fix 'fileExists' check by using stat directly

vladima · vladima · commit 354e650341ad · 2016-02-11T16:59:54.000-08:00
diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
@@ -411,7 +411,7 @@ namespace ts {
             const useCaseSensitiveFileNames = platform !== "win32" && platform !== "win64" && platform !== "darwin";
 
             function readFile(fileName: string, encoding?: string): string {
-                if (!_fs.existsSync(fileName)) {
+                if (!fileExists(fileName)) {
                     return undefined;
                 }
                 const buffer = _fs.readFileSync(fileName);
@@ -462,6 +462,31 @@ namespace ts {
                 return useCaseSensitiveFileNames ? path : path.toLowerCase();
             }
 
+            const enum FileSystemEntryKind {
+                File,
+                Directory
+            }
+            function fileSystemEntryExists(path: string, entryKind: FileSystemEntryKind): boolean {
+                try {
+                    const stat = _fs.statSync(path);
+                    switch (entryKind) {
+                        case FileSystemEntryKind.File: return stat.isFile();
+                        case FileSystemEntryKind.Directory: return stat.isDirectory();
+                    }
+                }
+                catch (e) {
+                    return false;
+                }
+            }
+
+            function fileExists(path: string): boolean {
+                return fileSystemEntryExists(path, FileSystemEntryKind.File);
+            }
+
+            function directoryExists(path: string): boolean {
+                return fileSystemEntryExists(path, FileSystemEntryKind.Directory);
+            }
+
             function readDirectory(path: string, extension?: string, exclude?: string[]): string[] {
                 const result: string[] = [];
                 exclude = map(exclude, s => getCanonicalPath(combinePaths(path, s)));
@@ -538,12 +563,8 @@ namespace ts {
                 resolvePath: function (path: string): string {
                     return _path.resolve(path);
                 },
-                fileExists(path: string): boolean {
-                    return _fs.existsSync(path);
-                },
-                directoryExists(path: string) {
-                    return _fs.existsSync(path) && _fs.statSync(path).isDirectory();
-                },
+                fileExists,
+                directoryExists,
                 createDirectory(directoryName: string) {
                     if (!this.directoryExists(directoryName)) {
                         _fs.mkdirSync(directoryName);
