[History]: Fix redo after update/publish with transient edits

packages/core-data/src/reducer.js

@@ -431,7 +431,16 @@ export function undo( state = UNDO_INITIAL_STATE, action ) {
 					// to continue as if we were creating an explicit undo level. This
 					// will result in an extra undo level being appended with the flattened
 					// undo values.
+					// We also have to take into account if the `lastEditAction` had opted out
+					// of being tracked in undo history, like the action that persists the latest
+					// content right before saving. In that case we have to update the `lastEditAction`
+					// to avoid returning early before applying the existing flattened undos.
 					isCreateUndoLevel = true;
+					if ( ! lastEditAction.meta.undo ) {
+						lastEditAction.meta.undo = {
+							edits: {},
+						};
+					}
 					action = lastEditAction;
 				} else {
 					return nextState;

packages/e2e-tests/specs/editor/various/undo.test.js

@@ -420,4 +420,25 @@ describe( 'undo', () => {
 		// Expect "1".
 		expect( await getEditedPostContent() ).toMatchSnapshot();
 	} );
+
+	it( 'should be able to undo and redo when transient changes have been made and we update/publish', async () => {
+		// Typing consecutive characters in a `Paragraph` block updates the same
+		// block attribute as in the previous action and results in transient edits
+		// and skipping `undo` history steps.
+		const text = 'tonis';
+		await clickBlockAppender();
+		await page.keyboard.type( text );
+		await publishPost();
+		await pressKeyWithModifier( 'primary', 'z' );
+		expect( await getEditedPostContent() ).toBe( '' );
+		await page.waitForSelector(
+			'.editor-history__redo[aria-disabled="false"]'
+		);
+		await page.click( '.editor-history__redo[aria-disabled="false"]' );
+		expect( await getEditedPostContent() ).toMatchInlineSnapshot( `
+		"<!-- wp:paragraph -->
+		<p>tonis</p>
+		<!-- /wp:paragraph -->"
+	` );
+	} );
 } );

packages/e2e-tests/specs/site-editor/template-revert.test.js

@@ -22,29 +22,31 @@ const {
 	disableWelcomeGuide,
 } = siteEditor;
 
-const assertSaveButtonIsDisabled = () =>
+const assertSaveButtonIsDisabled = async () =>
 	page.waitForSelector(
 		'.edit-site-save-button__button[aria-disabled="true"]'
 	);
 
-const assertSaveButtonIsEnabled = () =>
+const assertSaveButtonIsEnabled = async () =>
 	page.waitForSelector(
 		'.edit-site-save-button__button[aria-disabled="false"]'
 	);
 
-const waitForNotice = () => page.waitForSelector( '.components-snackbar' );
-
 const clickButtonInNotice = async () => {
 	const selector = '.components-snackbar button';
 	await page.waitForSelector( selector );
 	await page.click( selector );
 };
 
-const clickUndoInHeaderToolbar = () =>
+const clickUndoInHeaderToolbar = async () =>
 	page.click( '.edit-site-header__toolbar button[aria-label="Undo"]' );
 
-const clickRedoInHeaderToolbar = () =>
-	page.click( '.edit-site-header__toolbar button[aria-label="Redo"]' );
+const clickRedoInHeaderToolbar = async () => {
+	await page.waitForSelector(
+		'.edit-site-header__toolbar button[aria-label="Redo"][aria-disabled="false"]'
+	);
+	return page.click( '.edit-site-header__toolbar button[aria-label="Redo"]' );
+};
 
 const undoRevertInHeaderToolbar = async () => {
 	await clickUndoInHeaderToolbar();
@@ -72,7 +74,9 @@ const save = async () => {
 const revertTemplate = async () => {
 	await page.click( '.edit-site-document-actions__get-info' );
 	await page.click( '.edit-site-template-details__revert-button' );
-	await waitForNotice();
+	await page.waitForXPath(
+		'//*[contains(@class, "components-snackbar") and contains(text(), "Template reverted")]'
+	);
 	await assertSaveButtonIsEnabled();
 };
 
@@ -164,15 +168,14 @@ describe( 'Template Revert', () => {
 		expect( contentBefore ).toBe( contentAfter );
 	} );
 
-	it.skip( 'should show the original content after revert, clicking undo then redo in the header toolbar', async () => {
+	it( 'should show the original content after revert, clicking undo then redo in the header toolbar', async () => {
 		const contentBefore = await getEditedPostContent();
 
 		await addDummyText();
 		await save();
 		await revertTemplate();
 		await save();
 		await undoRevertInHeaderToolbar();
-		// there's a bug which probably also exists where the redo button stays disabled.
 		await clickRedoInHeaderToolbar();
 
 		const contentAfter = await getEditedPostContent();

test/emptytheme/block-templates/index.html

@@ -1,9 +1,10 @@
 <!-- wp:template-part {"slug":"header","tagName":"header"} /-->
 
 <!-- wp:query {"queryId":1,"query":{"offset":0,"postType":"post","categoryIds":[],"tagIds":[],"order":"desc","orderBy":"date","author":"","search":"","sticky":""}} -->
-<!-- wp:post-template -->
-<!-- wp:post-title {"isLink":true} /-->
-
-<!-- wp:post-excerpt /-->
-<!-- /wp:post-template -->
-<!-- /wp:query -->
+<div class="wp-block-query">
+	<!-- wp:post-template -->
+	<!-- wp:post-title {"isLink":true} /-->
+	<!-- wp:post-excerpt /-->
+	<!-- /wp:post-template -->
+</div>
+<!-- /wp:query -->