using_JSX_fragments_requires_fragment_factory_0_to_be_in_scope_but_it_could_not_be_found : undefined;
         const jsxFactorySymbol = getJsxNamespaceContainerForImplicitImport(node) ??
             resolveName(
                 node,
-                jsxFragmentFactoryName,
+                fragmentFactoryNameForError,
                 shouldModuleRefErr ? SymbolFlags.Value : SymbolFlags.Value & ~SymbolFlags.Enum,
                 /*nameNotFoundMessage*/ jsxFactoryRefErr,
                 /*isUse*/ true,
diff --git a/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsx).errors.txt b/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsx).errors.txt
index c8caaefa362..97b1dd60a77 100644
--- a/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsx).errors.txt
+++ b/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsx).errors.txt
@@ -1,5 +1,5 @@
 jsxFragmentFactoryReference.tsx(3,9): error TS2875: This JSX tag requires the module path 'react/jsx-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
-jsxFragmentFactoryReference.tsx(3,9): error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+jsxFragmentFactoryReference.tsx(3,9): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
 
 
 ==== jsxFragmentFactoryReference.tsx (2 errors) ====
@@ -9,7 +9,7 @@ jsxFragmentFactoryReference.tsx(3,9): error TS2879: Using JSX fragments requires
             ~~
 !!! error TS2875: This JSX tag requires the module path 'react/jsx-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
             ~~
-!!! error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
         )
     }
     
\ No newline at end of file
diff --git a/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsxdev).errors.txt b/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsxdev).errors.txt
index 16bb6f5a544..400aa3bd175 100644
--- a/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsxdev).errors.txt
+++ b/tests/baselines/reference/jsxFragmentFactoryReference(jsx=react-jsxdev).errors.txt
@@ -1,5 +1,5 @@
 jsxFragmentFactoryReference.tsx(3,9): error TS2875: This JSX tag requires the module path 'react/jsx-dev-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
-jsxFragmentFactoryReference.tsx(3,9): error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+jsxFragmentFactoryReference.tsx(3,9): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
 
 
 ==== jsxFragmentFactoryReference.tsx (2 errors) ====
@@ -9,7 +9,7 @@ jsxFragmentFactoryReference.tsx(3,9): error TS2879: Using JSX fragments requires
             ~~
 !!! error TS2875: This JSX tag requires the module path 'react/jsx-dev-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
             ~~
-!!! error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
         )
     }
     
\ No newline at end of file
diff --git a/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsx).errors.txt b/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsx).errors.txt
index 2b8fbaf4e46..2b1ec10df02 100644
--- a/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsx).errors.txt
+++ b/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsx).errors.txt
@@ -1,5 +1,5 @@
 jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2875: This JSX tag requires the module path 'preact/jsx-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
-jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
 
 
 ==== jsxJsxsCjsTransformCustomImport.tsx (2 errors) ====
@@ -8,7 +8,7 @@ jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2879: Using JSX fragments req
               ~~
 !!! error TS2875: This JSX tag requires the module path 'preact/jsx-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
               ~~
-!!! error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
       <p></p>
       text
       <div className="foo"></div>
diff --git a/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsxdev).errors.txt b/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsxdev).errors.txt
index 31af5093deb..062df44ff80 100644
--- a/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsxdev).errors.txt
+++ b/tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsxdev).errors.txt
@@ -1,5 +1,5 @@
 jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2875: This JSX tag requires the module path 'preact/jsx-dev-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
-jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
 
 
 ==== jsxJsxsCjsTransformCustomImport.tsx (2 errors) ====
@@ -8,7 +8,7 @@ jsxJsxsCjsTransformCustomImport.tsx(2,11): error TS2879: Using JSX fragments req
               ~~
 !!! error TS2875: This JSX tag requires the module path 'preact/jsx-dev-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
               ~~
-!!! error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
       <p></p>
       text
       <div className="foo"></div>
diff --git a/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsx).errors.txt b/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsx).errors.txt
index 7155c43a5da..61276f782e4 100644
--- a/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsx).errors.txt
+++ b/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsx).errors.txt
@@ -1,5 +1,5 @@
 preact.tsx(3,11): error TS2875: This JSX tag requires the module path 'preact/jsx-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
-preact.tsx(3,11): error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+preact.tsx(3,11): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
 
 
 ==== react.tsx (0 errors) ====
@@ -20,7 +20,7 @@ preact.tsx(3,11): error TS2879: Using JSX fragments requires fragment factory 'R
               ~~
 !!! error TS2875: This JSX tag requires the module path 'preact/jsx-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
               ~~
-!!! error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
       <p></p>
       text
       <div className="foo"></div>
diff --git a/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsxdev).errors.txt b/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsxdev).errors.txt
index ad4bb3c20b1..3a1dfd23eb3 100644
--- a/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsxdev).errors.txt
+++ b/tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsxdev).errors.txt
@@ -1,5 +1,5 @@
 preact.tsx(3,11): error TS2875: This JSX tag requires the module path 'preact/jsx-dev-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
-preact.tsx(3,11): error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+preact.tsx(3,11): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
 
 
 ==== react.tsx (0 errors) ====
@@ -20,7 +20,7 @@ preact.tsx(3,11): error TS2879: Using JSX fragments requires fragment factory 'R
               ~~
 !!! error TS2875: This JSX tag requires the module path 'preact/jsx-dev-runtime' to exist, but none could be found. Make sure you have types for the appropriate package installed.
               ~~
-!!! error TS2879: Using JSX fragments requires fragment factory 'React' to be in scope, but it could not be found.
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
       <p></p>
       text
       <div className="foo"></div>
diff --git a/tests/baselines/reference/jsxRuntimePragma(jsx=react-jsx).errors.txt b/tests/baselines/reference/jsxRuntimePragma(jsx=react-jsx).errors.txt
new file mode 100644
index 00000000000..988e3e9d679
--- /dev/null
+++ b/tests/baselines/reference/jsxRuntimePragma(jsx=react-jsx).errors.txt
@@ -0,0 +1,41 @@
+four.tsx(6,21): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+one.tsx(5,21): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+
+
+==== one.tsx (1 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime classic */
+    import * as React from "react";
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+                        ~~
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+    export const selfClosing = <img src="./image.png" />;
+==== two.tsx (0 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime automatic */
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+    export const selfClosing = <img src="./image.png" />;
+==== three.tsx (0 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime classic */
+    /* @jsxRuntime automatic */
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+    export const selfClosing = <img src="./image.png" />;
+==== four.tsx (1 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime automatic */
+    /* @jsxRuntime classic */
+    import * as React from "react";
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+                        ~~
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+    export const selfClosing = <img src="./image.png" />;
+==== index.ts (0 errors) ====
+    export * as one from "./one.js";
+    export * as two from "./two.js";
+    export * as three from "./three.js";
+    export * as four from "./four.js";
\ No newline at end of file
diff --git a/tests/baselines/reference/jsxRuntimePragma(jsx=react-jsxdev).errors.txt b/tests/baselines/reference/jsxRuntimePragma(jsx=react-jsxdev).errors.txt
new file mode 100644
index 00000000000..988e3e9d679
--- /dev/null
+++ b/tests/baselines/reference/jsxRuntimePragma(jsx=react-jsxdev).errors.txt
@@ -0,0 +1,41 @@
+four.tsx(6,21): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+one.tsx(5,21): error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+
+
+==== one.tsx (1 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime classic */
+    import * as React from "react";
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+                        ~~
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+    export const selfClosing = <img src="./image.png" />;
+==== two.tsx (0 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime automatic */
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+    export const selfClosing = <img src="./image.png" />;
+==== three.tsx (0 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime classic */
+    /* @jsxRuntime automatic */
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+    export const selfClosing = <img src="./image.png" />;
+==== four.tsx (1 errors) ====
+    /// <reference path="/.lib/react16.d.ts" />
+    /* @jsxRuntime automatic */
+    /* @jsxRuntime classic */
+    import * as React from "react";
+    export const HelloWorld = () => <h1>Hello world</h1>;
+    export const frag = <><div></div></>;
+                        ~~
+!!! error TS2879: Using JSX fragments requires fragment factory 'Fragment' to be in scope, but it could not be found.
+    export const selfClosing = <img src="./image.png" />;
+==== index.ts (0 errors) ====
+    export * as one from "./one.js";
+    export * as two from "./two.js";
+    export * as three from "./three.js";
+    export * as four from "./four.js";
\ No newline at end of file