Testing: Reimplement pressKeyWithModifier to emulate Cmd+A in macOS

packages/e2e-test-utils/src/login-user.js

@@ -1,4 +1,3 @@
-
 /**
  * Internal dependencies
  */

packages/e2e-test-utils/src/press-key-with-modifier.js

@@ -8,6 +8,78 @@ import { capitalize } from 'lodash';
  */
 import { modifiers, SHIFT, ALT, CTRL } from '@wordpress/keycodes';
 
+/**
+ * Emulates a Ctrl+A SelectAll key combination by dispatching custom keyboard
+ * events and using the results of those events to determine whether to call
+ * `document.execCommand( 'selectall' );`. This is necessary because Puppeteer
+ * does not emulate Ctrl+A SelectAll in macOS. Events are dispatched to ensure
+ * that any `Event#preventDefault` which would have normally occurred in the
+ * application as a result of Ctrl+A is respected.
+ *
+ * @link https://github.com/GoogleChrome/puppeteer/issues/1313
+ * @link https://w3c.github.io/uievents/tools/key-event-viewer.html
+ *
+ * @return {Promise} Promise resolving once the SelectAll emulation completes.
+ */
+async function emulateSelectAll() {
+	await page.evaluate( () => {
+		const isMac = /Mac|iPod|iPhone|iPad/.test( window.navigator.platform );
+
+		document.activeElement.dispatchEvent(
+			new KeyboardEvent( 'keydown', {
+				bubbles: true,
+				cancelable: true,
+				key: isMac ? 'Meta' : 'Control',
+				code: isMac ? 'MetaLeft' : 'ControlLeft',
+				location: window.KeyboardEvent.DOM_KEY_LOCATION_LEFT,
+				getModifierState: ( keyArg ) => keyArg === ( isMac ? 'Meta' : 'Control' ),
+				ctrlKey: ! isMac,
+				metaKey: isMac,
+				charCode: 0,
+				keyCode: isMac ? 93 : 17,
+				which: isMac ? 93 : 17,
+			} )
+		);
+
+		const preventableEvent = new KeyboardEvent( 'keydown', {
+			bubbles: true,
+			cancelable: true,
+			key: 'a',
+			code: 'KeyA',
+			location: window.KeyboardEvent.DOM_KEY_LOCATION_STANDARD,
+			getModifierState: ( keyArg ) => keyArg === ( isMac ? 'Meta' : 'Control' ),
+			ctrlKey: ! isMac,
+			metaKey: isMac,
+			charCode: 0,
+			keyCode: 65,
+			which: 65,
+		} );
+
+		const wasPrevented = (
+			! document.activeElement.dispatchEvent( preventableEvent ) ||
+			preventableEvent.defaultPrevented
+		);
+
+		if ( ! wasPrevented ) {
+			document.execCommand( 'selectall', false, null );
+		}
+
+		document.activeElement.dispatchEvent(
+			new KeyboardEvent( 'keyup', {
+				bubbles: true,
+				cancelable: true,
+				key: isMac ? 'Meta' : 'Control',
+				code: isMac ? 'MetaLeft' : 'ControlLeft',
+				location: window.KeyboardEvent.DOM_KEY_LOCATION_LEFT,
+				getModifierState: () => false,
+				charCode: 0,
+				keyCode: isMac ? 93 : 17,
+				which: isMac ? 93 : 17,
+			} ),
+		);
+	} );
+}
+
 /**
  * Performs a key press with modifier (Shift, Control, Meta, Alt), where each modifier
  * is normalized to platform-specific modifier.
@@ -16,6 +88,10 @@ import { modifiers, SHIFT, ALT, CTRL } from '@wordpress/keycodes';
  * @param {string} key Key to press while modifier held.
  */
 export async function pressKeyWithModifier( modifier, key ) {
+	if ( modifier.toLowerCase() === 'primary' && key.toLowerCase() === 'a' ) {
+		return await emulateSelectAll();
+	}
+
 	const isAppleOS = () => process.platform === 'darwin';
 	const overWrittenModifiers = {
 		...modifiers,

packages/e2e-tests/specs/block-hierarchy-navigation.test.js

@@ -98,11 +98,8 @@ describe( 'Navigating the block hierarchy', () => {
 		await openBlockNavigator();
 		await page.keyboard.press( 'Space' );
 
-		// Replace its content
-		// note Cmd/Ctrl + A doesn't work on Mac with Pupetter right now
-		// https://github.com/GoogleChrome/puppeteer/issues/1313
-		await pressKeyTimes( 'ArrowRight', textString.length );
-		await pressKeyTimes( 'Backspace', textString.length );
+		// Replace its content.
+		await pressKeyWithModifier( 'primary', 'a' );
 		await page.keyboard.type( 'and I say hello' );
 
 		expect( await getEditedPostContent() ).toMatchSnapshot();