Prepopulate the Find in Page search text with the currently selected text in the page (microsoft#291800)

* Prepopulate Find textbox

* Add warning taken from preload.ts

* Small changes

* Refactor preload script comments for clarity and security emphasis

* Small comment change

* Small comment change

* Update comment

* Use isolated world instead of main world

* Comment update

* Update comment

* Update comment

* PR Feedback

* Small comment

Author: jruales

build/checker/layersChecker.ts

@@ -61,6 +61,12 @@ const RULES: IRule[] = [
 		disallowedTypes: NATIVE_TYPES,
 	},
 
+	// Browser view preload script
+	{
+		target: '**/vs/platform/browserView/electron-browser/preload-browserView.ts',
+		disallowedTypes: NATIVE_TYPES,
+	},
+
 	// Common
 	{
 		target: '**/vs/**/common/**',

build/checker/tsconfig.electron-browser.json

@@ -16,6 +16,7 @@
 		"../../src/**/test/**",
 		"../../src/**/fixtures/**",
 		"../../src/vs/base/parts/sandbox/electron-browser/preload.ts", 		// Preload scripts for Electron sandbox
-		"../../src/vs/base/parts/sandbox/electron-browser/preload-aux.ts"	// have limited access to node.js APIs
+		"../../src/vs/base/parts/sandbox/electron-browser/preload-aux.ts",	// have limited access to node.js APIs
+		"../../src/vs/platform/browserView/electron-browser/preload-browserView.ts"	// Browser view preload script
 	]
 }

build/gulpfile.vscode.ts

@@ -68,6 +68,7 @@ const vscodeResourceIncludes = [
 	// Electron Preload
 	'out-build/vs/base/parts/sandbox/electron-browser/preload.js',
 	'out-build/vs/base/parts/sandbox/electron-browser/preload-aux.js',
+	'out-build/vs/platform/browserView/electron-browser/preload-browserView.js',
 
 	// Node Scripts
 	'out-build/vs/base/node/{terminateProcess.sh,cpuUsage.sh,ps.sh}',

src/vs/platform/browserView/common/browserView.ts

@@ -117,6 +117,11 @@ export enum BrowserViewStorageScope {
 
 export const ipcBrowserViewChannelName = 'browserView';
 
+/**
+ * This should match the isolated world ID defined in `preload-browserView.ts`.
+ */
+export const browserViewIsolatedWorldId = 999;
+
 export interface IBrowserViewService {
 	/**
 	 * Dynamic events that return an Event for a specific browser view ID.
@@ -246,6 +251,14 @@ export interface IBrowserViewService {
 	 */
 	stopFindInPage(id: string, keepSelection?: boolean): Promise<void>;
 
+	/**
+	 * Get the currently selected text in the browser view.
+	 * Returns immediately with empty string if the page is still loading.
+	 * @param id The browser view identifier
+	 * @returns The selected text, or empty string if no selection or page is loading
+	 */
+	getSelectedText(id: string): Promise<string>;
+
 	/**
 	 * Clear all storage data for the global browser session
 	 */

src/vs/platform/browserView/electron-browser/preload-browserView.ts

@@ -0,0 +1,53 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+/* eslint-disable no-restricted-globals */
+
+/**
+ * Preload script for pages loaded in Integrated Browser
+ *
+ * It runs in an isolated context that Electron calls an "isolated world".
+ * Specifically the isolated world with worldId 999, which shows in DevTools as "Electron Isolated Context".
+ * Despite being isolated, it still runs on the same page as the JS from the actual loaded website
+ * which runs on the so-called "main world" (worldId 0. In DevTools as "top").
+ *
+ * Learn more: see Electron docs for Security, contextBridge, and Context Isolation.
+ */
+(function () {
+
+	const { contextBridge } = require('electron');
+
+	// #######################################################################
+	// ###                                                                 ###
+	// ###       !!! DO NOT USE GET/SET PROPERTIES ANYWHERE HERE !!!       ###
+	// ###       !!!  UNLESS THE ACCESS IS WITHOUT SIDE EFFECTS  !!!       ###
+	// ###       (https://github.com/electron/electron/issues/25516)       ###
+	// ###                                                                 ###
+	// #######################################################################
+	const globals = {
+		/**
+		 * Get the currently selected text in the page.
+		 */
+		getSelectedText(): string {
+			try {
+				// Even if the page has overridden window.getSelection, our call here will still reach the original
+				// implementation. That's because Electron proxies functions, such as getSelectedText here, that are
+				// exposed to a different context via exposeInIsolatedWorld or exposeInMainWorld.
+				return window.getSelection()?.toString() ?? '';
+			} catch {
+				return '';
+			}
+		}
+	};
+
+	try {
+		// Use `contextBridge` APIs to expose globals to the same isolated world where this preload script runs (worldId 999).
+		// The globals object will be recursively frozen (and for functions also proxied) by Electron to prevent
+		// modification within the given context.
+		contextBridge.exposeInIsolatedWorld(999, 'browserViewAPI', globals);
+	} catch (error) {
+		console.error(error);
+	}
+}());

src/vs/platform/browserView/electron-main/browserView.ts

@@ -4,10 +4,11 @@
  *--------------------------------------------------------------------------------------------*/
 
 import { WebContentsView, webContents } from 'electron';
+import { FileAccess } from '../../../base/common/network.js';
 import { Disposable } from '../../../base/common/lifecycle.js';
 import { Emitter, Event } from '../../../base/common/event.js';
 import { VSBuffer } from '../../../base/common/buffer.js';
-import { IBrowserViewBounds, IBrowserViewDevToolsStateEvent, IBrowserViewFocusEvent, IBrowserViewKeyDownEvent, IBrowserViewState, IBrowserViewNavigationEvent, IBrowserViewLoadingEvent, IBrowserViewLoadError, IBrowserViewTitleChangeEvent, IBrowserViewFaviconChangeEvent, IBrowserViewNewPageRequest, BrowserViewStorageScope, IBrowserViewCaptureScreenshotOptions, IBrowserViewFindInPageOptions, IBrowserViewFindInPageResult, IBrowserViewVisibilityEvent, BrowserNewPageLocation } from '../common/browserView.js';
+import { IBrowserViewBounds, IBrowserViewDevToolsStateEvent, IBrowserViewFocusEvent, IBrowserViewKeyDownEvent, IBrowserViewState, IBrowserViewNavigationEvent, IBrowserViewLoadingEvent, IBrowserViewLoadError, IBrowserViewTitleChangeEvent, IBrowserViewFaviconChangeEvent, IBrowserViewNewPageRequest, BrowserViewStorageScope, IBrowserViewCaptureScreenshotOptions, IBrowserViewFindInPageOptions, IBrowserViewFindInPageResult, IBrowserViewVisibilityEvent, BrowserNewPageLocation, browserViewIsolatedWorldId } from '../common/browserView.js';
 import { EVENT_KEY_CODE_MAP, KeyCode, KeyMod, SCAN_CODE_STR_TO_EVENT_KEY_CODE } from '../../../base/common/keyCodes.js';
 import { IWindowsMainService } from '../../windows/electron-main/windows.js';
 import { IBaseWindow, ICodeWindow } from '../../window/electron-main/window.js';
@@ -96,6 +97,7 @@ export class BrowserView extends Disposable {
 			sandbox: true,
 			webviewTag: false,
 			session: viewSession,
+			preload: FileAccess.asFileUri('vs/platform/browserView/electron-browser/preload-browserView.js').fsPath,
 
 			// TODO@kycutler: Remove this once https://github.com/electron/electron/issues/42578 is fixed
 			type: 'browserView'
@@ -535,6 +537,23 @@ export class BrowserView extends Disposable {
 		this._view.webContents.stopFindInPage(keepSelection ? 'keepSelection' : 'clearSelection');
 	}
 
+	/**
+	 * Get the currently selected text in the browser view.
+	 * Returns immediately with empty string if the page is still loading.
+	 */
+	async getSelectedText(): Promise<string> {
+		// we don't want to wait for the page to finish loading, which executeJavaScript normally does.
+		if (this._view.webContents.isLoading()) {
+			return '';
+		}
+		try {
+			// Uses our preloaded contextBridge-exposed API.
+			return await this._view.webContents.executeJavaScriptInIsolatedWorld(browserViewIsolatedWorldId, [{ code: 'window.browserViewAPI?.getSelectedText?.() ?? ""' }]);
+		} catch {
+			return '';
+		}
+	}
+
 	/**
 	 * Clear all storage data for this browser view's session
 	 */

src/vs/platform/browserView/electron-main/browserViewMainService.ts

@@ -243,6 +243,10 @@ export class BrowserViewMainService extends Disposable implements IBrowserViewMa
 		return this._getBrowserView(id).stopFindInPage(keepSelection);
 	}
 
+	async getSelectedText(id: string): Promise<string> {
+		return this._getBrowserView(id).getSelectedText();
+	}
+
 	async clearStorage(id: string): Promise<void> {
 		return this._getBrowserView(id).clearStorage();
 	}

src/vs/workbench/contrib/browserView/common/browserView.ts

@@ -118,6 +118,7 @@ export interface IBrowserViewModel extends IDisposable {
 	focus(): Promise<void>;
 	findInPage(text: string, options?: IBrowserViewFindInPageOptions): Promise<void>;
 	stopFindInPage(keepSelection?: boolean): Promise<void>;
+	getSelectedText(): Promise<string>;
 	clearStorage(): Promise<void>;
 }
 
@@ -336,6 +337,10 @@ export class BrowserViewModel extends Disposable implements IBrowserViewModel {
 		return this.browserViewService.stopFindInPage(this.id, keepSelection);
 	}
 
+	async getSelectedText(): Promise<string> {
+		return this.browserViewService.getSelectedText(this.id);
+	}
+
 	async clearStorage(): Promise<void> {
 		return this.browserViewService.clearStorage(this.id);
 	}

src/vs/workbench/contrib/browserView/electron-browser/browserEditor.ts

@@ -600,10 +600,15 @@ export class BrowserEditor extends EditorPane {
 	}
 
 	/**
-	 * Show the find widget
+	 * Show the find widget, optionally pre-populated with selected text from the browser view
 	 */
-	showFind(): void {
-		this._findWidget.value.reveal();
+	async showFind(): Promise<void> {
+		// Get selected text from the browser view to pre-populate the search box.
+		const selectedText = await this._model?.getSelectedText();
+
+		// Only use the selected text if it doesn't contain newlines (single line selection)
+		const textToReveal = selectedText && !/[\r\n]/.test(selectedText) ? selectedText : undefined;
+		this._findWidget.value.reveal(textToReveal);
 		this._findWidget.value.layout(this._findWidgetContainer.clientWidth);
 	}