Migrating File Watching Functionality from Chokidar to VSCode FileSystemWatcher API (#4710)

* migrated vscode fileSystemWatcher and got rid of chokidar

* fixing lockfile

---------

Co-authored-by: Hannia Valera <[email protected]>

Author: hanniavalera

CHANGELOG.md

@@ -10,6 +10,7 @@ Improvements:
 - Add MSVC linker error problem matching to the Problems pane. [#4675](https://github.com/microsoft/vscode-cmake-tools/pull/4675) [@bradphelan](https://github.com/bradphelan)
 
 Bug Fixes:
+- Fix spurious preset reloads triggered by unrelated file system events such as builds, git commits, and `cmake.copyCompileCommands`. Migrated file watching from chokidar to VS Code's built-in `FileSystemWatcher` API, which also resolves high CPU usage on Apple M1. [#4703](https://github.com/microsoft/vscode-cmake-tools/issues/4703) [#2967](https://github.com/microsoft/vscode-cmake-tools/issues/2967)
 - Clarify that semicolons in `cmake.configureSettings` string values are escaped, and array notation should be used for CMake lists. [#4585](https://github.com/microsoft/vscode-cmake-tools/issues/4585)
 - Fix "CMake: Quick Start" command failing silently when no folder is open. Now shows an error message with an option to open a folder. [#4504](https://github.com/microsoft/vscode-cmake-tools/issues/4504)
 - Fix "CMake: Run Without Debugging" not changing the working directory when the build directory changes. [#4549](https://github.com/microsoft/vscode-cmake-tools/issues/4549)

package.json

@@ -4025,7 +4025,6 @@
     "@friedemannsommer/lcov-parser": "^5.0.0",
     "@types/string.prototype.matchall": "^4.0.4",
     "ajv": "^7.1.0",
-    "chokidar": "^3.5.1",
     "handlebars": "^4.7.7",
     "iconv-lite": "^0.6.2",
     "js-yaml": "^4.1.1",
@@ -4047,7 +4046,6 @@
   },
   "resolutions": {
     "ansi-regex": "^5.0.1",
-    "chokidar": "^3.5.1",
     "glob-parent": "^6.0.2",
     "hosted-git-info": "^3.0.8",
     "**/minimist": "^1.2.5",

src/extension.ts

@@ -5,7 +5,6 @@
 
 'use strict';
 
-import * as chokidar from 'chokidar';
 import * as path from 'path';
 import * as vscode from 'vscode';
 import * as cpt from 'vscode-cpptools';
@@ -676,7 +675,7 @@ export class ExtensionManager implements vscode.Disposable {
             )
         );
         this.onDidChangeActiveTextEditorSub.dispose();
-        void this.kitsWatcher.close();
+        void this.kitsWatcher.dispose();
         this.projectOutlineTreeView.dispose();
         this.bookmarksTreeView.dispose();
         this.extensionActiveCommandsEmitter.dispose();
@@ -997,9 +996,16 @@ export class ExtensionManager implements vscode.Disposable {
     /**
      * Watches for changes to the kits file
      */
-    private readonly kitsWatcher = util.chokidarOnAnyChange(
-        chokidar.watch(USER_KITS_FILEPATH, { ignoreInitial: true }),
-        _ => rollbar.takePromise(localize('rereading.kits', 'Re-reading kits'), {}, KitsController.readUserKits(this.getActiveProject())));
+    private readonly kitsWatcher: vscode.FileSystemWatcher = (() => {
+        const dirUri = vscode.Uri.file(path.dirname(USER_KITS_FILEPATH));
+        const pattern = new vscode.RelativePattern(dirUri, path.basename(USER_KITS_FILEPATH));
+        const watcher = vscode.workspace.createFileSystemWatcher(pattern);
+        const rereadHandler = () => rollbar.takePromise(localize('rereading.kits', 'Re-reading kits'), {}, KitsController.readUserKits(this.getActiveProject()));
+        watcher.onDidChange(rereadHandler);
+        watcher.onDidCreate(rereadHandler);
+        watcher.onDidDelete(rereadHandler);
+        return watcher;
+    })();
 
     /**
      * Opens a text editor with the user-local `cmake-kits.json` file.

src/kits/kitsController.ts

@@ -1,6 +1,5 @@
 'use strict';
 
-import * as chokidar from 'chokidar';
 import * as path from 'path';
 import * as vscode from 'vscode';
 import * as nls from 'vscode-nls';
@@ -22,7 +21,7 @@ import * as logging from '@cmt/logging';
 import paths from '@cmt/paths';
 import { fs } from '@cmt/pr';
 import rollbar from '@cmt/rollbar';
-import { chokidarOnAnyChange, ProgressHandle, reportProgress } from '@cmt/util';
+import { ProgressHandle, reportProgress } from '@cmt/util';
 import { ConfigurationType } from 'vscode-cmake-tools';
 
 nls.config({ messageFormat: nls.MessageFormat.bundle, bundleFormat: nls.BundleFormat.standalone })();
@@ -57,7 +56,7 @@ export class KitsController {
     folderKits: Kit[] = [];
     additionalKits: Kit[] = [];
 
-    private constructor(readonly project: CMakeProject, private readonly _kitsWatcher: chokidar.FSWatcher) {}
+    private constructor(readonly project: CMakeProject, private readonly _kitsWatchers: vscode.Disposable[]) {}
 
     static async init(project: CMakeProject) {
         if (KitsController.userKits.length === 0) {
@@ -67,10 +66,20 @@ export class KitsController {
 
         const expandedAdditionalKitFiles: string[] = await project.getExpandedAdditionalKitFiles();
         const folderKitsFiles: string[] = [KitsController._workspaceKitsPath(project.workspaceFolder)].concat(expandedAdditionalKitFiles);
-        const kitsWatcher = chokidar.watch(folderKitsFiles, { ignoreInitial: true, followSymlinks: false });
-        const kitsController = new KitsController(project, kitsWatcher);
-        chokidarOnAnyChange(kitsWatcher, _ => rollbar.takePromise(localize('rereading.kits', 'Re-reading folder kits'), {},
-            kitsController.readKits(KitsReadMode.folderKits)));
+
+        const kitsWatchers: vscode.Disposable[] = [];
+        const kitsController = new KitsController(project, kitsWatchers);
+        const rereadHandler = () => rollbar.takePromise(localize('rereading.kits', 'Re-reading folder kits'), {},
+            kitsController.readKits(KitsReadMode.folderKits));
+        for (const kitFile of folderKitsFiles) {
+            const dirUri = vscode.Uri.file(path.dirname(kitFile));
+            const pattern = new vscode.RelativePattern(dirUri, path.basename(kitFile));
+            const watcher = vscode.workspace.createFileSystemWatcher(pattern);
+            watcher.onDidChange(rereadHandler);
+            watcher.onDidCreate(rereadHandler);
+            watcher.onDidDelete(rereadHandler);
+            kitsWatchers.push(watcher);
+        }
         project.workspaceContext.config.onChange('additionalKits', () => kitsController.readKits(KitsReadMode.folderKits));
 
         await kitsController.readKits(KitsReadMode.folderKits);
@@ -81,7 +90,9 @@ export class KitsController {
         if (this._pickKitCancellationTokenSource) {
             this._pickKitCancellationTokenSource.dispose();
         }
-        void this._kitsWatcher.close();
+        for (const watcher of this._kitsWatchers) {
+            watcher.dispose();
+        }
     }
 
     get availableKits() {

src/kits/variant.ts

@@ -1,5 +1,4 @@
 import * as ajv from 'ajv';
-import * as chokidar from 'chokidar';
 import * as yaml from 'js-yaml';
 import * as json5 from 'json5';
 import * as path from 'path';
@@ -192,7 +191,7 @@ export class VariantManager implements vscode.Disposable {
     /**
      * Watches for changes to the variants file on the filesystem
      */
-    private readonly _variantFileWatcher = chokidar.watch([], { ignoreInitial: true, followSymlinks: false });
+    private readonly _variantFileWatchers: vscode.Disposable[] = [];
     private customVariantsFileExists: boolean = false;
 
     /**
@@ -201,7 +200,9 @@ export class VariantManager implements vscode.Disposable {
     private initialized: boolean = false;
 
     dispose() {
-        void this._variantFileWatcher.close();
+        for (const watcher of this._variantFileWatchers) {
+            watcher.dispose();
+        }
         this._activeVariantChanged.dispose();
     }
 
@@ -215,15 +216,19 @@ export class VariantManager implements vscode.Disposable {
             return;  // Nothing we can do. We have no directory open
         }
         // Ref: https://code.visualstudio.com/api/references/vscode-api#Uri
-        for (const filename of ['cmake-variants.yaml',
-            'cmake-variants.json',
-            '.vscode/cmake-variants.yaml',
-            '.vscode/cmake-variants.json']) {
-            this._variantFileWatcher.add(path.join(workspaceFolder.uri.fsPath, filename));
-        }
-        util.chokidarOnAnyChange(
-            this._variantFileWatcher,
-            filePath => rollbar.invokeAsync(localize('reloading.variants.file', 'Reloading variants file {0}', filePath), () => this._reloadVariantsFile(filePath)));
+        const variantGlob = new vscode.RelativePattern(
+            workspaceFolder,
+            '{cmake-variants.yaml,cmake-variants.json,.vscode/cmake-variants.yaml,.vscode/cmake-variants.json}'
+        );
+        const variantWatcher = vscode.workspace.createFileSystemWatcher(variantGlob);
+        const reloadHandler = (uri: vscode.Uri) => rollbar.invokeAsync(
+            localize('reloading.variants.file', 'Reloading variants file {0}', uri.fsPath),
+            () => this._reloadVariantsFile(uri.fsPath)
+        );
+        variantWatcher.onDidChange(reloadHandler);
+        variantWatcher.onDidCreate(reloadHandler);
+        variantWatcher.onDidDelete(reloadHandler);
+        this._variantFileWatchers.push(variantWatcher);
 
         config.onChange('defaultVariants', () => {
             rollbar.invokeAsync(localize('reloading.variants.from.settings', 'Reloading variants from settings'), () => this._reloadVariantsFile());

src/presets/presetsController.ts

@@ -1,4 +1,3 @@
-import * as chokidar from 'chokidar';
 import * as path from 'path';
 import * as vscode from 'vscode';
 import * as nls from 'vscode-nls';
@@ -1605,14 +1604,8 @@ export class PresetsController implements vscode.Disposable {
             void this.onCreatePresetsFile();
         };
 
-        const events: Map<string, () => void> = new Map<string, () => void>([
-            ["change", presetChangeHandler],
-            ["unlink", presetChangeHandler],
-            ["add", presetCreatedHandler]
-        ]);
-
         this._presetsWatchers?.dispose();
-        this._presetsWatchers = new FileWatcher(this._referencedFiles, events, { ignoreInitial: true, followSymlinks: false });
+        this._presetsWatchers = new FileWatcher(this._referencedFiles, presetChangeHandler, presetCreatedHandler);
     };
 
     dispose() {
@@ -1625,72 +1618,47 @@ export class PresetsController implements vscode.Disposable {
 }
 
 /**
- * FileWatcher is a wrapper around chokidar's FSWatcher that allows for watching multiple paths.
- * Chokidar's support for watching multiple paths is currently broken, if it is fixed in the future, this class can be removed.
+ * FileWatcher watches an array of specific file paths using VS Code's built-in
+ * vscode.workspace.createFileSystemWatcher API. This replaces the previous chokidar-based
+ * implementation to eliminate spurious preset reloads triggered by unrelated file system
+ * events (builds, git commits, copyCompileCommands). See issues #4703 and #2967.
  */
 class FileWatcher implements vscode.Disposable {
-    private watchers: Map<string, chokidar.FSWatcher>;
-    // Debounce the change handler to avoid multiple changes being triggered by a single file change. Two change events are coming in rapid succession without this.
+    private watchers: vscode.Disposable[] = [];
+    // Debounce the change handler to avoid multiple changes being triggered by a single file change.
+    // Two change events are coming in rapid succession without this.
     private canRunChangeHandler = true;
-    // Grace period flag to ignore events during watcher startup. When followSymlinks is false and
-    // watched files are symlinks, chokidar may emit spurious events during initialization that
-    // bypass ignoreInitial. This prevents infinite loops when reapplyPresets() recreates the watcher.
-    // See issue #4668.
-    private isInStartupGracePeriod = true;
-
-    public constructor(paths: string | string[], eventHandlers: Map<string, () => void>, options?: chokidar.WatchOptions) {
-        this.watchers = new Map<string, chokidar.FSWatcher>();
-
-        // Allow a short grace period for the watcher to stabilize before processing events.
-        // This handles the case where symlinks cause spurious events during watcher setup.
-        // See issue #4668.
-        setTimeout(() => (this.isInStartupGracePeriod = false), 100);
-
-        // Wrap all event handlers to respect the startup grace period
-        const wrappedHandlers = new Map<string, () => void>();
-        for (const [event, handler] of eventHandlers) {
-            if (event === 'change') {
-                // Change events get additional debouncing to avoid multiple changes
-                // being triggered by a single file change
-                const debouncedOnChange = () => {
-                    if (this.isInStartupGracePeriod) {
-                        return; // Ignore events during startup grace period
-                    }
-                    if (this.canRunChangeHandler) {
-                        handler();
-                        this.canRunChangeHandler = false;
-                        setTimeout(() => (this.canRunChangeHandler = true), 500);
-                    }
-                };
-                wrappedHandlers.set(event, debouncedOnChange);
-            } else {
-                // Other events just respect the grace period
-                const wrappedHandler = () => {
-                    if (this.isInStartupGracePeriod) {
-                        return; // Ignore events during startup grace period
-                    }
-                    handler();
-                };
-                wrappedHandlers.set(event, wrappedHandler);
+
+    public constructor(filePaths: string[], changeHandler: () => void, createHandler: () => void) {
+        const debouncedOnChange = () => {
+            if (this.canRunChangeHandler) {
+                changeHandler();
+                this.canRunChangeHandler = false;
+                setTimeout(() => (this.canRunChangeHandler = true), 500);
             }
-        }
+        };
 
-        for (const path of Array.isArray(paths) ? paths : [paths]) {
+        for (const filePath of filePaths) {
             try {
-                const watcher = chokidar.watch(path, { ...options });
-                for (const [event, handler] of wrappedHandlers) {
-                    watcher.on(event, handler);
-                }
-                this.watchers.set(path, watcher);
+                const dirUri = vscode.Uri.file(path.dirname(filePath));
+                const pattern = new vscode.RelativePattern(dirUri, path.basename(filePath));
+                const watcher = vscode.workspace.createFileSystemWatcher(pattern);
+
+                watcher.onDidChange(debouncedOnChange);
+                watcher.onDidCreate(createHandler);
+                watcher.onDidDelete(debouncedOnChange);
+
+                this.watchers.push(watcher);
             } catch (error) {
-                log.error(localize('failed.to.watch', 'Watcher could not be created for {0}: {1}', path, util.errorToString(error)));
+                log.error(localize('failed.to.watch', 'Watcher could not be created for {0}: {1}', filePath, util.errorToString(error)));
             }
         }
     }
 
     public dispose() {
-        for (const watcher of this.watchers.values()) {
-            watcher.close().then(() => {}, () => {});
+        for (const watcher of this.watchers) {
+            watcher.dispose();
         }
+        this.watchers = [];
     }
 }

src/util.ts

@@ -1,5 +1,4 @@
 import * as child_process from 'child_process';
-import * as chokidar from 'chokidar';
 import * as fs from 'fs';
 import * as path from 'path';
 import * as vscode from 'vscode';
@@ -1013,18 +1012,6 @@ export function reportProgress(message: string, progress?: ProgressHandle) {
     }
 }
 
-/**
- * Sets up a chokidar watcher to listen for any file changes (add, change, unlink).
- * @param watcher The chokidar FSWatcher instance.
- * @param listener The listener function to call on file changes.
- * @returns The chokidar FSWatcher instance with the listener attached.
- */
-export function chokidarOnAnyChange(watcher: chokidar.FSWatcher, listener: (path: string, stats?: fs.Stats | undefined) => void) {
-    return watcher.on('add', listener)
-        .on('change', listener)
-        .on('unlink', listener);
-}
-
 /**
  * Checks if the given value is a string.
  * @param x The value to check.