From e67574446a56bbf5ceb8a3fd8f416ad8ca0c2907 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Wed, 9 Dec 2015 16:21:04 -0800
Subject: [PATCH 01/28] Fix too many watcher instances issue

---
 src/compiler/sys.ts | 59 ++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 50 insertions(+), 9 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index cd7580119b5..5482e549ebf 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -24,7 +24,7 @@ namespace ts {
     interface WatchedFile {
         fileName: string;
         callback: (fileName: string, removed?: boolean) => void;
-        mtime: Date;
+        mtime?: Date;
     }
 
     export interface FileWatcher {
@@ -218,7 +218,7 @@ namespace ts {
 
             // average async stat takes about 30 microseconds
             // set chunk size to do 30 files in < 1 millisecond
-            function createWatchedFileSet(interval = 2500, chunkSize = 30) {
+            function createPollingWatchedFileSet(interval = 2500, chunkSize = 30) {
                 let watchedFiles: WatchedFile[] = [];
                 let nextFileToCheck = 0;
                 let watchTimer: any;
@@ -293,6 +293,50 @@ namespace ts {
                     removeFile: removeFile
                 };
             }
+            
+            function createWatchedFileSet() {
+                let watchedDirectories: { [path: string]: FileWatcher } = {};
+                let watchedFiles: { [fileName: string]: (fileName: string, removed?: boolean) => void; } = {};
+                
+                function addFile(fileName: string, callback: (fileName: string, removed?: boolean) => void): WatchedFile {
+                    const file: WatchedFile = { fileName, callback };
+                    let watchedPaths = Object.keys(watchedDirectories);
+                    // Try to find parent paths that are already watched. If found, don't add directory watchers
+                    let watchedParentPaths = watchedPaths.filter(path => fileName.indexOf(path) === 0);
+                    // If adding new watchers, try to find children paths that are already watched. If found, close them. 
+                    if (watchedParentPaths.length === 0) {
+                        let pathToWatch = ts.getDirectoryPath(fileName);
+                        for (let watchedPath in watchedDirectories) {
+                            if (watchedPath.indexOf(pathToWatch) === 0) {
+                                watchedDirectories[watchedPath].close();
+                                delete watchedDirectories[watchedPath];
+                            }
+                        }
+                        watchedDirectories[pathToWatch] = _fs.watch(
+                            pathToWatch, 
+                            (eventName: string, relativeFileName: string) => fileEventHandler(eventName, ts.normalizePath(ts.combinePaths(pathToWatch, relativeFileName)))
+                        );
+                    }
+                    watchedFiles[fileName] = callback;
+                    return { fileName, callback }
+                }
+                
+                function removeFile(file: WatchedFile) {
+                    delete watchedFiles[file.fileName];
+                }
+                
+                function fileEventHandler(eventName: string, fileName: string) {
+                    if (watchedFiles[fileName]) {
+                        let callback = watchedFiles[fileName];
+                        callback(fileName);
+                    }
+                }
+                
+                return {
+                    addFile: addFile,
+                    removeFile: removeFile
+                }
+            }
 
             // REVIEW: for now this implementation uses polling.
             // The advantage of polling is that it works reliably
@@ -307,6 +351,7 @@ namespace ts {
             // changes for large reference sets? If so, do we want
             // to increase the chunk size or decrease the interval
             // time dynamically to match the large reference set?
+            const pollingWatchedFileSet = createPollingWatchedFileSet();
             const watchedFileSet = createWatchedFileSet();
 
             function isNode4OrLater(): Boolean {
@@ -411,14 +456,10 @@ namespace ts {
                     // and is more efficient than `fs.watchFile` (ref: https://github.com/nodejs/node/pull/2649
                     // and https://github.com/Microsoft/TypeScript/issues/4643), therefore
                     // if the current node.js version is newer than 4, use `fs.watch` instead.
-                    if (isNode4OrLater()) {
-                        // Note: in node the callback of fs.watch is given only the relative file name as a parameter
-                        return _fs.watch(fileName, (eventName: string, relativeFileName: string) => callback(fileName));
-                    }
-
-                    const watchedFile = watchedFileSet.addFile(fileName, callback);
+                    let fileSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
+                    const watchedFile = fileSet.addFile(fileName, callback);
                     return {
-                        close: () => watchedFileSet.removeFile(watchedFile)
+                        close: () => fileSet.removeFile(watchedFile)
                     };
                 },
                 watchDirectory: (path, callback, recursive) => {

From 5fa7bec22688fd81c191abc430ecb7424abf144b Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Thu, 10 Dec 2015 17:52:25 -0800
Subject: [PATCH 02/28] revert back to polling watching for approaching release

---
 src/compiler/sys.ts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 5482e549ebf..0cb0258de3f 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -352,7 +352,7 @@ namespace ts {
             // to increase the chunk size or decrease the interval
             // time dynamically to match the large reference set?
             const pollingWatchedFileSet = createPollingWatchedFileSet();
-            const watchedFileSet = createWatchedFileSet();
+            // const watchedFileSet = createWatchedFileSet();
 
             function isNode4OrLater(): Boolean {
                 return parseInt(process.version.charAt(1)) >= 4;
@@ -456,7 +456,8 @@ namespace ts {
                     // and is more efficient than `fs.watchFile` (ref: https://github.com/nodejs/node/pull/2649
                     // and https://github.com/Microsoft/TypeScript/issues/4643), therefore
                     // if the current node.js version is newer than 4, use `fs.watch` instead.
-                    let fileSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
+                    // let fileSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
+                    let fileSet = pollingWatchedFileSet;
                     const watchedFile = fileSet.addFile(fileName, callback);
                     return {
                         close: () => fileSet.removeFile(watchedFile)

From 36cc0e017b7199e87a7bb1d18580f8380fd42107 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Thu, 10 Dec 2015 17:59:07 -0800
Subject: [PATCH 03/28] fix linter errors

---
 src/compiler/sys.ts | 36 +++++++++++++++++-------------------
 1 file changed, 17 insertions(+), 19 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 0cb0258de3f..cbb7e320780 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -293,49 +293,49 @@ namespace ts {
                     removeFile: removeFile
                 };
             }
-            
+
             function createWatchedFileSet() {
-                let watchedDirectories: { [path: string]: FileWatcher } = {};
-                let watchedFiles: { [fileName: string]: (fileName: string, removed?: boolean) => void; } = {};
-                
+                const watchedDirectories: { [path: string]: FileWatcher } = {};
+                const watchedFiles: { [fileName: string]: (fileName: string, removed?: boolean) => void; } = {};
+
                 function addFile(fileName: string, callback: (fileName: string, removed?: boolean) => void): WatchedFile {
                     const file: WatchedFile = { fileName, callback };
-                    let watchedPaths = Object.keys(watchedDirectories);
+                    const watchedPaths = Object.keys(watchedDirectories);
                     // Try to find parent paths that are already watched. If found, don't add directory watchers
-                    let watchedParentPaths = watchedPaths.filter(path => fileName.indexOf(path) === 0);
+                    const watchedParentPaths = watchedPaths.filter(path => fileName.indexOf(path) === 0);
                     // If adding new watchers, try to find children paths that are already watched. If found, close them. 
                     if (watchedParentPaths.length === 0) {
-                        let pathToWatch = ts.getDirectoryPath(fileName);
-                        for (let watchedPath in watchedDirectories) {
+                        const pathToWatch = ts.getDirectoryPath(fileName);
+                        for (const watchedPath in watchedDirectories) {
                             if (watchedPath.indexOf(pathToWatch) === 0) {
                                 watchedDirectories[watchedPath].close();
                                 delete watchedDirectories[watchedPath];
                             }
                         }
                         watchedDirectories[pathToWatch] = _fs.watch(
-                            pathToWatch, 
+                            pathToWatch,
                             (eventName: string, relativeFileName: string) => fileEventHandler(eventName, ts.normalizePath(ts.combinePaths(pathToWatch, relativeFileName)))
                         );
                     }
                     watchedFiles[fileName] = callback;
-                    return { fileName, callback }
+                    return { fileName, callback };
                 }
-                
+
                 function removeFile(file: WatchedFile) {
                     delete watchedFiles[file.fileName];
                 }
-                
+
                 function fileEventHandler(eventName: string, fileName: string) {
                     if (watchedFiles[fileName]) {
-                        let callback = watchedFiles[fileName];
+                        const callback = watchedFiles[fileName];
                         callback(fileName);
                     }
                 }
-                
+
                 return {
                     addFile: addFile,
                     removeFile: removeFile
-                }
+                };
             }
 
             // REVIEW: for now this implementation uses polling.
@@ -456,11 +456,9 @@ namespace ts {
                     // and is more efficient than `fs.watchFile` (ref: https://github.com/nodejs/node/pull/2649
                     // and https://github.com/Microsoft/TypeScript/issues/4643), therefore
                     // if the current node.js version is newer than 4, use `fs.watch` instead.
-                    // let fileSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
-                    let fileSet = pollingWatchedFileSet;
-                    const watchedFile = fileSet.addFile(fileName, callback);
+                    const watchedFile = pollingWatchedFileSet.addFile(fileName, callback);
                     return {
-                        close: () => fileSet.removeFile(watchedFile)
+                        close: () => pollingWatchedFileSet.removeFile(watchedFile)
                     };
                 },
                 watchDirectory: (path, callback, recursive) => {

From d41901576a7c697e79594fc518dfb0fef6ce4b63 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Tue, 15 Dec 2015 08:39:51 -0800
Subject: [PATCH 04/28] Use FileMap instead of string array

---
 src/compiler/sys.ts | 72 ++++++++++++++++++++++++---------------------
 1 file changed, 39 insertions(+), 33 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index cbb7e320780..91371e62ec8 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -295,47 +295,52 @@ namespace ts {
             }
 
             function createWatchedFileSet() {
-                const watchedDirectories: { [path: string]: FileWatcher } = {};
-                const watchedFiles: { [fileName: string]: (fileName: string, removed?: boolean) => void; } = {};
+                const watchedDirectories = createFileMap<FileWatcher>();
+                const watchedFiles = createFileMap<(fileName: string, removed?: boolean) => void>();
+                const currentDirectory = process.cwd();
+
+                return { addFile, removeFile };
 
                 function addFile(fileName: string, callback: (fileName: string, removed?: boolean) => void): WatchedFile {
-                    const file: WatchedFile = { fileName, callback };
-                    const watchedPaths = Object.keys(watchedDirectories);
-                    // Try to find parent paths that are already watched. If found, don't add directory watchers
-                    const watchedParentPaths = watchedPaths.filter(path => fileName.indexOf(path) === 0);
-                    // If adding new watchers, try to find children paths that are already watched. If found, close them. 
-                    if (watchedParentPaths.length === 0) {
-                        const pathToWatch = ts.getDirectoryPath(fileName);
-                        for (const watchedPath in watchedDirectories) {
-                            if (watchedPath.indexOf(pathToWatch) === 0) {
-                                watchedDirectories[watchedPath].close();
-                                delete watchedDirectories[watchedPath];
-                            }
-                        }
-                        watchedDirectories[pathToWatch] = _fs.watch(
-                            pathToWatch,
-                            (eventName: string, relativeFileName: string) => fileEventHandler(eventName, ts.normalizePath(ts.combinePaths(pathToWatch, relativeFileName)))
-                        );
+                    const path = toPath(fileName, currentDirectory, getCanonicalPath);
+                    const parentDirPath = toPath(ts.getDirectoryPath(fileName), currentDirectory, getCanonicalPath);
+
+                    if (!watchedDirectories.contains(parentDirPath)) {
+                        watchedDirectories.set(parentDirPath, _fs.watch(
+                            parentDirPath,
+                            (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, parentDirPath)
+                        ));
                     }
-                    watchedFiles[fileName] = callback;
+                    watchedFiles.set(path, callback);
                     return { fileName, callback };
                 }
 
                 function removeFile(file: WatchedFile) {
-                    delete watchedFiles[file.fileName];
-                }
+                    const path = toPath(file.fileName, currentDirectory, getCanonicalPath);
+                    watchedFiles.remove(path);
 
-                function fileEventHandler(eventName: string, fileName: string) {
-                    if (watchedFiles[fileName]) {
-                        const callback = watchedFiles[fileName];
-                        callback(fileName);
+                    const parentDirPath = toPath(ts.getDirectoryPath(path), currentDirectory, getCanonicalPath);
+                    if (watchedDirectories.contains(parentDirPath)) {
+                        let hasWatchedChildren = false;
+                        watchedFiles.forEachValue((key, _) => {
+                            if (ts.getDirectoryPath(key) === parentDirPath) {
+                                hasWatchedChildren = true;
+                            }
+                        });
+                        if (!hasWatchedChildren) {
+                            watchedDirectories.get(parentDirPath).close();
+                            watchedDirectories.remove(parentDirPath);
+                        }
                     }
                 }
 
-                return {
-                    addFile: addFile,
-                    removeFile: removeFile
-                };
+                function fileEventHandler(eventName: string, fileName: string, basePath: string) {
+                    const path = ts.toPath(fileName, basePath, getCanonicalPath);
+                    if (watchedFiles.contains(path)) {
+                        const callback = watchedFiles.get(path);
+                        callback(fileName);
+                    }
+                }
             }
 
             // REVIEW: for now this implementation uses polling.
@@ -352,7 +357,7 @@ namespace ts {
             // to increase the chunk size or decrease the interval
             // time dynamically to match the large reference set?
             const pollingWatchedFileSet = createPollingWatchedFileSet();
-            // const watchedFileSet = createWatchedFileSet();
+            const watchedFileSet = createWatchedFileSet();
 
             function isNode4OrLater(): Boolean {
                 return parseInt(process.version.charAt(1)) >= 4;
@@ -456,9 +461,10 @@ namespace ts {
                     // and is more efficient than `fs.watchFile` (ref: https://github.com/nodejs/node/pull/2649
                     // and https://github.com/Microsoft/TypeScript/issues/4643), therefore
                     // if the current node.js version is newer than 4, use `fs.watch` instead.
-                    const watchedFile = pollingWatchedFileSet.addFile(fileName, callback);
+                    const watchSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
+                    const watchedFile =  watchSet.addFile(fileName, callback);
                     return {
-                        close: () => pollingWatchedFileSet.removeFile(watchedFile)
+                        close: () => watchSet.removeFile(watchedFile)
                     };
                 },
                 watchDirectory: (path, callback, recursive) => {

From 178b2dabfe7f16824d126fdc6406391faec39f86 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Mon, 21 Dec 2015 16:29:04 -0800
Subject: [PATCH 05/28] Add type alias for filewatching callbacks

---
 src/compiler/core.ts |  4 +++-
 src/compiler/sys.ts  | 28 +++++++++++++++++-----------
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index cae7bd82103..4e74029fb5d 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -612,7 +612,9 @@ namespace ts {
         return path.substr(0, rootLength) + normalized.join(directorySeparator);
     }
 
-    export function getDirectoryPath(path: string) {
+    export function getDirectoryPath(path: Path): Path;
+    export function getDirectoryPath(path: string): string;
+    export function getDirectoryPath(path: string): any {
         return path.substr(0, Math.max(getRootLength(path), path.lastIndexOf(directorySeparator)));
     }
 
diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 5794c861670..5d723425496 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -1,6 +1,9 @@
 /// <reference path="core.ts"/>
 
 namespace ts {
+    export type CallbackForWatchedFile = (path: string, removed?: boolean) => void;
+    export type CallbackForWatchedDirectory = (path: string) => void;
+
     export interface System {
         args: string[];
         newLine: string;
@@ -8,8 +11,8 @@ namespace ts {
         write(s: string): void;
         readFile(path: string, encoding?: string): string;
         writeFile(path: string, data: string, writeByteOrderMark?: boolean): void;
-        watchFile?(path: string, callback: (path: string, removed?: boolean) => void): FileWatcher;
-        watchDirectory?(path: string, callback: (path: string) => void, recursive?: boolean): FileWatcher;
+        watchFile?(path: string, callback: CallbackForWatchedFile): FileWatcher;
+        watchDirectory?(path: string, callback: CallbackForWatchedDirectory, recursive?: boolean): FileWatcher;
         resolvePath(path: string): string;
         fileExists(path: string): boolean;
         directoryExists(path: string): boolean;
@@ -23,7 +26,7 @@ namespace ts {
 
     interface WatchedFile {
         fileName: string;
-        callback: (fileName: string, removed?: boolean) => void;
+        callback: CallbackForWatchedFile;
         mtime?: Date;
     }
 
@@ -62,8 +65,8 @@ namespace ts {
         readFile(path: string): string;
         writeFile(path: string, contents: string): void;
         readDirectory(path: string, extension?: string, exclude?: string[]): string[];
-        watchFile?(path: string, callback: (path: string, removed?: boolean) => void): FileWatcher;
-        watchDirectory?(path: string, callback: (path: string) => void, recursive?: boolean): FileWatcher;
+        watchFile?(path: string, callback: CallbackForWatchedFile): FileWatcher;
+        watchDirectory?(path: string, callback: CallbackForWatchedDirectory, recursive?: boolean): FileWatcher;
     };
 
     export var sys: System = (function () {
@@ -271,7 +274,7 @@ namespace ts {
                     }, interval);
                 }
 
-                function addFile(fileName: string, callback: (fileName: string, removed?: boolean) => void): WatchedFile {
+                function addFile(fileName: string, callback: CallbackForWatchedFile): WatchedFile {
                     const file: WatchedFile = {
                         fileName,
                         callback,
@@ -298,16 +301,18 @@ namespace ts {
                 };
             }
 
+            
+
             function createWatchedFileSet() {
                 const watchedDirectories = createFileMap<FileWatcher>();
-                const watchedFiles = createFileMap<(fileName: string, removed?: boolean) => void>();
+                const watchedFiles = createFileMap<CallbackForWatchedFile>();
                 const currentDirectory = process.cwd();
 
                 return { addFile, removeFile };
 
-                function addFile(fileName: string, callback: (fileName: string, removed?: boolean) => void): WatchedFile {
+                function addFile(fileName: string, callback: CallbackForWatchedFile): WatchedFile {
                     const path = toPath(fileName, currentDirectory, getCanonicalPath);
-                    const parentDirPath = toPath(ts.getDirectoryPath(fileName), currentDirectory, getCanonicalPath);
+                    const parentDirPath = getDirectoryPath(path);
 
                     if (!watchedDirectories.contains(parentDirPath)) {
                         watchedDirectories.set(parentDirPath, _fs.watch(
@@ -323,7 +328,7 @@ namespace ts {
                     const path = toPath(file.fileName, currentDirectory, getCanonicalPath);
                     watchedFiles.remove(path);
 
-                    const parentDirPath = toPath(ts.getDirectoryPath(path), currentDirectory, getCanonicalPath);
+                    const parentDirPath = getDirectoryPath(path);
                     if (watchedDirectories.contains(parentDirPath)) {
                         let hasWatchedChildren = false;
                         watchedFiles.forEachValue((key, _) => {
@@ -474,9 +479,10 @@ namespace ts {
                 watchDirectory: (path, callback, recursive) => {
                     // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
                     // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
+                    const options = isNode4OrLater() ? { persistent: true } : { persistent: true, recursive: !!recursive };
                     return _fs.watch(
                         path,
-                        { persistent: true, recursive: !!recursive },
+                        options,
                         (eventName: string, relativeFileName: string) => {
                             // In watchDirectory we only care about adding and removing files (when event name is
                             // "rename"); changes made within files are handled by corresponding fileWatchers (when

From caa6eb4204a8aa550e493be405ef5b22ef5eebce Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Tue, 22 Dec 2015 15:26:21 -0800
Subject: [PATCH 06/28] Reuse watchers between 'watchDirectory' and 'watchFile'

---
 src/compiler/sys.ts | 184 +++++++++++++++++++++++++++++---------------
 1 file changed, 122 insertions(+), 62 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 5d723425496..4056ffd9da9 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -1,8 +1,8 @@
 /// <reference path="core.ts"/>
 
 namespace ts {
-    export type CallbackForWatchedFile = (path: string, removed?: boolean) => void;
-    export type CallbackForWatchedDirectory = (path: string) => void;
+    export type FileWatcherCallback = (path: string, removed?: boolean) => void;
+    export type DirWatcherCallback = (path: string) => void;
 
     export interface System {
         args: string[];
@@ -11,8 +11,8 @@ namespace ts {
         write(s: string): void;
         readFile(path: string, encoding?: string): string;
         writeFile(path: string, data: string, writeByteOrderMark?: boolean): void;
-        watchFile?(path: string, callback: CallbackForWatchedFile): FileWatcher;
-        watchDirectory?(path: string, callback: CallbackForWatchedDirectory, recursive?: boolean): FileWatcher;
+        watchFile?(path: string, callback: FileWatcherCallback): FileWatcher;
+        watchDirectory?(path: string, callback: DirWatcherCallback, recursive?: boolean): FileWatcher;
         resolvePath(path: string): string;
         fileExists(path: string): boolean;
         directoryExists(path: string): boolean;
@@ -26,13 +26,17 @@ namespace ts {
 
     interface WatchedFile {
         fileName: string;
-        callback: CallbackForWatchedFile;
+        callback: FileWatcherCallback;
         mtime?: Date;
     }
 
     export interface FileWatcher {
         close(): void;
     }
+    
+    export interface DirWatcher extends FileWatcher {
+        referenceCount: number;
+    }
 
     declare var require: any;
     declare var module: any;
@@ -65,8 +69,8 @@ namespace ts {
         readFile(path: string): string;
         writeFile(path: string, contents: string): void;
         readDirectory(path: string, extension?: string, exclude?: string[]): string[];
-        watchFile?(path: string, callback: CallbackForWatchedFile): FileWatcher;
-        watchDirectory?(path: string, callback: CallbackForWatchedDirectory, recursive?: boolean): FileWatcher;
+        watchFile?(path: string, callback: FileWatcherCallback): FileWatcher;
+        watchDirectory?(path: string, callback: DirWatcherCallback, recursive?: boolean): FileWatcher;
     };
 
     export var sys: System = (function () {
@@ -274,7 +278,7 @@ namespace ts {
                     }, interval);
                 }
 
-                function addFile(fileName: string, callback: CallbackForWatchedFile): WatchedFile {
+                function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
                     const file: WatchedFile = {
                         fileName,
                         callback,
@@ -301,53 +305,124 @@ namespace ts {
                 };
             }
 
-            
-
             function createWatchedFileSet() {
-                const watchedDirectories = createFileMap<FileWatcher>();
-                const watchedFiles = createFileMap<CallbackForWatchedFile>();
+                const dirWatchers = createFileMap<DirWatcher>();
+                const recursiveDirWatchers = createFileMap<DirWatcher>();
+                const fileWatcherCallbacks = createFileMap<FileWatcherCallback>();
+                const dirWatcherCallbacks = createFileMap<DirWatcherCallback>();
+
                 const currentDirectory = process.cwd();
+                return { addFile, removeFile, addDir };
 
-                return { addFile, removeFile };
-
-                function addFile(fileName: string, callback: CallbackForWatchedFile): WatchedFile {
-                    const path = toPath(fileName, currentDirectory, getCanonicalPath);
-                    const parentDirPath = getDirectoryPath(path);
-
-                    if (!watchedDirectories.contains(parentDirPath)) {
-                        watchedDirectories.set(parentDirPath, _fs.watch(
-                            parentDirPath,
-                            (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, parentDirPath)
-                        ));
+                function addDir(dirName: string, callback: DirWatcherCallback, recursive?: boolean) {
+                    const dirPath = toPath(dirName, currentDirectory, getCanonicalPath);
+                    dirWatcherCallbacks.set(dirPath, callback);
+                    const { watcher, isRecursive } = addDirWatcher(dirPath, recursive);
+                    return {
+                        close: () => reduceDirWatcherRefCount(watcher, dirPath, isRecursive)
                     }
-                    watchedFiles.set(path, callback);
-                    return { fileName, callback };
                 }
-
-                function removeFile(file: WatchedFile) {
-                    const path = toPath(file.fileName, currentDirectory, getCanonicalPath);
-                    watchedFiles.remove(path);
-
-                    const parentDirPath = getDirectoryPath(path);
-                    if (watchedDirectories.contains(parentDirPath)) {
-                        let hasWatchedChildren = false;
-                        watchedFiles.forEachValue((key, _) => {
-                            if (ts.getDirectoryPath(key) === parentDirPath) {
-                                hasWatchedChildren = true;
-                            }
-                        });
-                        if (!hasWatchedChildren) {
-                            watchedDirectories.get(parentDirPath).close();
-                            watchedDirectories.remove(parentDirPath);
+                
+                function reduceDirWatcherRefCount(watcher: DirWatcher, dirPath: Path, isRecursive: boolean) {
+                    watcher.referenceCount -= 1;
+                    if (watcher.referenceCount <= 0) {
+                        watcher.close();
+                        if (isRecursive) {
+                            recursiveDirWatchers.remove(dirPath);
+                        } else {
+                            dirWatchers.remove(dirPath);
                         }
                     }
                 }
 
-                function fileEventHandler(eventName: string, fileName: string, basePath: string) {
-                    const path = ts.toPath(fileName, basePath, getCanonicalPath);
-                    if (watchedFiles.contains(path)) {
-                        const callback = watchedFiles.get(path);
-                        callback(fileName);
+                function addDirWatcher(dirPath: Path, recursive?: boolean): { watcher: DirWatcher, isRecursive: boolean } {
+                    let watchers: FileMap<DirWatcher>;
+                    let options: { persistent: boolean, recursive?: boolean } = { persistent: true };
+
+                    // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
+                    // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
+                    if (isNode4OrLater() && recursive === true) {
+                        if (recursiveDirWatchers.contains(dirPath)) {
+                            const watcher = recursiveDirWatchers.get(dirPath); 
+                            watcher.referenceCount += 1;
+                            return { watcher, isRecursive: true };
+                        }
+                        watchers = recursiveDirWatchers;
+                        options.recursive = true;
+                    } else {
+                        if (dirWatchers.contains(dirPath)) {
+                            const watcher = dirWatchers.get(dirPath);
+                            watcher.referenceCount += 1;
+                            return { watcher, isRecursive: false };
+                        }
+                        watchers = dirWatchers;
+                    }
+
+                    const watcher: DirWatcher = _fs.watch(dirPath, options, (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath));
+                    watcher.referenceCount = 1;
+                    watchers.set(dirPath, watcher);
+                    return { watcher, isRecursive: false };
+                }
+
+                function findDirWatcherForFile(filePath: Path): { watcher: DirWatcher, watcherPath: Path, isRecursive: boolean } {
+                    let watcher: DirWatcher;
+                    let watcherPath: Path;
+                    let isRecursive = false;
+                    recursiveDirWatchers.forEachValue(dirPath => {
+                        if (filePath.indexOf(dirPath) === 0) {
+                            watcherPath = dirPath;
+                            watcher = recursiveDirWatchers.get(dirPath);
+                            isRecursive = true;
+                            return;
+                        }
+                    });
+                    if (!watcher) {
+                        const parentDirPath = getDirectoryPath(filePath);
+                        if (dirWatchers.contains(parentDirPath)) {
+                            watcherPath = parentDirPath;
+                            watcher = dirWatchers.get(parentDirPath);
+                        }
+                    }
+                    return { watcher, watcherPath, isRecursive };
+                }
+
+                function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
+                    const filePath = toPath(fileName, currentDirectory, getCanonicalPath);
+                    const { watcher } = findDirWatcherForFile(filePath);
+                    if (!watcher) {
+                        addDirWatcher(getDirectoryPath(filePath));
+                    } else {
+                        watcher.referenceCount += 1;
+                    }
+                    fileWatcherCallbacks.set(filePath, callback);
+                    return { fileName, callback };
+                }
+
+                function removeFile(file: WatchedFile) {
+                    const filePath = toPath(file.fileName, currentDirectory, getCanonicalPath);
+                    fileWatcherCallbacks.remove(filePath);
+
+                    const { watcher, watcherPath, isRecursive } = findDirWatcherForFile(filePath);
+                    if (watcher) {
+                        reduceDirWatcherRefCount(watcher, watcherPath, isRecursive);
+                    }
+                }
+
+                /**
+                 * @param watcherPath is the path from which the watcher is triggered.
+                 */
+                function fileEventHandler(eventName: string, relativefileName: string, baseDirPath: Path) {
+                    // When files are deleted from disk, the triggered "rename" event would have a relativefileName of "undefined"
+                    const filePath = relativefileName === undefined ? undefined : toPath(relativefileName, baseDirPath, getCanonicalPath);
+                    // Directory callbacks are not set for file content changes, they are more often used for
+                    // adding/removing/renaming files, which corresponds to the "rename" event
+                    if (eventName === "rename" && dirWatcherCallbacks.contains(baseDirPath)) {
+                        const dirCallback = dirWatcherCallbacks.get(baseDirPath);
+                        dirCallback(filePath);
+                    }
+                    if (fileWatcherCallbacks.contains(filePath)) {
+                        const fileCallback = fileWatcherCallbacks.get(filePath);
+                        fileCallback(filePath);
                     }
                 }
             }
@@ -477,22 +552,7 @@ namespace ts {
                     };
                 },
                 watchDirectory: (path, callback, recursive) => {
-                    // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
-                    // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
-                    const options = isNode4OrLater() ? { persistent: true } : { persistent: true, recursive: !!recursive };
-                    return _fs.watch(
-                        path,
-                        options,
-                        (eventName: string, relativeFileName: string) => {
-                            // In watchDirectory we only care about adding and removing files (when event name is
-                            // "rename"); changes made within files are handled by corresponding fileWatchers (when
-                            // event name is "change")
-                            if (eventName === "rename") {
-                                // When deleting a file, the passed baseFileName is null
-                                callback(!relativeFileName ? relativeFileName : normalizePath(ts.combinePaths(path, relativeFileName)));
-                            };
-                        }
-                    );
+                    return watchedFileSet.addDir(path, callback, recursive);
                 },
                 resolvePath: function (path: string): string {
                     return _path.resolve(path);

From 631363fee19414f4d4cb136f8bf85e8aa061561e Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Tue, 22 Dec 2015 15:38:52 -0800
Subject: [PATCH 07/28] Fix lint issues

---
 src/compiler/sys.ts | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 4056ffd9da9..afac095a56e 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -33,7 +33,7 @@ namespace ts {
     export interface FileWatcher {
         close(): void;
     }
-    
+
     export interface DirWatcher extends FileWatcher {
         referenceCount: number;
     }
@@ -320,16 +320,17 @@ namespace ts {
                     const { watcher, isRecursive } = addDirWatcher(dirPath, recursive);
                     return {
                         close: () => reduceDirWatcherRefCount(watcher, dirPath, isRecursive)
-                    }
+                    };
                 }
-                
+
                 function reduceDirWatcherRefCount(watcher: DirWatcher, dirPath: Path, isRecursive: boolean) {
                     watcher.referenceCount -= 1;
                     if (watcher.referenceCount <= 0) {
                         watcher.close();
                         if (isRecursive) {
                             recursiveDirWatchers.remove(dirPath);
-                        } else {
+                        }
+                        else {
                             dirWatchers.remove(dirPath);
                         }
                     }
@@ -337,19 +338,20 @@ namespace ts {
 
                 function addDirWatcher(dirPath: Path, recursive?: boolean): { watcher: DirWatcher, isRecursive: boolean } {
                     let watchers: FileMap<DirWatcher>;
-                    let options: { persistent: boolean, recursive?: boolean } = { persistent: true };
+                    const options: { persistent: boolean, recursive?: boolean } = { persistent: true };
 
                     // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
                     // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
                     if (isNode4OrLater() && recursive === true) {
                         if (recursiveDirWatchers.contains(dirPath)) {
-                            const watcher = recursiveDirWatchers.get(dirPath); 
+                            const watcher = recursiveDirWatchers.get(dirPath);
                             watcher.referenceCount += 1;
                             return { watcher, isRecursive: true };
                         }
                         watchers = recursiveDirWatchers;
                         options.recursive = true;
-                    } else {
+                    }
+                    else {
                         if (dirWatchers.contains(dirPath)) {
                             const watcher = dirWatchers.get(dirPath);
                             watcher.referenceCount += 1;
@@ -391,7 +393,8 @@ namespace ts {
                     const { watcher } = findDirWatcherForFile(filePath);
                     if (!watcher) {
                         addDirWatcher(getDirectoryPath(filePath));
-                    } else {
+                    }
+                    else {
                         watcher.referenceCount += 1;
                     }
                     fileWatcherCallbacks.set(filePath, callback);

From 8cf1a34f70c76161adc623f835ad7e04b3026e04 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Mon, 28 Dec 2015 14:05:32 -0800
Subject: [PATCH 08/28] enable more than one callbacks for a watched file

---
 src/compiler/sys.ts | 61 +++++++++++++++++++++++++++++++--------------
 1 file changed, 42 insertions(+), 19 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 62baf28f074..a9056756f01 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -307,15 +307,21 @@ namespace ts {
             function createWatchedFileSet() {
                 const dirWatchers = createFileMap<DirWatcher>();
                 const recursiveDirWatchers = createFileMap<DirWatcher>();
-                const fileWatcherCallbacks = createFileMap<FileWatcherCallback>();
-                const dirWatcherCallbacks = createFileMap<DirWatcherCallback>();
+                // One file can have multiple watchers
+                const fileWatcherCallbacks = createFileMap<FileWatcherCallback[]>();
+                const dirWatcherCallbacks = createFileMap<DirWatcherCallback[]>();
 
                 const currentDirectory = process.cwd();
                 return { addFile, removeFile, addDir };
 
                 function addDir(dirName: string, callback: DirWatcherCallback, recursive?: boolean) {
                     const dirPath = toPath(dirName, currentDirectory, getCanonicalPath);
-                    dirWatcherCallbacks.set(dirPath, callback);
+                    if (!dirWatcherCallbacks.contains(dirPath)) {
+                        dirWatcherCallbacks.set(dirPath, [callback]);
+                    }
+                    else {
+                        dirWatcherCallbacks.get(dirPath).push(callback);
+                    }
                     const { watcher, isRecursive } = addDirWatcher(dirPath, recursive);
                     return {
                         close: () => reduceDirWatcherRefCount(watcher, dirPath, isRecursive)
@@ -341,7 +347,8 @@ namespace ts {
 
                     // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
                     // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
-                    if (isNode4OrLater() && recursive === true) {
+                    if (isNode4OrLater() && recursive === true &&
+                        (process.platform === "win32" || process.platform === "darwin")) {
                         if (recursiveDirWatchers.contains(dirPath)) {
                             const watcher = recursiveDirWatchers.get(dirPath);
                             watcher.referenceCount += 1;
@@ -357,12 +364,13 @@ namespace ts {
                             return { watcher, isRecursive: false };
                         }
                         watchers = dirWatchers;
+                        options.recursive = false;
                     }
 
                     const watcher: DirWatcher = _fs.watch(dirPath, options, (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath));
                     watcher.referenceCount = 1;
                     watchers.set(dirPath, watcher);
-                    return { watcher, isRecursive: false };
+                    return { watcher, isRecursive: options.recursive };
                 }
 
                 function findDirWatcherForFile(filePath: Path): { watcher: DirWatcher, watcherPath: Path, isRecursive: boolean } {
@@ -389,24 +397,37 @@ namespace ts {
 
                 function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
                     const filePath = toPath(fileName, currentDirectory, getCanonicalPath);
-                    const { watcher } = findDirWatcherForFile(filePath);
-                    if (!watcher) {
-                        addDirWatcher(getDirectoryPath(filePath));
+
+                    if (fileWatcherCallbacks.contains(filePath)) {
+                        fileWatcherCallbacks.get(filePath).push(callback);
                     }
                     else {
-                        watcher.referenceCount += 1;
+                        const { watcher } = findDirWatcherForFile(filePath);
+                        if (!watcher) {
+                            addDirWatcher(getDirectoryPath(filePath));
+                        }
+                        else {
+                            watcher.referenceCount += 1;
+                        }
+                        fileWatcherCallbacks.set(filePath, [callback]);
                     }
-                    fileWatcherCallbacks.set(filePath, callback);
                     return { fileName, callback };
                 }
 
                 function removeFile(file: WatchedFile) {
                     const filePath = toPath(file.fileName, currentDirectory, getCanonicalPath);
-                    fileWatcherCallbacks.remove(filePath);
-
-                    const { watcher, watcherPath, isRecursive } = findDirWatcherForFile(filePath);
-                    if (watcher) {
-                        reduceDirWatcherRefCount(watcher, watcherPath, isRecursive);
+                    if (fileWatcherCallbacks.contains(filePath)) {
+                        const newCallbacks = copyListRemovingItem(file.callback, fileWatcherCallbacks.get(filePath));
+                        if (newCallbacks.length === 0) {
+                            fileWatcherCallbacks.remove(filePath);
+                            const { watcher, watcherPath, isRecursive } = findDirWatcherForFile(filePath);
+                            if (watcher) {
+                                reduceDirWatcherRefCount(watcher, watcherPath, isRecursive);
+                            }
+                        }
+                        else {
+                            fileWatcherCallbacks.set(filePath, newCallbacks);
+                        }
                     }
                 }
 
@@ -419,12 +440,14 @@ namespace ts {
                     // Directory callbacks are not set for file content changes, they are more often used for
                     // adding/removing/renaming files, which corresponds to the "rename" event
                     if (eventName === "rename" && dirWatcherCallbacks.contains(baseDirPath)) {
-                        const dirCallback = dirWatcherCallbacks.get(baseDirPath);
-                        dirCallback(filePath);
+                        for (const dirCallback of dirWatcherCallbacks.get(baseDirPath)) {
+                            dirCallback(filePath);
+                        }
                     }
                     if (fileWatcherCallbacks.contains(filePath)) {
-                        const fileCallback = fileWatcherCallbacks.get(filePath);
-                        fileCallback(filePath);
+                        for (const fileCallback of fileWatcherCallbacks.get(filePath)) {
+                            fileCallback(filePath);
+                        }
                     }
                 }
             }

From 697644c583aec713927241f20d8fda17a2aefaa8 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Thu, 7 Jan 2016 22:48:17 -0800
Subject: [PATCH 09/28] spell our dir to directory

---
 src/compiler/sys.ts | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index a9056756f01..a99f491175c 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -2,7 +2,7 @@
 
 namespace ts {
     export type FileWatcherCallback = (path: string, removed?: boolean) => void;
-    export type DirWatcherCallback = (path: string) => void;
+    export type DirectoryWatcherCallback = (path: string) => void;
 
     export interface System {
         args: string[];
@@ -12,7 +12,7 @@ namespace ts {
         readFile(path: string, encoding?: string): string;
         writeFile(path: string, data: string, writeByteOrderMark?: boolean): void;
         watchFile?(path: string, callback: FileWatcherCallback): FileWatcher;
-        watchDirectory?(path: string, callback: DirWatcherCallback, recursive?: boolean): FileWatcher;
+        watchDirectory?(path: string, callback: DirectoryWatcherCallback, recursive?: boolean): FileWatcher;
         resolvePath(path: string): string;
         fileExists(path: string): boolean;
         directoryExists(path: string): boolean;
@@ -34,7 +34,7 @@ namespace ts {
         close(): void;
     }
 
-    export interface DirWatcher extends FileWatcher {
+    export interface DirectoryWatcher extends FileWatcher {
         referenceCount: number;
     }
 
@@ -70,7 +70,7 @@ namespace ts {
         writeFile(path: string, contents: string): void;
         readDirectory(path: string, extension?: string, exclude?: string[]): string[];
         watchFile?(path: string, callback: FileWatcherCallback): FileWatcher;
-        watchDirectory?(path: string, callback: DirWatcherCallback, recursive?: boolean): FileWatcher;
+        watchDirectory?(path: string, callback: DirectoryWatcherCallback, recursive?: boolean): FileWatcher;
     };
 
     export var sys: System = (function () {
@@ -305,16 +305,16 @@ namespace ts {
             }
 
             function createWatchedFileSet() {
-                const dirWatchers = createFileMap<DirWatcher>();
-                const recursiveDirWatchers = createFileMap<DirWatcher>();
+                const dirWatchers = createFileMap<DirectoryWatcher>();
+                const recursiveDirWatchers = createFileMap<DirectoryWatcher>();
                 // One file can have multiple watchers
                 const fileWatcherCallbacks = createFileMap<FileWatcherCallback[]>();
-                const dirWatcherCallbacks = createFileMap<DirWatcherCallback[]>();
+                const dirWatcherCallbacks = createFileMap<DirectoryWatcherCallback[]>();
 
                 const currentDirectory = process.cwd();
                 return { addFile, removeFile, addDir };
 
-                function addDir(dirName: string, callback: DirWatcherCallback, recursive?: boolean) {
+                function addDir(dirName: string, callback: DirectoryWatcherCallback, recursive?: boolean) {
                     const dirPath = toPath(dirName, currentDirectory, getCanonicalPath);
                     if (!dirWatcherCallbacks.contains(dirPath)) {
                         dirWatcherCallbacks.set(dirPath, [callback]);
@@ -328,7 +328,7 @@ namespace ts {
                     };
                 }
 
-                function reduceDirWatcherRefCount(watcher: DirWatcher, dirPath: Path, isRecursive: boolean) {
+                function reduceDirWatcherRefCount(watcher: DirectoryWatcher, dirPath: Path, isRecursive: boolean) {
                     watcher.referenceCount -= 1;
                     if (watcher.referenceCount <= 0) {
                         watcher.close();
@@ -341,8 +341,8 @@ namespace ts {
                     }
                 }
 
-                function addDirWatcher(dirPath: Path, recursive?: boolean): { watcher: DirWatcher, isRecursive: boolean } {
-                    let watchers: FileMap<DirWatcher>;
+                function addDirWatcher(dirPath: Path, recursive?: boolean): { watcher: DirectoryWatcher, isRecursive: boolean } {
+                    let watchers: FileMap<DirectoryWatcher>;
                     const options: { persistent: boolean, recursive?: boolean } = { persistent: true };
 
                     // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
@@ -367,14 +367,14 @@ namespace ts {
                         options.recursive = false;
                     }
 
-                    const watcher: DirWatcher = _fs.watch(dirPath, options, (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath));
+                    const watcher: DirectoryWatcher = _fs.watch(dirPath, options, (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath));
                     watcher.referenceCount = 1;
                     watchers.set(dirPath, watcher);
                     return { watcher, isRecursive: options.recursive };
                 }
 
-                function findDirWatcherForFile(filePath: Path): { watcher: DirWatcher, watcherPath: Path, isRecursive: boolean } {
-                    let watcher: DirWatcher;
+                function findDirWatcherForFile(filePath: Path): { watcher: DirectoryWatcher, watcherPath: Path, isRecursive: boolean } {
+                    let watcher: DirectoryWatcher;
                     let watcherPath: Path;
                     let isRecursive = false;
                     recursiveDirWatchers.forEachValue(dirPath => {

From 114d2bd66d849db3aff2ec3401f6a68805fafa8d Mon Sep 17 00:00:00 2001
From: zhengbli <zhengbli@microsoft.com>
Date: Mon, 11 Jan 2016 11:35:46 -0800
Subject: [PATCH 10/28] Separate directory watching and file watching again to
 reduce logic complexity, because reference counting is a lot easier in this
 case

---
 src/compiler/sys.ts | 164 +++++++++++++++++---------------------------
 1 file changed, 63 insertions(+), 101 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index a99f491175c..de56beb8697 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -35,6 +35,7 @@ namespace ts {
     }
 
     export interface DirectoryWatcher extends FileWatcher {
+        directoryPath: Path;
         referenceCount: number;
     }
 
@@ -306,123 +307,71 @@ namespace ts {
 
             function createWatchedFileSet() {
                 const dirWatchers = createFileMap<DirectoryWatcher>();
-                const recursiveDirWatchers = createFileMap<DirectoryWatcher>();
                 // One file can have multiple watchers
                 const fileWatcherCallbacks = createFileMap<FileWatcherCallback[]>();
-                const dirWatcherCallbacks = createFileMap<DirectoryWatcherCallback[]>();
-
                 const currentDirectory = process.cwd();
-                return { addFile, removeFile, addDir };
+                return { addFile, removeFile };
 
-                function addDir(dirName: string, callback: DirectoryWatcherCallback, recursive?: boolean) {
-                    const dirPath = toPath(dirName, currentDirectory, getCanonicalPath);
-                    if (!dirWatcherCallbacks.contains(dirPath)) {
-                        dirWatcherCallbacks.set(dirPath, [callback]);
-                    }
-                    else {
-                        dirWatcherCallbacks.get(dirPath).push(callback);
-                    }
-                    const { watcher, isRecursive } = addDirWatcher(dirPath, recursive);
-                    return {
-                        close: () => reduceDirWatcherRefCount(watcher, dirPath, isRecursive)
-                    };
-                }
-
-                function reduceDirWatcherRefCount(watcher: DirectoryWatcher, dirPath: Path, isRecursive: boolean) {
+                function reduceDirWatcherRefCount(dirPath: Path) {
+                    const watcher = dirWatchers.get(dirPath);
                     watcher.referenceCount -= 1;
                     if (watcher.referenceCount <= 0) {
                         watcher.close();
-                        if (isRecursive) {
-                            recursiveDirWatchers.remove(dirPath);
-                        }
-                        else {
-                            dirWatchers.remove(dirPath);
-                        }
+                        dirWatchers.remove(dirPath);
                     }
                 }
 
-                function addDirWatcher(dirPath: Path, recursive?: boolean): { watcher: DirectoryWatcher, isRecursive: boolean } {
-                    let watchers: FileMap<DirectoryWatcher>;
-                    const options: { persistent: boolean, recursive?: boolean } = { persistent: true };
-
-                    // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
-                    // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
-                    if (isNode4OrLater() && recursive === true &&
-                        (process.platform === "win32" || process.platform === "darwin")) {
-                        if (recursiveDirWatchers.contains(dirPath)) {
-                            const watcher = recursiveDirWatchers.get(dirPath);
-                            watcher.referenceCount += 1;
-                            return { watcher, isRecursive: true };
-                        }
-                        watchers = recursiveDirWatchers;
-                        options.recursive = true;
-                    }
-                    else {
-                        if (dirWatchers.contains(dirPath)) {
-                            const watcher = dirWatchers.get(dirPath);
-                            watcher.referenceCount += 1;
-                            return { watcher, isRecursive: false };
-                        }
-                        watchers = dirWatchers;
-                        options.recursive = false;
+                function addDirWatcher(dirPath: Path): void {
+                    if (dirWatchers.contains(dirPath)) {
+                        const watcher = dirWatchers.get(dirPath);
+                        watcher.referenceCount += 1;
+                        return;
                     }
 
-                    const watcher: DirectoryWatcher = _fs.watch(dirPath, options, (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath));
+                    const watcher: DirectoryWatcher = _fs.watch(
+                        dirPath, 
+                        { persistent: true }, 
+                        (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath)
+                    );
                     watcher.referenceCount = 1;
-                    watchers.set(dirPath, watcher);
-                    return { watcher, isRecursive: options.recursive };
+                    dirWatchers.set(dirPath, watcher);
+                    return;
                 }
 
-                function findDirWatcherForFile(filePath: Path): { watcher: DirectoryWatcher, watcherPath: Path, isRecursive: boolean } {
-                    let watcher: DirectoryWatcher;
-                    let watcherPath: Path;
-                    let isRecursive = false;
-                    recursiveDirWatchers.forEachValue(dirPath => {
-                        if (filePath.indexOf(dirPath) === 0) {
-                            watcherPath = dirPath;
-                            watcher = recursiveDirWatchers.get(dirPath);
-                            isRecursive = true;
-                            return;
-                        }
-                    });
-                    if (!watcher) {
-                        const parentDirPath = getDirectoryPath(filePath);
-                        if (dirWatchers.contains(parentDirPath)) {
-                            watcherPath = parentDirPath;
-                            watcher = dirWatchers.get(parentDirPath);
-                        }
-                    }
-                    return { watcher, watcherPath, isRecursive };
-                }
-
-                function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
-                    const filePath = toPath(fileName, currentDirectory, getCanonicalPath);
-
+                function addFileWatcherCallback(filePath: Path, callback: FileWatcherCallback): void {
                     if (fileWatcherCallbacks.contains(filePath)) {
                         fileWatcherCallbacks.get(filePath).push(callback);
                     }
                     else {
-                        const { watcher } = findDirWatcherForFile(filePath);
-                        if (!watcher) {
-                            addDirWatcher(getDirectoryPath(filePath));
-                        }
-                        else {
-                            watcher.referenceCount += 1;
-                        }
                         fileWatcherCallbacks.set(filePath, [callback]);
                     }
+                }
+
+                function findWatchedDirForFile(filePath: Path): Path {
+                    const dirPath = getDirectoryPath(filePath);
+                    if (dirWatchers.contains(dirPath)) {
+                        return dirPath;
+                    }
+                    return undefined;
+                }
+
+                function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
+                    const filePath = toPath(fileName, currentDirectory, getCanonicalPath);
+                    addFileWatcherCallback(filePath, callback);
+                    addDirWatcher(getDirectoryPath(filePath));
+
                     return { fileName, callback };
                 }
 
-                function removeFile(file: WatchedFile) {
-                    const filePath = toPath(file.fileName, currentDirectory, getCanonicalPath);
+                function removeFile(watchedFile: WatchedFile) {
+                    const filePath = toPath(watchedFile.fileName, currentDirectory, getCanonicalPath);
                     if (fileWatcherCallbacks.contains(filePath)) {
-                        const newCallbacks = copyListRemovingItem(file.callback, fileWatcherCallbacks.get(filePath));
+                        const newCallbacks = copyListRemovingItem(watchedFile.callback, fileWatcherCallbacks.get(filePath));
                         if (newCallbacks.length === 0) {
                             fileWatcherCallbacks.remove(filePath);
-                            const { watcher, watcherPath, isRecursive } = findDirWatcherForFile(filePath);
-                            if (watcher) {
-                                reduceDirWatcherRefCount(watcher, watcherPath, isRecursive);
+                            const watchedDir = findWatchedDirForFile(filePath);
+                            if (watchedDir) {
+                                reduceDirWatcherRefCount(watchedDir);
                             }
                         }
                         else {
@@ -437,14 +386,7 @@ namespace ts {
                 function fileEventHandler(eventName: string, relativefileName: string, baseDirPath: Path) {
                     // When files are deleted from disk, the triggered "rename" event would have a relativefileName of "undefined"
                     const filePath = relativefileName === undefined ? undefined : toPath(relativefileName, baseDirPath, getCanonicalPath);
-                    // Directory callbacks are not set for file content changes, they are more often used for
-                    // adding/removing/renaming files, which corresponds to the "rename" event
-                    if (eventName === "rename" && dirWatcherCallbacks.contains(baseDirPath)) {
-                        for (const dirCallback of dirWatcherCallbacks.get(baseDirPath)) {
-                            dirCallback(filePath);
-                        }
-                    }
-                    if (fileWatcherCallbacks.contains(filePath)) {
+                    if (eventName === "change" && fileWatcherCallbacks.contains(filePath)) {
                         for (const fileCallback of fileWatcherCallbacks.get(filePath)) {
                             fileCallback(filePath);
                         }
@@ -577,7 +519,29 @@ namespace ts {
                     };
                 },
                 watchDirectory: (path, callback, recursive) => {
-                    return watchedFileSet.addDir(path, callback, recursive);
+                    // Node 4.0 `fs.watch` function supports the "recursive" option on both OSX and Windows
+                    // (ref: https://github.com/nodejs/node/pull/2649 and https://github.com/Microsoft/TypeScript/issues/4643)
+                    let options: any;
+                    if (isNode4OrLater() && (process.platform === "win32" || process.platform === "darwin")) {
+                        options = { persistent: true, recursive: !!recursive };
+                    }
+                    else {
+                        options = { persistent: true };
+                    }
+
+                    return _fs.watch(
+                        path,
+                        options,
+                        (eventName: string, relativeFileName: string) => {
+                            // In watchDirectory we only care about adding and removing files (when event name is
+                            // "rename"); changes made within files are handled by corresponding fileWatchers (when
+                            // event name is "change")
+                            if (eventName === "rename") {
+                                // When deleting a file, the passed baseFileName is null
+                                callback(!relativeFileName ? relativeFileName : normalizePath(combinePaths(path, relativeFileName)));
+                            };
+                        }
+                    );
                 },
                 resolvePath: function (path: string): string {
                     return _path.resolve(path);
@@ -658,5 +622,3 @@ namespace ts {
         }
     })();
 }
-
-

From d22626f32db719801256cac2f888b0cb9c0f150a Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Tue, 12 Jan 2016 00:17:38 -0800
Subject: [PATCH 11/28] Fix lint issue

---
 src/compiler/sys.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index de56beb8697..f40de0bd65e 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -329,8 +329,8 @@ namespace ts {
                     }
 
                     const watcher: DirectoryWatcher = _fs.watch(
-                        dirPath, 
-                        { persistent: true }, 
+                        dirPath,
+                        { persistent: true },
                         (eventName: string, relativeFileName: string) => fileEventHandler(eventName, relativeFileName, dirPath)
                     );
                     watcher.referenceCount = 1;

From 5ba47eca864ca2493d1dd902095e8ce2fc9fec8a Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:18:51 +0200
Subject: [PATCH 12/28] added two new more specific messages

---
 src/compiler/diagnosticMessages.json | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 28b10dd73b4..7f1c195ae20 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -1775,6 +1775,14 @@
         "category": "Error",
         "code": 2661
     },
+    "Cannot find name '{0}'. Did you mean to prefix the static member with the class name, '{1}.{0}'?": {
+        "category": "Error",
+        "code": 2662
+    },
+    "Cannot find name '{0}'. Did you mean to prefix the object member with 'this', 'this.{0}'?": {
+        "category": "Error",
+        "code": 2663
+    },
     "Import declaration '{0}' is using private name '{1}'.": {
         "category": "Error",
         "code": 4000

From 6b7b9aaa5608f1c40c6dbe1daf4365caa58c0aff Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:20:34 +0200
Subject: [PATCH 13/28] added check for missing prefix

---
 src/compiler/checker.ts | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 4c1ef08ddd6..fdce825e292 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -740,7 +740,9 @@ namespace ts {
 
             if (!result) {
                 if (nameNotFoundMessage) {
-                    error(errorLocation, nameNotFoundMessage, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
+                    if (!checkForMissingPrefix(errorLocation, name, nameArg)) {
+                        error(errorLocation, nameNotFoundMessage, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
+                    }
                 }
                 return undefined;
             }
@@ -777,6 +779,39 @@ namespace ts {
             return result;
         }
 
+        function checkForMissingPrefix(errorLocation: Node, name: string, nameArg: string | Identifier): boolean {
+            if (!errorLocation || (errorLocation.kind === SyntaxKind.Identifier && (isTypeReferenceIdentifier(<Identifier>errorLocation)) || isInTypeQuery(errorLocation))) {
+                return false;
+            }
+            const container = getThisContainer(errorLocation, /* includeArrowFunctions */ true);
+            let location = container;
+            while (location) {
+                if (isClassLike(location.parent)) {
+                    const symbol = getSymbolOfNode(location.parent);
+                    let classType: Type;
+                    if (location.flags & NodeFlags.Static) {
+                        classType = getTypeOfSymbol(symbol);
+                        if (getPropertyOfType(classType, name)) {
+                            error(errorLocation, Diagnostics.Cannot_find_name_0_Did_you_mean_to_prefix_the_static_member_with_the_class_name_1_0, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg), symbolToString(symbol));
+                            return true;
+                        }
+                    }
+                    else {
+                        if (location === container) {
+                            classType = (<InterfaceType>getDeclaredTypeOfSymbol(symbol)).thisType;
+                            if (getPropertyOfType(classType, name)) {
+                                error(errorLocation, Diagnostics.Cannot_find_name_0_Did_you_mean_to_prefix_the_object_member_with_this_this_0, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
+                                return true;
+                            }
+                        }
+                    }
+                }
+
+                location = location.parent;
+            }
+            return false;
+        }
+
         function checkResolvedBlockScopedVariable(result: Symbol, errorLocation: Node): void {
             Debug.assert((result.flags & SymbolFlags.BlockScopedVariable) !== 0);
             // Block-scoped variables cannot be used before their definition

From 7f8dd6bb7459ae9959ccdf94889ccab66cf893f5 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:20:58 +0200
Subject: [PATCH 14/28] fixed initializerReferencingConstructorParameters test

---
 ...initializerReferencingConstructorParameters.errors.txt | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt b/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt
index 623bd535745..03e4e83e409 100644
--- a/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt
+++ b/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(4,9): error TS2304: Cannot find name 'x'.
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(5,15): error TS2304: Cannot find name 'x'.
-tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(10,9): error TS2304: Cannot find name 'x'.
+tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(10,9): error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(11,15): error TS2304: Cannot find name 'x'.
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(17,15): error TS1003: Identifier expected.
-tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(23,9): error TS2304: Cannot find name 'x'.
+tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(23,9): error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
 
 
 ==== tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts (6 errors) ====
@@ -22,7 +22,7 @@ tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencin
     class D {
         a = x; // error
             ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
         b: typeof x; // error
                   ~
 !!! error TS2304: Cannot find name 'x'.
@@ -41,6 +41,6 @@ tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencin
         a = this.x; // ok
         b = x; // error
             ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
         constructor(public x: T) { }
     }
\ No newline at end of file

From 2ef9f69a7ec011ff4137d5efdcabd063dd63a521 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:21:15 +0200
Subject: [PATCH 15/28] fixed YieldExpression11_es6 test

---
 tests/baselines/reference/YieldExpression11_es6.errors.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/baselines/reference/YieldExpression11_es6.errors.txt b/tests/baselines/reference/YieldExpression11_es6.errors.txt
index c19e8b6cfa5..4a2f93a9c6d 100644
--- a/tests/baselines/reference/YieldExpression11_es6.errors.txt
+++ b/tests/baselines/reference/YieldExpression11_es6.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(2,3): error TS1220: Generators are only available when targeting ECMAScript 6 or higher.
-tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(3,11): error TS2304: Cannot find name 'foo'.
+tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(3,11): error TS2663: Cannot find name 'foo'. Did you mean to prefix the object member with 'this', 'this.foo'?
 
 
 ==== tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts (2 errors) ====
@@ -9,6 +9,6 @@ tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(3,11): err
 !!! error TS1220: Generators are only available when targeting ECMAScript 6 or higher.
         yield(foo);
               ~~~
-!!! error TS2304: Cannot find name 'foo'.
+!!! error TS2663: Cannot find name 'foo'. Did you mean to prefix the object member with 'this', 'this.foo'?
       }
     }
\ No newline at end of file

From fe39e0c838a2db0bcc2881be2084a0b8bbca5e51 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:22:31 +0200
Subject: [PATCH 16/28] fixed parserharness test

---
 .../reference/parserharness.errors.txt        | 20 +++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/tests/baselines/reference/parserharness.errors.txt b/tests/baselines/reference/parserharness.errors.txt
index 66afa3d010f..711d3fd9aac 100644
--- a/tests/baselines/reference/parserharness.errors.txt
+++ b/tests/baselines/reference/parserharness.errors.txt
@@ -7,11 +7,11 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(25,17): er
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(41,12): error TS2304: Cannot find name 'ActiveXObject'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(43,19): error TS2304: Cannot find name 'require'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(44,14): error TS2304: Cannot find name 'require'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(341,13): error TS2304: Cannot find name 'errorHandlerStack'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(347,13): error TS2304: Cannot find name 'errorHandlerStack'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(351,17): error TS2304: Cannot find name 'errorHandlerStack'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,17): error TS2304: Cannot find name 'errorHandlerStack'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,35): error TS2304: Cannot find name 'errorHandlerStack'.
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(341,13): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(347,13): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(351,17): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,17): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,35): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(691,50): error TS2304: Cannot find name 'ITextWriter'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(716,47): error TS2503: Cannot find namespace 'TypeScript'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(721,62): error TS2304: Cannot find name 'ITextWriter'.
@@ -471,7 +471,7 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(2030,32):
             static pushGlobalErrorHandler(done: IDone) {
                 errorHandlerStack.push(function (e) {
                 ~~~~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'errorHandlerStack'.
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
                     done(e);
                 });
             }
@@ -479,20 +479,20 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(2030,32):
             static popGlobalErrorHandler() {
                 errorHandlerStack.pop();
                 ~~~~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'errorHandlerStack'.
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
             }
     
             static handleError(e: Error) {
                 if (errorHandlerStack.length === 0) {
                     ~~~~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'errorHandlerStack'.
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
                     IO.printLine('Global error: ' + e);
                 } else {
                     errorHandlerStack[errorHandlerStack.length - 1](e);
                     ~~~~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'errorHandlerStack'.
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
                                       ~~~~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'errorHandlerStack'.
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
                 }
             }
         }

From 217b0d48b24ef9a6cc2b15878ffcd7183bd159a4 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:24:10 +0200
Subject: [PATCH 17/28] fixed parserindenter test

---
 tests/baselines/reference/parserindenter.errors.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/baselines/reference/parserindenter.errors.txt b/tests/baselines/reference/parserindenter.errors.txt
index a332abab7bb..d892f27579f 100644
--- a/tests/baselines/reference/parserindenter.errors.txt
+++ b/tests/baselines/reference/parserindenter.errors.txt
@@ -28,7 +28,7 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(152,63):
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(153,30): error TS2304: Cannot find name 'List_TextEditInfo'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(155,32): error TS2304: Cannot find name 'AuthorTokenKind'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(182,79): error TS2503: Cannot find namespace 'Services'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(183,20): error TS2304: Cannot find name 'GetIndentSizeFromText'.
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(183,20): error TS2662: Cannot find name 'GetIndentSizeFromText'. Did you mean to prefix the static member with the class name, 'Indenter.GetIndentSizeFromText'?
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(186,67): error TS2503: Cannot find namespace 'Services'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(207,50): error TS2304: Cannot find name 'TokenSpan'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(207,67): error TS2304: Cannot find name 'ParseNode'.
@@ -373,7 +373,7 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(736,38):
 !!! error TS2503: Cannot find namespace 'Services'.
                 return GetIndentSizeFromText(indentText, editorOptions, /*includeNonIndentChars:*/ false);
                        ~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'GetIndentSizeFromText'.
+!!! error TS2662: Cannot find name 'GetIndentSizeFromText'. Did you mean to prefix the static member with the class name, 'Indenter.GetIndentSizeFromText'?
             }
     
             static GetIndentSizeFromText(text: string, editorOptions: Services.EditorOptions, includeNonIndentChars: boolean): number {

From 00a46cc3928d756186fb6250176bf9bcb6d70a73 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:24:59 +0200
Subject: [PATCH 18/28] fixed scannertest1 test

---
 tests/baselines/reference/scannertest1.errors.txt | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/tests/baselines/reference/scannertest1.errors.txt b/tests/baselines/reference/scannertest1.errors.txt
index 14a19b28851..234923b5a2f 100644
--- a/tests/baselines/reference/scannertest1.errors.txt
+++ b/tests/baselines/reference/scannertest1.errors.txt
@@ -1,14 +1,14 @@
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(1,1): error TS6053: File 'tests/cases/conformance/scanner/ecmascript5/References.ts' not found.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(5,21): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(5,47): error TS2304: Cannot find name 'CharacterCodes'.
-tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(9,16): error TS2304: Cannot find name 'isDecimalDigit'.
+tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(9,16): error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(10,22): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(10,47): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(11,22): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(11,47): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(15,9): error TS2304: Cannot find name 'Debug'.
-tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(15,22): error TS2304: Cannot find name 'isHexDigit'.
-tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(16,16): error TS2304: Cannot find name 'isDecimalDigit'.
+tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(15,22): error TS2662: Cannot find name 'isHexDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isHexDigit'?
+tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(16,16): error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(17,20): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(18,21): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(18,46): error TS2304: Cannot find name 'CharacterCodes'.
@@ -33,7 +33,7 @@ tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(20,23): error TS2304
         public static isHexDigit(c: number): boolean {
             return isDecimalDigit(c) ||
                    ~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'isDecimalDigit'.
+!!! error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
                    (c >= CharacterCodes.A && c <= CharacterCodes.F) ||
                          ~~~~~~~~~~~~~~
 !!! error TS2304: Cannot find name 'CharacterCodes'.
@@ -51,10 +51,10 @@ tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(20,23): error TS2304
             ~~~~~
 !!! error TS2304: Cannot find name 'Debug'.
                          ~~~~~~~~~~
-!!! error TS2304: Cannot find name 'isHexDigit'.
+!!! error TS2662: Cannot find name 'isHexDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isHexDigit'?
             return isDecimalDigit(c)
                    ~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'isDecimalDigit'.
+!!! error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
                 ? (c - CharacterCodes._0)
                        ~~~~~~~~~~~~~~
 !!! error TS2304: Cannot find name 'CharacterCodes'.

From 90ec38affc014e6245578c654788d016b5ec46b5 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:26:32 +0200
Subject: [PATCH 19/28] fixed recursiveClassReferenceTest test

---
 .../reference/recursiveClassReferenceTest.errors.txt      | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/baselines/reference/recursiveClassReferenceTest.errors.txt b/tests/baselines/reference/recursiveClassReferenceTest.errors.txt
index 088d7222f48..76563a19b5a 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.errors.txt
+++ b/tests/baselines/reference/recursiveClassReferenceTest.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/compiler/recursiveClassReferenceTest.ts(16,19): error TS2304: Cannot find name 'Element'.
-tests/cases/compiler/recursiveClassReferenceTest.ts(56,11): error TS2304: Cannot find name 'domNode'.
-tests/cases/compiler/recursiveClassReferenceTest.ts(88,36): error TS2304: Cannot find name 'mode'.
+tests/cases/compiler/recursiveClassReferenceTest.ts(56,11): error TS2663: Cannot find name 'domNode'. Did you mean to prefix the object member with 'this', 'this.domNode'?
+tests/cases/compiler/recursiveClassReferenceTest.ts(88,36): error TS2663: Cannot find name 'mode'. Did you mean to prefix the object member with 'this', 'this.mode'?
 tests/cases/compiler/recursiveClassReferenceTest.ts(95,21): error TS2345: Argument of type 'Window' is not assignable to parameter of type 'IMode'.
   Property 'getInitialState' is missing in type 'Window'.
 
@@ -65,7 +65,7 @@ tests/cases/compiler/recursiveClassReferenceTest.ts(95,21): error TS2345: Argume
     		public getDomNode() {
     			return domNode;
     			       ~~~~~~~
-!!! error TS2304: Cannot find name 'domNode'.
+!!! error TS2663: Cannot find name 'domNode'. Did you mean to prefix the object member with 'this', 'this.domNode'?
     		}
     		
     		public destroy() {
@@ -99,7 +99,7 @@ tests/cases/compiler/recursiveClassReferenceTest.ts(95,21): error TS2345: Argume
     		
     		public getMode(): IMode { return mode; }
     		                                 ~~~~
-!!! error TS2304: Cannot find name 'mode'.
+!!! error TS2663: Cannot find name 'mode'. Did you mean to prefix the object member with 'this', 'this.mode'?
     	}
     	
     	export class Mode extends AbstractMode {

From 1d817d2337631e525fc5cda2f0c1c09e0453bda1 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:28:39 +0200
Subject: [PATCH 20/28] fixed scopeCheckExtendedClassInsidePublicMethod2 test

---
 .../scopeCheckExtendedClassInsidePublicMethod2.errors.txt     | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt
index c59171bdf0e..d8fbf512bcd 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(4,7): error TS2304: Cannot find name 'v'.
+tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(4,7): error TS2663: Cannot find name 'v'. Did you mean to prefix the object member with 'this', 'this.v'?
 tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(6,7): error TS2304: Cannot find name 's'.
 
 
@@ -8,7 +8,7 @@ tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(6,7): error T
        public c() {
           v = 1;
           ~
-!!! error TS2304: Cannot find name 'v'.
+!!! error TS2663: Cannot find name 'v'. Did you mean to prefix the object member with 'this', 'this.v'?
           this.p = 1;
           s = 1;
           ~

From da5235fc513895c8933f7bc26bb3711674ada24c Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:34:55 +0200
Subject: [PATCH 21/28] fixed scopeCheckExtendedClassInsideStaticMethod1 test

---
 .../scopeCheckExtendedClassInsideStaticMethod1.errors.txt     | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt
index a6ecd488278..ac9381272e8 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(4,7): error TS2304: Cannot find name 'v'.
 tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(5,12): error TS2339: Property 'p' does not exist on type 'typeof D'.
-tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(6,7): error TS2304: Cannot find name 's'.
+tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(6,7): error TS2662: Cannot find name 's'. Did you mean to prefix the static member with the class name, 'D.s'?
 
 
 ==== tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts (3 errors) ====
@@ -15,6 +15,6 @@ tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(6,7): error T
 !!! error TS2339: Property 'p' does not exist on type 'typeof D'.
           s = 1;
           ~
-!!! error TS2304: Cannot find name 's'.
+!!! error TS2662: Cannot find name 's'. Did you mean to prefix the static member with the class name, 'D.s'?
        }
     }
\ No newline at end of file

From dc426683aff2fd92ae9b9c1c0121c8a2789c97f6 Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Wed, 13 Jan 2016 20:35:49 +0200
Subject: [PATCH 22/28] fixed unqualifiedCallToClassStatic1 test

---
 .../reference/unqualifiedCallToClassStatic1.errors.txt        | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt b/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt
index af9edd115e9..190ea245459 100644
--- a/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt
+++ b/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/unqualifiedCallToClassStatic1.ts(4,3): error TS2304: Cannot find name 'foo'.
+tests/cases/compiler/unqualifiedCallToClassStatic1.ts(4,3): error TS2662: Cannot find name 'foo'. Did you mean to prefix the static member with the class name, 'Vector.foo'?
 
 
 ==== tests/cases/compiler/unqualifiedCallToClassStatic1.ts (1 errors) ====
@@ -7,6 +7,6 @@ tests/cases/compiler/unqualifiedCallToClassStatic1.ts(4,3): error TS2304: Cannot
       // 'foo' cannot be called in an unqualified manner.
       foo();
       ~~~
-!!! error TS2304: Cannot find name 'foo'.
+!!! error TS2662: Cannot find name 'foo'. Did you mean to prefix the static member with the class name, 'Vector.foo'?
      }
     }
\ No newline at end of file

From 02531af991ff3c7d420f5ff804d0806626ff11d7 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Wed, 13 Jan 2016 13:18:28 -0800
Subject: [PATCH 23/28] Update the watchedFileSet to use Path instead of string
 for file names

---
 src/compiler/sys.ts | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index f40de0bd65e..822ea5c1921 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -25,7 +25,7 @@ namespace ts {
     }
 
     interface WatchedFile {
-        fileName: string;
+        filePath: Path;
         callback: FileWatcherCallback;
         mtime?: Date;
     }
@@ -244,13 +244,13 @@ namespace ts {
                         return;
                     }
 
-                    _fs.stat(watchedFile.fileName, (err: any, stats: any) => {
+                    _fs.stat(watchedFile.filePath, (err: any, stats: any) => {
                         if (err) {
-                            watchedFile.callback(watchedFile.fileName);
+                            watchedFile.callback(watchedFile.filePath);
                         }
                         else if (watchedFile.mtime.getTime() !== stats.mtime.getTime()) {
-                            watchedFile.mtime = getModifiedTime(watchedFile.fileName);
-                            watchedFile.callback(watchedFile.fileName, watchedFile.mtime.getTime() === 0);
+                            watchedFile.mtime = getModifiedTime(watchedFile.filePath);
+                            watchedFile.callback(watchedFile.filePath, watchedFile.mtime.getTime() === 0);
                         }
                     });
                 }
@@ -278,11 +278,11 @@ namespace ts {
                     }, interval);
                 }
 
-                function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
+                function addFile(filePath: Path, callback: FileWatcherCallback): WatchedFile {
                     const file: WatchedFile = {
-                        fileName,
+                        filePath,
                         callback,
-                        mtime: getModifiedTime(fileName)
+                        mtime: getModifiedTime(filePath)
                     };
 
                     watchedFiles.push(file);
@@ -309,7 +309,6 @@ namespace ts {
                 const dirWatchers = createFileMap<DirectoryWatcher>();
                 // One file can have multiple watchers
                 const fileWatcherCallbacks = createFileMap<FileWatcherCallback[]>();
-                const currentDirectory = process.cwd();
                 return { addFile, removeFile };
 
                 function reduceDirWatcherRefCount(dirPath: Path) {
@@ -355,16 +354,15 @@ namespace ts {
                     return undefined;
                 }
 
-                function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
-                    const filePath = toPath(fileName, currentDirectory, getCanonicalPath);
+                function addFile(filePath: Path, callback: FileWatcherCallback): WatchedFile {
                     addFileWatcherCallback(filePath, callback);
                     addDirWatcher(getDirectoryPath(filePath));
 
-                    return { fileName, callback };
+                    return { filePath, callback };
                 }
 
                 function removeFile(watchedFile: WatchedFile) {
-                    const filePath = toPath(watchedFile.fileName, currentDirectory, getCanonicalPath);
+                    const filePath = watchedFile.filePath;
                     if (fileWatcherCallbacks.contains(filePath)) {
                         const newCallbacks = copyListRemovingItem(watchedFile.callback, fileWatcherCallbacks.get(filePath));
                         if (newCallbacks.length === 0) {
@@ -513,7 +511,7 @@ namespace ts {
                     // and https://github.com/Microsoft/TypeScript/issues/4643), therefore
                     // if the current node.js version is newer than 4, use `fs.watch` instead.
                     const watchSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
-                    const watchedFile =  watchSet.addFile(fileName, callback);
+                    const watchedFile =  watchSet.addFile(<Path>fileName, callback);
                     return {
                         close: () => watchSet.removeFile(watchedFile)
                     };

From 05b1dffc88ab6be902fafa82696d330a9686599d Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Thu, 14 Jan 2016 00:01:59 +0200
Subject: [PATCH 24/28] changed name of checkForMissingPrefix to
 checkAndReportErrorForMissingPrefix

---
 src/compiler/checker.ts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index fdce825e292..1df5a625c2b 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -740,7 +740,7 @@ namespace ts {
 
             if (!result) {
                 if (nameNotFoundMessage) {
-                    if (!checkForMissingPrefix(errorLocation, name, nameArg)) {
+                    if (!checkAndReportErrorForMissingPrefix(errorLocation, name, nameArg)) {
                         error(errorLocation, nameNotFoundMessage, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
                     }
                 }
@@ -779,10 +779,11 @@ namespace ts {
             return result;
         }
 
-        function checkForMissingPrefix(errorLocation: Node, name: string, nameArg: string | Identifier): boolean {
+        function checkAndReportErrorForMissingPrefix(errorLocation: Node, name: string, nameArg: string | Identifier): boolean {
             if (!errorLocation || (errorLocation.kind === SyntaxKind.Identifier && (isTypeReferenceIdentifier(<Identifier>errorLocation)) || isInTypeQuery(errorLocation))) {
                 return false;
             }
+
             const container = getThisContainer(errorLocation, /* includeArrowFunctions */ true);
             let location = container;
             while (location) {

From 067573b0c3e387835452f1d703b877f055f4cbc5 Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Wed, 13 Jan 2016 14:02:34 -0800
Subject: [PATCH 25/28] cr feedback: simplify the removeFile function

---
 src/compiler/sys.ts | 35 +++++++++++++++--------------------
 1 file changed, 15 insertions(+), 20 deletions(-)

diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 822ea5c1921..073a662ce1c 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -311,12 +311,15 @@ namespace ts {
                 const fileWatcherCallbacks = createFileMap<FileWatcherCallback[]>();
                 return { addFile, removeFile };
 
-                function reduceDirWatcherRefCount(dirPath: Path) {
-                    const watcher = dirWatchers.get(dirPath);
-                    watcher.referenceCount -= 1;
-                    if (watcher.referenceCount <= 0) {
-                        watcher.close();
-                        dirWatchers.remove(dirPath);
+                function reduceDirWatcherRefCountForFile(filePath: Path) {
+                    const dirPath = getDirectoryPath(filePath);
+                    if (dirWatchers.contains(dirPath)) {
+                        const watcher = dirWatchers.get(dirPath);
+                        watcher.referenceCount -= 1;
+                        if (watcher.referenceCount <= 0) {
+                            watcher.close();
+                            dirWatchers.remove(dirPath);
+                        }
                     }
                 }
 
@@ -346,14 +349,6 @@ namespace ts {
                     }
                 }
 
-                function findWatchedDirForFile(filePath: Path): Path {
-                    const dirPath = getDirectoryPath(filePath);
-                    if (dirWatchers.contains(dirPath)) {
-                        return dirPath;
-                    }
-                    return undefined;
-                }
-
                 function addFile(filePath: Path, callback: FileWatcherCallback): WatchedFile {
                     addFileWatcherCallback(filePath, callback);
                     addDirWatcher(getDirectoryPath(filePath));
@@ -362,15 +357,15 @@ namespace ts {
                 }
 
                 function removeFile(watchedFile: WatchedFile) {
-                    const filePath = watchedFile.filePath;
+                    removeFileWatcherCallback(watchedFile.filePath, watchedFile.callback);
+                    reduceDirWatcherRefCountForFile(watchedFile.filePath);
+                }
+
+                function removeFileWatcherCallback(filePath: Path, callback: FileWatcherCallback) {
                     if (fileWatcherCallbacks.contains(filePath)) {
-                        const newCallbacks = copyListRemovingItem(watchedFile.callback, fileWatcherCallbacks.get(filePath));
+                        const newCallbacks = copyListRemovingItem(callback, fileWatcherCallbacks.get(filePath));
                         if (newCallbacks.length === 0) {
                             fileWatcherCallbacks.remove(filePath);
-                            const watchedDir = findWatchedDirForFile(filePath);
-                            if (watchedDir) {
-                                reduceDirWatcherRefCount(watchedDir);
-                            }
                         }
                         else {
                             fileWatcherCallbacks.set(filePath, newCallbacks);

From 21baedfebab8224ac5ed0168b35b38fbd7ed6f4f Mon Sep 17 00:00:00 2001
From: "shyyko.serhiy@gmail.com" <shyyko.serhiy@gmail.com>
Date: Thu, 14 Jan 2016 01:14:33 +0200
Subject: [PATCH 26/28] changed messages text in
 checkAndReportErrorForMissingPrefix

---
 src/compiler/checker.ts                       |  4 ++--
 src/compiler/diagnosticMessages.json          |  4 ++--
 .../YieldExpression11_es6.errors.txt          |  4 ++--
 ...eferencingConstructorParameters.errors.txt |  8 ++++----
 .../reference/parserharness.errors.txt        | 20 +++++++++----------
 .../reference/parserindenter.errors.txt       |  4 ++--
 .../recursiveClassReferenceTest.errors.txt    |  8 ++++----
 .../reference/scannertest1.errors.txt         | 12 +++++------
 ...xtendedClassInsidePublicMethod2.errors.txt |  4 ++--
 ...xtendedClassInsideStaticMethod1.errors.txt |  4 ++--
 .../unqualifiedCallToClassStatic1.errors.txt  |  4 ++--
 11 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 1df5a625c2b..d618397f885 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -793,7 +793,7 @@ namespace ts {
                     if (location.flags & NodeFlags.Static) {
                         classType = getTypeOfSymbol(symbol);
                         if (getPropertyOfType(classType, name)) {
-                            error(errorLocation, Diagnostics.Cannot_find_name_0_Did_you_mean_to_prefix_the_static_member_with_the_class_name_1_0, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg), symbolToString(symbol));
+                            error(errorLocation, Diagnostics.Cannot_find_name_0_Did_you_mean_the_static_member_1_0, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg), symbolToString(symbol));
                             return true;
                         }
                     }
@@ -801,7 +801,7 @@ namespace ts {
                         if (location === container) {
                             classType = (<InterfaceType>getDeclaredTypeOfSymbol(symbol)).thisType;
                             if (getPropertyOfType(classType, name)) {
-                                error(errorLocation, Diagnostics.Cannot_find_name_0_Did_you_mean_to_prefix_the_object_member_with_this_this_0, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
+                                error(errorLocation, Diagnostics.Cannot_find_name_0_Did_you_mean_the_instance_member_this_0, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
                                 return true;
                             }
                         }
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 7f1c195ae20..0453df0a9bf 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -1775,11 +1775,11 @@
         "category": "Error",
         "code": 2661
     },
-    "Cannot find name '{0}'. Did you mean to prefix the static member with the class name, '{1}.{0}'?": {
+    "Cannot find name '{0}'. Did you mean the static member '{1}.{0}'?": {
         "category": "Error",
         "code": 2662
     },
-    "Cannot find name '{0}'. Did you mean to prefix the object member with 'this', 'this.{0}'?": {
+    "Cannot find name '{0}'. Did you mean the instance member 'this.{0}'?": {
         "category": "Error",
         "code": 2663
     },
diff --git a/tests/baselines/reference/YieldExpression11_es6.errors.txt b/tests/baselines/reference/YieldExpression11_es6.errors.txt
index 4a2f93a9c6d..1b0c08bd79a 100644
--- a/tests/baselines/reference/YieldExpression11_es6.errors.txt
+++ b/tests/baselines/reference/YieldExpression11_es6.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(2,3): error TS1220: Generators are only available when targeting ECMAScript 6 or higher.
-tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(3,11): error TS2663: Cannot find name 'foo'. Did you mean to prefix the object member with 'this', 'this.foo'?
+tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(3,11): error TS2663: Cannot find name 'foo'. Did you mean the instance member 'this.foo'?
 
 
 ==== tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts (2 errors) ====
@@ -9,6 +9,6 @@ tests/cases/conformance/es6/yieldExpressions/YieldExpression11_es6.ts(3,11): err
 !!! error TS1220: Generators are only available when targeting ECMAScript 6 or higher.
         yield(foo);
               ~~~
-!!! error TS2663: Cannot find name 'foo'. Did you mean to prefix the object member with 'this', 'this.foo'?
+!!! error TS2663: Cannot find name 'foo'. Did you mean the instance member 'this.foo'?
       }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt b/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt
index 03e4e83e409..eb6744d656b 100644
--- a/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt
+++ b/tests/baselines/reference/initializerReferencingConstructorParameters.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(4,9): error TS2304: Cannot find name 'x'.
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(5,15): error TS2304: Cannot find name 'x'.
-tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(10,9): error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
+tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(10,9): error TS2663: Cannot find name 'x'. Did you mean the instance member 'this.x'?
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(11,15): error TS2304: Cannot find name 'x'.
 tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(17,15): error TS1003: Identifier expected.
-tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(23,9): error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
+tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts(23,9): error TS2663: Cannot find name 'x'. Did you mean the instance member 'this.x'?
 
 
 ==== tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencingConstructorParameters.ts (6 errors) ====
@@ -22,7 +22,7 @@ tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencin
     class D {
         a = x; // error
             ~
-!!! error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
+!!! error TS2663: Cannot find name 'x'. Did you mean the instance member 'this.x'?
         b: typeof x; // error
                   ~
 !!! error TS2304: Cannot find name 'x'.
@@ -41,6 +41,6 @@ tests/cases/conformance/classes/propertyMemberDeclarations/initializerReferencin
         a = this.x; // ok
         b = x; // error
             ~
-!!! error TS2663: Cannot find name 'x'. Did you mean to prefix the object member with 'this', 'this.x'?
+!!! error TS2663: Cannot find name 'x'. Did you mean the instance member 'this.x'?
         constructor(public x: T) { }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserharness.errors.txt b/tests/baselines/reference/parserharness.errors.txt
index 711d3fd9aac..963ce12ddf1 100644
--- a/tests/baselines/reference/parserharness.errors.txt
+++ b/tests/baselines/reference/parserharness.errors.txt
@@ -7,11 +7,11 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(25,17): er
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(41,12): error TS2304: Cannot find name 'ActiveXObject'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(43,19): error TS2304: Cannot find name 'require'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(44,14): error TS2304: Cannot find name 'require'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(341,13): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(347,13): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(351,17): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,17): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,35): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(341,13): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(347,13): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(351,17): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,17): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(354,35): error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(691,50): error TS2304: Cannot find name 'ITextWriter'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(716,47): error TS2503: Cannot find namespace 'TypeScript'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(721,62): error TS2304: Cannot find name 'ITextWriter'.
@@ -471,7 +471,7 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(2030,32):
             static pushGlobalErrorHandler(done: IDone) {
                 errorHandlerStack.push(function (e) {
                 ~~~~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
                     done(e);
                 });
             }
@@ -479,20 +479,20 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserharness.ts(2030,32):
             static popGlobalErrorHandler() {
                 errorHandlerStack.pop();
                 ~~~~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
             }
     
             static handleError(e: Error) {
                 if (errorHandlerStack.length === 0) {
                     ~~~~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
                     IO.printLine('Global error: ' + e);
                 } else {
                     errorHandlerStack[errorHandlerStack.length - 1](e);
                     ~~~~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
                                       ~~~~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean to prefix the static member with the class name, 'Runnable.errorHandlerStack'?
+!!! error TS2662: Cannot find name 'errorHandlerStack'. Did you mean the static member 'Runnable.errorHandlerStack'?
                 }
             }
         }
diff --git a/tests/baselines/reference/parserindenter.errors.txt b/tests/baselines/reference/parserindenter.errors.txt
index d892f27579f..8ccc9220710 100644
--- a/tests/baselines/reference/parserindenter.errors.txt
+++ b/tests/baselines/reference/parserindenter.errors.txt
@@ -28,7 +28,7 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(152,63):
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(153,30): error TS2304: Cannot find name 'List_TextEditInfo'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(155,32): error TS2304: Cannot find name 'AuthorTokenKind'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(182,79): error TS2503: Cannot find namespace 'Services'.
-tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(183,20): error TS2662: Cannot find name 'GetIndentSizeFromText'. Did you mean to prefix the static member with the class name, 'Indenter.GetIndentSizeFromText'?
+tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(183,20): error TS2662: Cannot find name 'GetIndentSizeFromText'. Did you mean the static member 'Indenter.GetIndentSizeFromText'?
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(186,67): error TS2503: Cannot find namespace 'Services'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(207,50): error TS2304: Cannot find name 'TokenSpan'.
 tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(207,67): error TS2304: Cannot find name 'ParseNode'.
@@ -373,7 +373,7 @@ tests/cases/conformance/parser/ecmascript5/RealWorld/parserindenter.ts(736,38):
 !!! error TS2503: Cannot find namespace 'Services'.
                 return GetIndentSizeFromText(indentText, editorOptions, /*includeNonIndentChars:*/ false);
                        ~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'GetIndentSizeFromText'. Did you mean to prefix the static member with the class name, 'Indenter.GetIndentSizeFromText'?
+!!! error TS2662: Cannot find name 'GetIndentSizeFromText'. Did you mean the static member 'Indenter.GetIndentSizeFromText'?
             }
     
             static GetIndentSizeFromText(text: string, editorOptions: Services.EditorOptions, includeNonIndentChars: boolean): number {
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.errors.txt b/tests/baselines/reference/recursiveClassReferenceTest.errors.txt
index 76563a19b5a..4a1a6f1782c 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.errors.txt
+++ b/tests/baselines/reference/recursiveClassReferenceTest.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/compiler/recursiveClassReferenceTest.ts(16,19): error TS2304: Cannot find name 'Element'.
-tests/cases/compiler/recursiveClassReferenceTest.ts(56,11): error TS2663: Cannot find name 'domNode'. Did you mean to prefix the object member with 'this', 'this.domNode'?
-tests/cases/compiler/recursiveClassReferenceTest.ts(88,36): error TS2663: Cannot find name 'mode'. Did you mean to prefix the object member with 'this', 'this.mode'?
+tests/cases/compiler/recursiveClassReferenceTest.ts(56,11): error TS2663: Cannot find name 'domNode'. Did you mean the instance member 'this.domNode'?
+tests/cases/compiler/recursiveClassReferenceTest.ts(88,36): error TS2663: Cannot find name 'mode'. Did you mean the instance member 'this.mode'?
 tests/cases/compiler/recursiveClassReferenceTest.ts(95,21): error TS2345: Argument of type 'Window' is not assignable to parameter of type 'IMode'.
   Property 'getInitialState' is missing in type 'Window'.
 
@@ -65,7 +65,7 @@ tests/cases/compiler/recursiveClassReferenceTest.ts(95,21): error TS2345: Argume
     		public getDomNode() {
     			return domNode;
     			       ~~~~~~~
-!!! error TS2663: Cannot find name 'domNode'. Did you mean to prefix the object member with 'this', 'this.domNode'?
+!!! error TS2663: Cannot find name 'domNode'. Did you mean the instance member 'this.domNode'?
     		}
     		
     		public destroy() {
@@ -99,7 +99,7 @@ tests/cases/compiler/recursiveClassReferenceTest.ts(95,21): error TS2345: Argume
     		
     		public getMode(): IMode { return mode; }
     		                                 ~~~~
-!!! error TS2663: Cannot find name 'mode'. Did you mean to prefix the object member with 'this', 'this.mode'?
+!!! error TS2663: Cannot find name 'mode'. Did you mean the instance member 'this.mode'?
     	}
     	
     	export class Mode extends AbstractMode {
diff --git a/tests/baselines/reference/scannertest1.errors.txt b/tests/baselines/reference/scannertest1.errors.txt
index 234923b5a2f..3831dbe398e 100644
--- a/tests/baselines/reference/scannertest1.errors.txt
+++ b/tests/baselines/reference/scannertest1.errors.txt
@@ -1,14 +1,14 @@
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(1,1): error TS6053: File 'tests/cases/conformance/scanner/ecmascript5/References.ts' not found.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(5,21): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(5,47): error TS2304: Cannot find name 'CharacterCodes'.
-tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(9,16): error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
+tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(9,16): error TS2662: Cannot find name 'isDecimalDigit'. Did you mean the static member 'CharacterInfo.isDecimalDigit'?
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(10,22): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(10,47): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(11,22): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(11,47): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(15,9): error TS2304: Cannot find name 'Debug'.
-tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(15,22): error TS2662: Cannot find name 'isHexDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isHexDigit'?
-tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(16,16): error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
+tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(15,22): error TS2662: Cannot find name 'isHexDigit'. Did you mean the static member 'CharacterInfo.isHexDigit'?
+tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(16,16): error TS2662: Cannot find name 'isDecimalDigit'. Did you mean the static member 'CharacterInfo.isDecimalDigit'?
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(17,20): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(18,21): error TS2304: Cannot find name 'CharacterCodes'.
 tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(18,46): error TS2304: Cannot find name 'CharacterCodes'.
@@ -33,7 +33,7 @@ tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(20,23): error TS2304
         public static isHexDigit(c: number): boolean {
             return isDecimalDigit(c) ||
                    ~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
+!!! error TS2662: Cannot find name 'isDecimalDigit'. Did you mean the static member 'CharacterInfo.isDecimalDigit'?
                    (c >= CharacterCodes.A && c <= CharacterCodes.F) ||
                          ~~~~~~~~~~~~~~
 !!! error TS2304: Cannot find name 'CharacterCodes'.
@@ -51,10 +51,10 @@ tests/cases/conformance/scanner/ecmascript5/scannertest1.ts(20,23): error TS2304
             ~~~~~
 !!! error TS2304: Cannot find name 'Debug'.
                          ~~~~~~~~~~
-!!! error TS2662: Cannot find name 'isHexDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isHexDigit'?
+!!! error TS2662: Cannot find name 'isHexDigit'. Did you mean the static member 'CharacterInfo.isHexDigit'?
             return isDecimalDigit(c)
                    ~~~~~~~~~~~~~~
-!!! error TS2662: Cannot find name 'isDecimalDigit'. Did you mean to prefix the static member with the class name, 'CharacterInfo.isDecimalDigit'?
+!!! error TS2662: Cannot find name 'isDecimalDigit'. Did you mean the static member 'CharacterInfo.isDecimalDigit'?
                 ? (c - CharacterCodes._0)
                        ~~~~~~~~~~~~~~
 !!! error TS2304: Cannot find name 'CharacterCodes'.
diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt
index d8fbf512bcd..91cb87dbeb8 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(4,7): error TS2663: Cannot find name 'v'. Did you mean to prefix the object member with 'this', 'this.v'?
+tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(4,7): error TS2663: Cannot find name 'v'. Did you mean the instance member 'this.v'?
 tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(6,7): error TS2304: Cannot find name 's'.
 
 
@@ -8,7 +8,7 @@ tests/cases/compiler/scopeCheckExtendedClassInsidePublicMethod2.ts(6,7): error T
        public c() {
           v = 1;
           ~
-!!! error TS2663: Cannot find name 'v'. Did you mean to prefix the object member with 'this', 'this.v'?
+!!! error TS2663: Cannot find name 'v'. Did you mean the instance member 'this.v'?
           this.p = 1;
           s = 1;
           ~
diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt
index ac9381272e8..dd3e5ef446b 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(4,7): error TS2304: Cannot find name 'v'.
 tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(5,12): error TS2339: Property 'p' does not exist on type 'typeof D'.
-tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(6,7): error TS2662: Cannot find name 's'. Did you mean to prefix the static member with the class name, 'D.s'?
+tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(6,7): error TS2662: Cannot find name 's'. Did you mean the static member 'D.s'?
 
 
 ==== tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts (3 errors) ====
@@ -15,6 +15,6 @@ tests/cases/compiler/scopeCheckExtendedClassInsideStaticMethod1.ts(6,7): error T
 !!! error TS2339: Property 'p' does not exist on type 'typeof D'.
           s = 1;
           ~
-!!! error TS2662: Cannot find name 's'. Did you mean to prefix the static member with the class name, 'D.s'?
+!!! error TS2662: Cannot find name 's'. Did you mean the static member 'D.s'?
        }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt b/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt
index 190ea245459..4152c182d45 100644
--- a/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt
+++ b/tests/baselines/reference/unqualifiedCallToClassStatic1.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/unqualifiedCallToClassStatic1.ts(4,3): error TS2662: Cannot find name 'foo'. Did you mean to prefix the static member with the class name, 'Vector.foo'?
+tests/cases/compiler/unqualifiedCallToClassStatic1.ts(4,3): error TS2662: Cannot find name 'foo'. Did you mean the static member 'Vector.foo'?
 
 
 ==== tests/cases/compiler/unqualifiedCallToClassStatic1.ts (1 errors) ====
@@ -7,6 +7,6 @@ tests/cases/compiler/unqualifiedCallToClassStatic1.ts(4,3): error TS2662: Cannot
       // 'foo' cannot be called in an unqualified manner.
       foo();
       ~~~
-!!! error TS2662: Cannot find name 'foo'. Did you mean to prefix the static member with the class name, 'Vector.foo'?
+!!! error TS2662: Cannot find name 'foo'. Did you mean the static member 'Vector.foo'?
      }
     }
\ No newline at end of file

From dbfe862dbd87e491728fdd83c82c26572c63af7b Mon Sep 17 00:00:00 2001
From: Zhengbo Li <zhengbli@microsoft.com>
Date: Thu, 14 Jan 2016 00:34:43 -0800
Subject: [PATCH 27/28] not casting relative filenames in 'tsc watch' to Path

---
 src/compiler/core.ts         | 7 +++++++
 src/compiler/sys.ts          | 6 +++---
 src/compiler/tsc.ts          | 6 ++++--
 src/server/editorServices.ts | 4 ++--
 src/services/services.ts     | 7 -------
 5 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index aba2e48e4a1..639660a2a4c 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -872,4 +872,11 @@ namespace ts {
         }
         return copiedList;
     }
+
+    export function createGetCanonicalFileName(useCaseSensitivefileNames: boolean): (fileName: string) => string {
+        return useCaseSensitivefileNames
+            ? ((fileName) => fileName)
+            : ((fileName) => fileName.toLowerCase());
+    }
+
 }
diff --git a/src/compiler/sys.ts b/src/compiler/sys.ts
index 073a662ce1c..e6f908d250a 100644
--- a/src/compiler/sys.ts
+++ b/src/compiler/sys.ts
@@ -11,7 +11,7 @@ namespace ts {
         write(s: string): void;
         readFile(path: string, encoding?: string): string;
         writeFile(path: string, data: string, writeByteOrderMark?: boolean): void;
-        watchFile?(path: string, callback: FileWatcherCallback): FileWatcher;
+        watchFile?(path: Path, callback: FileWatcherCallback): FileWatcher;
         watchDirectory?(path: string, callback: DirectoryWatcherCallback, recursive?: boolean): FileWatcher;
         resolvePath(path: string): string;
         fileExists(path: string): boolean;
@@ -500,13 +500,13 @@ namespace ts {
                 },
                 readFile,
                 writeFile,
-                watchFile: (fileName, callback) => {
+                watchFile: (filePath, callback) => {
                     // Node 4.0 stablized the `fs.watch` function on Windows which avoids polling
                     // and is more efficient than `fs.watchFile` (ref: https://github.com/nodejs/node/pull/2649
                     // and https://github.com/Microsoft/TypeScript/issues/4643), therefore
                     // if the current node.js version is newer than 4, use `fs.watch` instead.
                     const watchSet = isNode4OrLater() ? watchedFileSet : pollingWatchedFileSet;
-                    const watchedFile =  watchSet.addFile(<Path>fileName, callback);
+                    const watchedFile =  watchSet.addFile(filePath, callback);
                     return {
                         close: () => watchSet.removeFile(watchedFile)
                     };
diff --git a/src/compiler/tsc.ts b/src/compiler/tsc.ts
index d064ec54c9c..808ee6da804 100644
--- a/src/compiler/tsc.ts
+++ b/src/compiler/tsc.ts
@@ -334,7 +334,8 @@ namespace ts {
                 return sys.exit(ExitStatus.DiagnosticsPresent_OutputsSkipped);
             }
             if (configFileName) {
-                configFileWatcher = sys.watchFile(configFileName, configFileChanged);
+                const configFilePath = toPath(configFileName, sys.getCurrentDirectory(), createGetCanonicalFileName(sys.useCaseSensitiveFileNames));
+                configFileWatcher = sys.watchFile(configFilePath, configFileChanged);
             }
             if (sys.watchDirectory && configFileName) {
                 const directory = ts.getDirectoryPath(configFileName);
@@ -442,7 +443,8 @@ namespace ts {
             const sourceFile = hostGetSourceFile(fileName, languageVersion, onError);
             if (sourceFile && compilerOptions.watch) {
                 // Attach a file watcher
-                sourceFile.fileWatcher = sys.watchFile(sourceFile.fileName, (fileName: string, removed?: boolean) => sourceFileChanged(sourceFile, removed));
+                const filePath = toPath(sourceFile.fileName, sys.getCurrentDirectory(), createGetCanonicalFileName(sys.useCaseSensitiveFileNames));
+                sourceFile.fileWatcher = sys.watchFile(filePath, (fileName: string, removed?: boolean) => sourceFileChanged(sourceFile, removed));
             }
             return sourceFile;
         }
diff --git a/src/server/editorServices.ts b/src/server/editorServices.ts
index 5a1c85fc13c..0442575aded 100644
--- a/src/server/editorServices.ts
+++ b/src/server/editorServices.ts
@@ -1000,7 +1000,7 @@ namespace ts.server {
                     info.setFormatOptions(this.getFormatCodeOptions());
                     this.filenameToScriptInfo[fileName] = info;
                     if (!info.isOpen) {
-                        info.fileWatcher = this.host.watchFile(fileName, _ => { this.watchedFileChanged(fileName); });
+                        info.fileWatcher = this.host.watchFile(<Path>fileName, _ => { this.watchedFileChanged(fileName); });
                     }
                 }
             }
@@ -1213,7 +1213,7 @@ namespace ts.server {
                     }
                 }
                 project.finishGraph();
-                project.projectFileWatcher = this.host.watchFile(configFilename, _ => this.watchedProjectConfigFileChanged(project));
+                project.projectFileWatcher = this.host.watchFile(<Path>configFilename, _ => this.watchedProjectConfigFileChanged(project));
                 this.log("Add recursive watcher for: " + ts.getDirectoryPath(configFilename));
                 project.directoryWatcher = this.host.watchDirectory(
                     ts.getDirectoryPath(configFilename),
diff --git a/src/services/services.ts b/src/services/services.ts
index 0ffd1138cba..0f3c18f7a85 100644
--- a/src/services/services.ts
+++ b/src/services/services.ts
@@ -2008,13 +2008,6 @@ namespace ts {
         return createLanguageServiceSourceFile(sourceFile.fileName, scriptSnapshot, sourceFile.languageVersion, version, /*setNodeParents*/ true);
     }
 
-    export function createGetCanonicalFileName(useCaseSensitivefileNames: boolean): (fileName: string) => string {
-        return useCaseSensitivefileNames
-            ? ((fileName) => fileName)
-            : ((fileName) => fileName.toLowerCase());
-    }
-
-
     export function createDocumentRegistry(useCaseSensitiveFileNames?: boolean, currentDirectory = ""): DocumentRegistry {
         // Maps from compiler setting target (ES3, ES5, etc.) to all the cached documents we have
         // for those settings.

From e547a1abd27586b41ce7285afe0fadbbf4314e34 Mon Sep 17 00:00:00 2001
From: Ryan Cavanaugh <RyanCavanaugh@users.noreply.github.com>
Date: Thu, 14 Jan 2016 11:30:02 -0800
Subject: [PATCH 28/28] Update CONTRIBUTING.md

Add guidelines for logging issues
---
 CONTRIBUTING.md | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 3a712b5619a..d9941d92e87 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,3 +1,45 @@
+# Instructions for Logging Issues
+
+## 1. Read the FAQ
+
+Please [read the FAQ](https://github.com/Microsoft/TypeScript/wiki/FAQ) before logging new issues, even if you think you have found a bug.
+
+Issues that ask questions answered in the FAQ will be closed without elaboration.
+
+## 2. Search for Duplicates
+
+[Search the existing issues](https://github.com/Microsoft/TypeScript/issues?utf8=%E2%9C%93&q=is%3Aissue) before logging a new one.
+
+## 3. Do you have a question?
+
+The issue tracker is for **issues**, in other words, bugs and suggestions.
+If you have a *question*, please use [http://stackoverflow.com/questions/tagged/typescript](Stack Overflow), [https://gitter.im/Microsoft/TypeScript](Gitter), your favorite search engine, or other resources.
+Due to increased traffic, we can no longer answer questions in the issue tracker.
+
+## 4. Did you find a bug?
+
+When logging a bug, please be sure to include the following:
+ * What version of TypeScript you're using (run `tsc --v`)
+ * If at all possible, an *isolated* way to reproduce the behavior
+ * The behavior you expect to see, and the actual behavior
+
+You can try out the nightly build of TypeScript (`npm install typescript@next`) to see if the bug has already been fixed.
+
+## 5. Do you have a suggestion?
+
+We also accept suggestions in the issue tracker.
+Be sure to [check the FAQ](https://github.com/Microsoft/TypeScript/wiki/FAQ) and [search](https://github.com/Microsoft/TypeScript/issues?utf8=%E2%9C%93&q=is%3Aissue) first.
+
+In general, things we find useful when reviewing suggestins are:
+* A description of the problem you're trying to solve
+* An overview of the suggested solution
+* Examples of how the suggestion would work in various places
+  * Code examples showing e.g. "this would be an error, this wouldn't"
+  * Code examples showing the generated JavaScript (if applicable)
+* If relevant, precedent in other languages can be useful for establishing context and expected behavior
+
+# Instructions for Contributing Code
+
 ## Contributing bug fixes
 
 TypeScript is currently accepting contributions in the form of bug fixes. A bug must have an issue tracking it in the issue tracker that has been approved ("Milestone == Community") by the TypeScript team. Your pull request should include a link to the bug that you are fixing. If you've submitted a PR for a bug, please post a comment in the bug to avoid duplication of effort.