From 6bde4b5c02e1ab44517f3ff2ca1387654c72be05 Mon Sep 17 00:00:00 2001
From: Sheetal Nandi <shkamat@microsoft.com>
Date: Thu, 29 Oct 2020 12:18:43 -0700
Subject: [PATCH] Fix missing file name of extended source file in
 synchronizeProjectList when it is missing on disk (#41222)

Fixes #40136
---
 src/compiler/commandLineParser.ts             |  2 +-
 src/testRunner/unittests/tsserver/projects.ts | 42 +++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 117410246d9..56cc83516e5 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -1578,7 +1578,7 @@ namespace ts {
      */
     export function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile {
         const textOrDiagnostic = tryReadFile(fileName, readFile);
-        return isString(textOrDiagnostic) ? parseJsonText(fileName, textOrDiagnostic) : <TsConfigSourceFile>{ parseDiagnostics: [textOrDiagnostic] };
+        return isString(textOrDiagnostic) ? parseJsonText(fileName, textOrDiagnostic) : <TsConfigSourceFile>{ fileName, parseDiagnostics: [textOrDiagnostic] };
     }
 
     /*@internal*/
diff --git a/src/testRunner/unittests/tsserver/projects.ts b/src/testRunner/unittests/tsserver/projects.ts
index 2de2da67af3..0afe37c4639 100644
--- a/src/testRunner/unittests/tsserver/projects.ts
+++ b/src/testRunner/unittests/tsserver/projects.ts
@@ -1481,6 +1481,48 @@ namespace ts.projectSystem {
             ]);
         });
 
+        it("synchronizeProjectList returns correct information when base configuration file cannot be resolved", () => {
+            const file: File = {
+                path: `${tscWatch.projectRoot}/index.ts`,
+                content: "export const foo = 5;"
+            };
+            const config: File = {
+                path: `${tscWatch.projectRoot}/tsconfig.json`,
+                content: JSON.stringify({ extends: "./tsconfig_base.json" })
+            };
+            const host = createServerHost([file, config, libFile]);
+            const projectService = createProjectService(host);
+            projectService.openClientFile(file.path);
+            const knownProjects = projectService.synchronizeProjectList([], /*includeProjectReferenceRedirectInfo*/ false);
+            assert.deepEqual(knownProjects[0].files, [
+                libFile.path,
+                file.path,
+                config.path,
+                `${tscWatch.projectRoot}/tsconfig_base.json`,
+            ]);
+        });
+
+        it("synchronizeProjectList returns correct information when base configuration file cannot be resolved and redirect info is requested", () => {
+            const file: File = {
+                path: `${tscWatch.projectRoot}/index.ts`,
+                content: "export const foo = 5;"
+            };
+            const config: File = {
+                path: `${tscWatch.projectRoot}/tsconfig.json`,
+                content: JSON.stringify({ extends: "./tsconfig_base.json" })
+            };
+            const host = createServerHost([file, config, libFile]);
+            const projectService = createProjectService(host);
+            projectService.openClientFile(file.path);
+            const knownProjects = projectService.synchronizeProjectList([], /*includeProjectReferenceRedirectInfo*/ true);
+            assert.deepEqual(knownProjects[0].files, [
+                { fileName: libFile.path, isSourceOfProjectReferenceRedirect: false },
+                { fileName: file.path, isSourceOfProjectReferenceRedirect: false },
+                { fileName: config.path, isSourceOfProjectReferenceRedirect: false },
+                { fileName: `${tscWatch.projectRoot}/tsconfig_base.json`, isSourceOfProjectReferenceRedirect: false },
+            ]);
+        });
+
         it("handles delayed directory watch invoke on file creation", () => {
             const projectRootPath = "/users/username/projects/project";
             const fileB: File = {