fix(react): stale lesson data after navigation

e2e/src/content/tutorial/tests/navigation/layout-change-from/content.md

@@ -0,0 +1,13 @@
+---
+type: lesson
+title: Layout change from
+template: default
+mainCommand: node index.mjs
+previews:
+  - title: "Custom preview"
+    port: 8000
+---
+
+# Navigation test - Layout change from
+
+This page should show previw

e2e/src/content/tutorial/tests/navigation/layout-change-to/content.md

@@ -0,0 +1,12 @@
+---
+type: lesson
+title: Layout change to
+previews: false
+terminal:
+  panels:
+    - ["terminal", "Custom Terminal"]
+---
+
+# Navigation test - Layout change to
+
+This page should not show previw. It should show terminal instead.

e2e/src/content/tutorial/tests/navigation/meta.md

@@ -5,6 +5,8 @@ lessons:
   - page-one
   - page-two
   - page-three
+  - layout-change-from
+  - layout-change-to
 mainCommand: ''
 prepareCommands: []
 ---

e2e/test/navigation.test.ts

@@ -1,9 +1,9 @@
 import { test, expect } from '@playwright/test';
 
-const BASE_URL = '/tests/navigation/page-one';
+const BASE_URL = '/tests/navigation';
 
 test('user can navigate between lessons using nav bar links', async ({ page }) => {
-  await page.goto(BASE_URL);
+  await page.goto(`${BASE_URL}/page-one`);
   await expect(page.getByRole('heading', { level: 1, name: 'Navigation test - Page one' })).toBeVisible();
 
   // navigate forwards
@@ -21,10 +21,32 @@ test('user can navigate between lessons using nav bar links', async ({ page }) =
 });
 
 test('user can navigate between lessons using breadcrumbs', async ({ page }) => {
-  await page.goto(BASE_URL);
+  await page.goto(`${BASE_URL}/page-one`);
 
   await page.getByRole('button', { name: 'Tests / Navigation / Page one' }).click({ force: true });
   await page.getByRole('region', { name: 'Navigation' }).getByRole('link', { name: 'Page three' }).click();
 
   await expect(page.getByRole('heading', { level: 1, name: 'Navigation test - Page three' })).toBeVisible();
 });
+
+test("user should see metadata's layout changes after navigation (#318)", async ({ page }) => {
+  await page.goto(`${BASE_URL}/layout-change-from`);
+
+  // first page should have preview visible
+  await expect(page.getByRole('heading', { level: 1, name: 'Navigation test - Layout change from' })).toBeVisible();
+  await expect(page.getByText('Custom preview')).toBeVisible();
+
+  await page.getByRole('link', { name: 'Layout change to' }).click();
+  await expect(page.getByRole('heading', { level: 1, name: 'Navigation test - Layout change to' })).toBeVisible();
+
+  // second page should have preview hidden, terminal visible
+
+  /* eslint-disable multiline-comment-style */
+  // TODO: Requires #245
+  // await expect(page.getByText('Preparing Environment')).not.toBeVisible();
+
+  await expect(page.getByRole('tab', { name: 'Custom Terminal', selected: true })).toBeVisible();
+  await expect(page.getByRole('tabpanel', { name: 'Custom Terminal' })).toContainText('~/tutorial', {
+    useInnerText: true,
+  });
+});

packages/react/src/Panels/WorkspacePanel.tsx

@@ -32,6 +32,13 @@ interface TerminalProps extends PanelProps {
  * This component is the orchestrator between various interactive components.
  */
 export function WorkspacePanel({ tutorialStore, theme }: Props) {
+  /**
+   * Re-render when lesson changes.
+   * The `tutorialStore.hasEditor()` and other methods below access
+   * stale data as they are not reactive.
+   */
+  useStore(tutorialStore.ref);
+
   const hasEditor = tutorialStore.hasEditor();
   const hasPreviews = tutorialStore.hasPreviews();
   const hideTerminalPanel = !tutorialStore.hasTerminalPanel();
@@ -89,6 +96,7 @@ function EditorSection({ theme, tutorialStore, hasEditor }: PanelProps) {
   const selectedFile = useStore(tutorialStore.selectedFile);
   const currentDocument = useStore(tutorialStore.currentDocument);
   const lessonFullyLoaded = useStore(tutorialStore.lessonFullyLoaded);
+  const storeRef = useStore(tutorialStore.ref);
 
   const lesson = tutorialStore.lesson!;
 
@@ -116,7 +124,7 @@ function EditorSection({ theme, tutorialStore, hasEditor }: PanelProps) {
     } else {
       setHelpAction('reset');
     }
-  }, [tutorialStore.ref]);
+  }, [storeRef]);
 
   return (
     <Panel
@@ -128,7 +136,7 @@ function EditorSection({ theme, tutorialStore, hasEditor }: PanelProps) {
       className="transition-theme bg-tk-elements-panel-backgroundColor text-tk-elements-panel-textColor"
     >
       <EditorPanel
-        id={tutorialStore.ref}
+        id={storeRef}
         theme={theme}
         showFileTree={tutorialStore.hasFileTree()}
         editorDocument={currentDocument}
@@ -157,6 +165,7 @@ function PreviewsSection({
   const previewRef = useRef<ImperativePreviewHandle>(null);
   const lesson = tutorialStore.lesson!;
   const terminalConfig = useStore(tutorialStore.terminalConfig);
+  const storeRef = useStore(tutorialStore.ref);
 
   function showTerminal() {
     const { current: terminal } = terminalPanelRef;
@@ -206,7 +215,7 @@ function PreviewsSection({
     });
 
     return () => unsubscribe();
-  }, [tutorialStore.ref]);
+  }, [storeRef]);
 
   return (
     <Panel

packages/runtime/src/store/index.ts

@@ -39,7 +39,7 @@ export class TutorialStore {
   private _lessonFilesFetcher: LessonFilesFetcher;
   private _lessonTask: Task<unknown> | undefined;
   private _lesson: Lesson | undefined;
-  private _ref: number = 1;
+  private _ref = atom(1);
   private _themeRef = atom(1);
 
   private _lessonFiles: Files | undefined;
@@ -135,7 +135,7 @@ export class TutorialStore {
 
     this._lessonTask?.cancel();
 
-    this._ref += 1;
+    this._ref.set(1 + (this._ref.value || 0));
     this._lesson = lesson;
     this.lessonFullyLoaded.set(false);
 
@@ -219,7 +219,7 @@ export class TutorialStore {
     return this._lesson;
   }
 
-  get ref(): unknown {
+  get ref(): ReadableAtom<unknown> {
     return this._ref;
   }