Ensure that file watcher is closed only once for affected file locations that share watcher because of different names but same real path (microsoft#50150)

* Add test where clearing affected files watcher that also is shared by real path causes Debug failure

* Ensure that file watcher is closed only once for affected file locations that share watcher because of different names but same real path

* Lift up package json map

Author: sheetalkamat

src/compiler/resolutionCache.ts

@@ -360,8 +360,6 @@ namespace ts {
                 if (watcher.files === 0 && watcher.resolutions === 0) {
                     fileWatchesOfAffectingLocations.delete(path);
                     watcher.watcher.close();
-                    // Ensure when watching symlinked package.json, we can close the actual file watcher only once
-                    watcher.watcher = noopFileWatcher;
                 }
             });
 
@@ -771,17 +769,25 @@ namespace ts {
             }
             const paths = new Set<string>();
             paths.add(locationToWatch);
+            let actualWatcher = canWatchDirectoryOrFile(resolutionHost.toPath(locationToWatch)) ?
+                resolutionHost.watchAffectingFileLocation(locationToWatch, (fileName, eventKind) => {
+                    cachedDirectoryStructureHost?.addOrDeleteFile(fileName, resolutionHost.toPath(locationToWatch), eventKind);
+                    const packageJsonMap = moduleResolutionCache.getPackageJsonInfoCache().getInternalMap();
+                    paths.forEach(path => {
+                        if (watcher.resolutions) (affectingPathChecks ??= new Set()).add(path);
+                        if (watcher.files) (affectingPathChecksForFile ??= new Set()).add(path);
+                        packageJsonMap?.delete(resolutionHost.toPath(path));
+                    });
+                    resolutionHost.scheduleInvalidateResolutionsOfFailedLookupLocations();
+                }) : noopFileWatcher;
             const watcher: FileWatcherOfAffectingLocation = {
-                watcher: canWatchDirectoryOrFile(resolutionHost.toPath(locationToWatch)) ?
-                    resolutionHost.watchAffectingFileLocation(locationToWatch, (fileName, eventKind) => {
-                        cachedDirectoryStructureHost?.addOrDeleteFile(fileName, resolutionHost.toPath(locationToWatch), eventKind);
-                        paths.forEach(path => {
-                            if (watcher.resolutions) (affectingPathChecks ??= new Set()).add(path);
-                            if (watcher.files) (affectingPathChecksForFile ??= new Set()).add(path);
-                            moduleResolutionCache.getPackageJsonInfoCache().getInternalMap()?.delete(resolutionHost.toPath(path));
-                        });
-                        resolutionHost.scheduleInvalidateResolutionsOfFailedLookupLocations();
-                    }) : noopFileWatcher,
+                watcher: actualWatcher !== noopFileWatcher ? {
+                    close: () => {
+                        actualWatcher.close();
+                        // Ensure when watching symlinked package.json, we can close the actual file watcher only once
+                        actualWatcher = noopFileWatcher;
+                    }
+                } : actualWatcher,
                 resolutions: forResolution ? 1 : 0,
                 files: forResolution ? 0 : 1,
                 paths,

src/harness/virtualFileSystemWithWatch.ts

@@ -116,7 +116,14 @@ interface Array<T> { length: number; [n: number]: T; }`
 
     function createWatcher<T>(map: MultiMap<Path, T>, path: Path, callback: T): FileWatcher {
         map.add(path, callback);
-        return { close: () => map.remove(path, callback) };
+        let closed = false;
+        return {
+            close: () => {
+                Debug.assert(!closed);
+                map.remove(path, callback);
+                closed = true;
+            }
+        };
     }
 
     export function getDiffInKeys<T>(map: ESMap<string, T>, expectedKeys: readonly string[]) {

src/testRunner/unittests/tsserver/symLinks.ts

@@ -131,6 +131,16 @@ new C();`
                         host.runQueuedTimeoutCallbacks(); // Actual update
 
                         verifyGetErrRequest({ session, host, files: [recognizersDateTimeSrcFile] });
+
+                        // Change config file's module resolution affecting option
+                        const config = JSON.parse(host.readFile(recognizerDateTimeTsconfigPath)!);
+                        host.writeFile(recognizerDateTimeTsconfigPath, JSON.stringify({
+                            ...config,
+                            compilerOptions: { ...config.compilerOptions, resolveJsonModule: true }
+                        }));
+                        host.runQueuedTimeoutCallbacks(); // Scheduled invalidation of resolutions
+                        host.runQueuedTimeoutCallbacks(); // Actual update
+
                         baselineTsserverLogs("symLinks", `module resolution${withPathMapping ? " with path mapping" : ""} when project compiles from sources`, session);
                     });