Ignore anything starting with ".git"

Fixes microsoft#29782

Author: sheetalkamat

src/compiler/resolutionCache.ts

@@ -71,8 +71,8 @@ namespace ts {
         nonRecursive?: boolean;
     }
 
-    export function isPathInNodeModulesStartingWithDot(path: Path) {
-        return stringContains(path, "/node_modules/.");
+    export function isPathIgnored(path: Path) {
+        return some(ignoredPaths, searchPath => stringContains(path, searchPath));
     }
 
     export const maxNumberOfFilesToIterateForInvalidation = 256;
@@ -696,7 +696,7 @@ namespace ts {
             }
             else {
                 // If something to do with folder/file starting with "." in node_modules folder, skip it
-                if (isPathInNodeModulesStartingWithDot(fileOrDirectoryPath)) return false;
+                if (isPathIgnored(fileOrDirectoryPath)) return false;
 
                 // Some file or directory in the watching directory is created
                 // Return early if it does not have any of the watching extension or not the custom failed lookup path

src/compiler/sys.ts

@@ -326,6 +326,9 @@ namespace ts {
                 : FileWatcherEventKind.Changed;
     }
 
+    /*@internal*/
+    export const ignoredPaths = ["/node_modules/.", "/.git"];
+
     /*@internal*/
     export interface RecursiveDirectoryWatcherHost {
         watchDirectory: HostWatchDirectory;
@@ -371,7 +374,7 @@ namespace ts {
             else {
                 directoryWatcher = {
                     watcher: host.watchDirectory(dirName, fileName => {
-                        if (isInNodeModulesStartingWithDot(fileName)) return;
+                        if (isIgnoredPath(fileName)) return;
 
                         // Call the actual callback
                         callbackCache.forEach((callbacks, rootDirName) => {
@@ -428,7 +431,7 @@ namespace ts {
                     const childFullName = getNormalizedAbsolutePath(child, parentDir);
                     // Filter our the symbolic link directories since those arent included in recursive watch
                     // which is same behaviour when recursive: true is passed to fs.watch
-                    return !isInNodeModulesStartingWithDot(childFullName) && filePathComparer(childFullName, normalizePath(host.realpath(childFullName))) === Comparison.EqualTo ? childFullName : undefined;
+                    return !isIgnoredPath(childFullName) && filePathComparer(childFullName, normalizePath(host.realpath(childFullName))) === Comparison.EqualTo ? childFullName : undefined;
                 }) : emptyArray,
                 existingChildWatches,
                 (child, childWatcher) => filePathComparer(child, childWatcher.dirName),
@@ -455,8 +458,8 @@ namespace ts {
             }
         }
 
-        function isInNodeModulesStartingWithDot(path: string) {
-            return isInPath(path, "/node_modules/.");
+        function isIgnoredPath(path: string) {
+            return some(ignoredPaths, searchPath => isInPath(path, searchPath));
         }
 
         function isInPath(path: string, searchPath: string) {

src/compiler/watch.ts

@@ -987,7 +987,7 @@ namespace ts {
                     }
                     nextSourceFileVersion(fileOrDirectoryPath);
 
-                    if (isPathInNodeModulesStartingWithDot(fileOrDirectoryPath)) return;
+                    if (isPathIgnored(fileOrDirectoryPath)) return;
 
                     // If the the added or created file or directory is not supported file name, ignore the file
                     // But when watched directory is added/removed, we need to reload the file list

src/server/editorServices.ts

@@ -1002,7 +1002,7 @@ namespace ts.server {
                 fileOrDirectory => {
                     const fileOrDirectoryPath = this.toPath(fileOrDirectory);
                     project.getCachedDirectoryStructureHost().addOrDeleteFileOrDirectory(fileOrDirectory, fileOrDirectoryPath);
-                    if (isPathInNodeModulesStartingWithDot(fileOrDirectoryPath)) return;
+                    if (isPathIgnored(fileOrDirectoryPath)) return;
                     const configFilename = project.getConfigFilePath();
 
                     // If the the added or created file or directory is not supported file name, ignore the file
@@ -2071,7 +2071,7 @@ namespace ts.server {
                 watchDir,
                 (fileOrDirectory) => {
                     const fileOrDirectoryPath = this.toPath(fileOrDirectory);
-                    if (isPathInNodeModulesStartingWithDot(fileOrDirectoryPath)) return;
+                    if (isPathIgnored(fileOrDirectoryPath)) return;
 
                     // Has extension
                     Debug.assert(result.refCount > 0);

src/testRunner/unittests/tsserver/watchEnvironment.ts

@@ -183,6 +183,22 @@ namespace ts.projectSystem {
         host.checkTimeoutQueueLength(0);
         verifyProject();
 
+        const gitIgnoredFileFromIgnoreDirectory: File = {
+            path: `${projectFolder}/.git/someFile.d.ts`,
+            content: ""
+        };
+        host.ensureFileOrFolder(gitIgnoredFileFromIgnoreDirectory);
+        host.checkTimeoutQueueLength(0);
+        verifyProject();
+
+        const gitIgnoredFile: File = {
+            path: `${projectFolder}/.gitCache.d.ts`,
+            content: ""
+        };
+        host.ensureFileOrFolder(gitIgnoredFile);
+        host.checkTimeoutQueueLength(0);
+        verifyProject();
+
         function verifyProject() {
             checkWatchedDirectories(host, emptyArray, /*recursive*/ true);
             checkWatchedFilesDetailed(host, expectedWatchedFiles);