fix(astro): sorting of mixed hierarchy parts

Author: AriPerkkio

e2e/src-custom/lessons-in-part/content/tutorial/part-one/lesson-one/content.md renamed to e2e/src-custom/lessons-in-part/content/tutorial/part-one/lesson-1/content.md

@@ -0,0 +1,8 @@
+---
+type: lesson
+title: Lesson three
+---
+
+# Lessons in part test - Lesson three
+
+Lesson in chapter

e2e/src-custom/lessons-in-part/content/tutorial/part-one/lesson-two/content.md renamed to e2e/src-custom/lessons-in-part/content/tutorial/part-one/lesson-2/content.md

@@ -0,0 +1,8 @@
+---
+type: lesson
+title: Lesson four
+---
+
+# Lessons in part test - Lesson four
+
+Lesson in chapter

e2e/src-custom/lessons-in-part/content/tutorial/part-two/chapter-one/lesson-3/content.md

@@ -0,0 +1,4 @@
+---
+type: chapter
+title: 'Chapter one'
+---

e2e/src-custom/lessons-in-part/content/tutorial/part-two/chapter-one/lesson-4/content.md

@@ -0,0 +1,4 @@
+---
+type: part
+title: 'Part two'
+---

e2e/src-custom/lessons-in-part/content/tutorial/part-two/chapter-one/meta.md

@@ -1,7 +1,7 @@
 import { test, expect } from '@playwright/test';
 
 test('user can navigate between lessons using breadcrumbs', async ({ page }) => {
-  await page.goto('/part-one/lesson-one');
+  await page.goto('/');
 
   await expect(page.getByRole('heading', { level: 1, name: 'Lessons in part test - Lesson one' })).toBeVisible();
   await expect(page.getByText('Lesson in part without chapter')).toBeVisible();
@@ -13,7 +13,50 @@ test('user can navigate between lessons using breadcrumbs', async ({ page }) =>
     await expect(page.locator('[data-state="open"]', { has: button })).toBeVisible({ timeout: 50 });
   }).toPass();
 
-  await page.getByRole('navigation').getByRole('link', { name: 'Lesson two' }).click();
+  const navigation = page.getByRole('navigation');
+  await navigation.getByRole('region', { name: 'Part 1: Part one' }).getByRole('link', { name: 'Lesson two' }).click();
 
   await expect(page.getByRole('heading', { level: 1, name: 'Lessons in part test - Lesson two' })).toBeVisible();
+  await expect(page.getByText('Lesson in part without chapter')).toBeVisible();
+
+  await expect(async () => {
+    const button = page.getByRole('button', { name: 'Part one / Lesson two' });
+    await button.click();
+    await expect(page.locator('[data-state="open"]', { has: button })).toBeVisible({ timeout: 50 });
+  }).toPass();
+
+  // expand part
+  await navigation.getByRole('button', { name: 'Part 2: Part two' }).click();
+
+  // expand chapter
+  await navigation
+    .getByRole('region', { name: 'Part 2: Part two' })
+    .getByRole('button', { name: 'Chapter one' })
+    .click();
+
+  // select lesson
+  await navigation.getByRole('region', { name: 'Chapter one' }).getByRole('link', { name: 'Lesson three' }).click();
+
+  await expect(page.getByRole('heading', { level: 1, name: 'Lessons in part test - Lesson three' })).toBeVisible();
+  await expect(page.getByText('Lesson in chapter')).toBeVisible();
+});
+
+test('user can navigate between lessons using nav bar links', async ({ page }) => {
+  await page.goto('/');
+  await expect(page.getByRole('heading', { level: 1, name: 'Lessons in part test - Lesson one' })).toBeVisible();
+  await expect(page.getByText('Lesson in part without chapter')).toBeVisible();
+
+  await navigateToPage('Lesson two');
+  await expect(page.getByText('Lesson in part without chapter')).toBeVisible();
+
+  await navigateToPage('Lesson three');
+  await expect(page.getByText('Lesson in chapter')).toBeVisible();
+
+  await navigateToPage('Lesson four');
+  await expect(page.getByText('Lesson in chapter')).toBeVisible();
+
+  async function navigateToPage(title: string) {
+    await page.getByRole('link', { name: title }).click();
+    await expect(page.getByRole('heading', { level: 1, name: `Lessons in part test - ${title}` })).toBeVisible();
+  }
 });

e2e/src-custom/lessons-in-part/content/tutorial/part-two/meta.md

@@ -136,6 +136,41 @@ test('lessons with identical names in different chapters', async () => {
   expect(lessons[1].part?.id).toBe('1-part');
 });
 
+test('lessons with identical names in mixed hierarchy', async () => {
+  getCollection.mockReturnValueOnce([
+    { id: 'meta.md', ...tutorial },
+    { id: '1-part/meta.md', ...part },
+    { id: '2-part/meta.md', ...part },
+    { id: '2-part/2-chapter/meta.md', ...chapter },
+
+    { id: '1-part/identical-lesson-name/content.md', ...lesson },
+    { id: '1-part/2nd-identical-lesson-name/content.md', ...lesson },
+
+    { id: '2-part/2-chapter/identical-lesson-name/content.md', ...lesson },
+    { id: '2-part/2-chapter/2nd-identical-lesson-name/content.md', ...lesson },
+  ]);
+
+  const collection = await getTutorial();
+  const lessons = collection.lessons;
+
+  // verify that lesson.id is not used to define what makes a lesson unique (part.id + chapter.id too)
+  expect(lessons).toHaveLength(4);
+  expect(lessons[0].id).toBe('identical-lesson-name');
+  expect(lessons[1].id).toBe('2nd-identical-lesson-name');
+  expect(lessons[2].id).toBe('identical-lesson-name');
+  expect(lessons[3].id).toBe('2nd-identical-lesson-name');
+
+  expect(lessons[0].chapter?.id).toBe(undefined);
+  expect(lessons[1].chapter?.id).toBe(undefined);
+  expect(lessons[2].chapter?.id).toBe('2-chapter');
+  expect(lessons[3].chapter?.id).toBe('2-chapter');
+
+  expect(lessons[0].part?.id).toBe('1-part');
+  expect(lessons[1].part?.id).toBe('1-part');
+  expect(lessons[2].part?.id).toBe('2-part');
+  expect(lessons[3].part?.id).toBe('2-part');
+});
+
 test('single part and lesson, no chapter', async (ctx) => {
   getCollection.mockReturnValueOnce([
     { id: 'meta.md', ...tutorial },

e2e/test/navigation.lessons-in-part.test.ts

@@ -366,14 +366,16 @@ function assertTutorialStructure(tutorial: Tutorial) {
 }
 
 function sortTutorialLessons(tutorial: Tutorial, metadata: TutorialSchema) {
-  const lessonOrder: Lesson['id'][] = [];
   const lessonIds = tutorial.lessons.map((lesson) => lesson.id);
 
+  // lesson ID alone does not make a lesson unique - combination of lessonId + chapterId + partId does
+  const lessonOrder: { lessonId: Lesson['id']; chapterId?: Chapter['id']; partId?: Part['id'] }[] = [];
+
   const lessonsInRoot = Object.keys(tutorial.parts).length === 0;
 
   // if lessons in root, sort by tutorial.lessons and metadata.lessons
   if (lessonsInRoot) {
-    lessonOrder.push(...getOrder(metadata.lessons, lessonIds));
+    lessonOrder.push(...getOrder(metadata.lessons, lessonIds).map((lessonId) => ({ lessonId })));
   }
 
   // if no lessons in root, sort by parts and their possible chapters
@@ -393,7 +395,7 @@ function sortTutorialLessons(tutorial: Tutorial, metadata: TutorialSchema) {
 
       // all lessons are in part, no chapters
       if (partLessons.length) {
-        lessonOrder.push(...getOrder(part.data.lessons, partLessons));
+        lessonOrder.push(...getOrder(part.data.lessons, partLessons).map((lessonId) => ({ lessonId, partId })));
         continue;
       }
 
@@ -413,14 +415,16 @@ function sortTutorialLessons(tutorial: Tutorial, metadata: TutorialSchema) {
 
         const chapterLessonOrder = getOrder(chapter.data.lessons, chapterLessons);
 
-        lessonOrder.push(...chapterLessonOrder);
+        lessonOrder.push(...chapterLessonOrder.map((lessonId) => ({ lessonId, partId, chapterId })));
       }
     }
   }
 
   // finally apply overall order for lessons
   for (const lesson of tutorial.lessons) {
-    lesson.order = lessonOrder.indexOf(lesson.id);
+    lesson.order = lessonOrder.findIndex(
+      (l) => l.lessonId === lesson.id && l.chapterId === lesson.chapter?.id && l.partId === lesson.part?.id,
+    );
   }
 
   tutorial.lessons.sort((a, b) => a.order - b.order);