Enter editing mode via Enter or Spacebar (#58795)

There was a regression in being able to enter editing mode via keydown on the site editor due to the onKeydown event being blocked. This allows an onKeydown prop to be fired if passed to the iframe.

Also added a test to check for this as well as general keyboard navigation of the site editor in view mode.

---------
Co-authored-by: jeryj <jeryj@git.wordpress.org>
Co-authored-by: scruffian <scruffian@git.wordpress.org>
Co-authored-by: draganescu <andraganescu@git.wordpress.org>
Co-authored-by: t-hamano <wildworks@git.wordpress.org>
Co-authored-by: alexstine <alexstine@git.wordpress.org>

packages/block-editor/src/components/iframe/index.js

@@ -273,13 +273,16 @@ function Iframe( {
 				src={ src }
 				title={ __( 'Editor canvas' ) }
 				onKeyDown={ ( event ) => {
+					if ( props.onKeyDown ) {
+						props.onKeyDown( event );
+					}
 					// If the event originates from inside the iframe, it means
 					// it bubbled through the portal, but only with React
 					// events. We need to to bubble native events as well,
 					// though by doing so we also trigger another React event,
 					// so we need to stop the propagation of this event to avoid
 					// duplication.
-					if (
+					else if (
 						event.currentTarget.ownerDocument !==
 						event.target.ownerDocument
 					) {

test/e2e/specs/site-editor/navigation.spec.js

@@ -0,0 +1,119 @@
+/**
+ * WordPress dependencies
+ */
+const { test, expect } = require( '@wordpress/e2e-test-utils-playwright' );
+
+test.use( {
+	editorNavigationUtils: async ( { page, pageUtils }, use ) => {
+		await use( new EditorNavigationUtils( { page, pageUtils } ) );
+	},
+} );
+
+test.describe( 'Site editor navigation', () => {
+	test.beforeAll( async ( { requestUtils } ) => {
+		await requestUtils.activateTheme( 'emptytheme' );
+	} );
+
+	test.afterAll( async ( { requestUtils } ) => {
+		await requestUtils.activateTheme( 'twentytwentyone' );
+	} );
+
+	test( 'Can use keyboard to navigate the site editor', async ( {
+		admin,
+		editorNavigationUtils,
+		page,
+		pageUtils,
+	} ) => {
+		await admin.visitSiteEditor();
+
+		// Test: Can navigate to a sidebar item and into its subnavigation frame without losing focus
+		// Go to the Pages button
+
+		await editorNavigationUtils.tabToLabel( 'Pages' );
+
+		await expect(
+			page.getByRole( 'button', { name: 'Pages' } )
+		).toBeFocused();
+		await pageUtils.pressKeys( 'Enter' );
+		// We should be in the Pages sidebar
+		await expect(
+			page.getByRole( 'button', { name: 'Back', exact: true } )
+		).toBeFocused();
+		await pageUtils.pressKeys( 'Enter' );
+		// Go back to the main navigation
+		await expect(
+			page.getByRole( 'button', { name: 'Pages' } )
+		).toBeFocused();
+
+		// Test: Can navigate into the iframe using the keyboard
+		await editorNavigationUtils.tabToLabel( 'Editor Canvas' );
+		const editorCanvasButton = page.getByRole( 'button', {
+			name: 'Editor Canvas',
+		} );
+		await expect( editorCanvasButton ).toBeFocused();
+		// Enter into the site editor frame
+		await pageUtils.pressKeys( 'Enter' );
+		// Focus should be on the iframe without the button role
+		await expect(
+			page.locator( 'iframe[name="editor-canvas"]' )
+		).toBeFocused();
+		// The button role should have been removed from the iframe.
+		await expect( editorCanvasButton ).toBeHidden();
+
+		// Test to make sure a Tab keypress works as expected.
+		// As of this writing, we are in select mode and a tab
+		// keypress will reveal the header template select mode
+		// button. This test is not documenting that we _want_
+		// that action, but checking that we are within the site
+		// editor and keypresses work as intened.
+		await pageUtils.pressKeys( 'Tab' );
+		await expect(
+			page.getByRole( 'button', {
+				name: 'Template Part Block. Row 1. header',
+			} )
+		).toBeFocused();
+
+		// Test: We can go back to the main navigation from the editor frame
+		// Move to the document toolbar
+		await pageUtils.pressKeys( 'alt+F10' );
+		// Go to the open navigation button
+		await pageUtils.pressKeys( 'shift+Tab' );
+
+		// Open the sidebar again
+		await expect(
+			page.getByRole( 'button', {
+				name: 'Open Navigation',
+				exact: true,
+			} )
+		).toBeFocused();
+		await pageUtils.pressKeys( 'Enter' );
+
+		await expect(
+			page.getByLabel( 'Go to the Dashboard' ).first()
+		).toBeFocused();
+		// We should have our editor canvas button back
+		await expect( editorCanvasButton ).toBeVisible();
+	} );
+} );
+
+class EditorNavigationUtils {
+	constructor( { page, pageUtils } ) {
+		this.page = page;
+		this.pageUtils = pageUtils;
+	}
+
+	async tabToLabel( label, times = 10 ) {
+		for ( let i = 0; i < times; i++ ) {
+			await this.pageUtils.pressKeys( 'Tab' );
+			const activeLabel = await this.page.evaluate( () => {
+				return (
+					document.activeElement.getAttribute( 'aria-label' ) ||
+					document.activeElement.textContent
+				);
+			} );
+			if ( activeLabel === label ) {
+				return;
+			}
+		}
+	}
+}