feat(tests): integrate Playwright and Vitest for testing, add CI pipeline, and update dependencies

- Added Playwright configuration for end-to-end testing.
- Integrated Vitest for unit testing with setup files.
- Updated package.json scripts for testing commands.
- Created CI pipeline for automated testing and builds.
- Added various test cases for components and pages.
- Updated .gitignore to exclude Playwright and coverage.
- Enhanced ModsList component with additional class for styling.

.github/workflows/ci-pipeline.yml

@@ -0,0 +1,109 @@
+name: CI Pipeline
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+jobs:
+  setup:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: lts/*
+      - name: Cache node_modules
+        id: cache-deps
+        uses: actions/cache@v4
+        with:
+          path: |
+            node_modules
+            ~/.cache/ms-playwright
+          key: ${{ runner.os }}-node-${{ hashFiles('package-lock.json') }}
+      - name: Install dependencies
+        run: npm ci
+      - name: Install Playwright Browsers
+        run: npx playwright install --with-deps
+
+  build-check:
+    runs-on: ubuntu-latest
+    needs: setup
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+      - name: Restore node_modules from cache
+        uses: actions/cache@v4
+        with:
+          path: |
+            node_modules
+            ~/.cache/ms-playwright
+          key: ${{ runner.os }}-node-${{ hashFiles('package-lock.json') }}
+      - name: Verify npm installation
+        run: npm --version
+      - name: Build project
+        run: npm run build
+
+  biome:
+    runs-on: ubuntu-latest
+    needs: setup
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+      - name: Restore node_modules from cache
+        uses: actions/cache@v4
+        with:
+          path: |
+            node_modules
+            ~/.cache/ms-playwright
+          key: ${{ runner.os }}-node-${{ hashFiles('package-lock.json') }}
+      - name: Run Biome check
+        run: npx biome check ./src
+
+  vitest:
+    runs-on: ubuntu-latest
+    needs: setup
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: lts/*
+      - name: Restore node_modules from cache
+        uses: actions/cache@v4
+        with:
+          path: |
+            node_modules
+            ~/.cache/ms-playwright
+          key: ${{ runner.os }}-node-${{ hashFiles('package-lock.json') }}
+      - name: Run Vitest tests
+        run: npx vitest run
+
+  playwright:
+    runs-on: ubuntu-latest
+    needs: setup
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: lts/*
+      - name: Restore node_modules from cache
+        uses: actions/cache@v4
+        with:
+          path: |
+            node_modules
+            ~/.cache/ms-playwright
+          key: ${{ runner.os }}-node-${{ hashFiles('package-lock.json') }}
+      - name: Run Playwright tests
+        run: npx playwright test
+      - uses: actions/upload-artifact@v4
+        if: ${{ !cancelled() }}
+        with:
+          name: playwright-report
+          path: playwright-report/
+          retention-days: 30

.github/workflows/prbuildcheck.yml

@@ -1,28 +0,0 @@
-name: PR Build Check
-on:
-  pull_request:
-    types: [opened, synchronize, reopened]
-
-jobs:
-  upload:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
-
-      - name: Setup Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: 22
-
-      - name: Verify npm installation
-        run: npm --version
-
-      - name: Install dependencies
-        run: npm install --no-frozen-lockfile
-
-      - name: Run Biome check
-        run: npx biome check ./src
-
-      - name: Build project
-        run: npm run build

.gitignore

@@ -22,3 +22,11 @@ npm-debug.log*
 
 # jetbrains setting folder
 .idea/
+
+# Playwright
+/test-results/
+/playwright-report/
+/blob-report/
+/playwright/.cache/
+
+/coverage

package.json

@@ -11,7 +11,9 @@
     "astro": "astro",
     "lint": "biome lint ./src",
     "format": "biome format ./src",
-    "prepare": "husky"
+    "prepare": "husky",
+    "test": "npx vitest run",
+    "test:coverage": "npx vitest --coverage"
   },
   "dependencies": {
     "@astrojs/check": "^0.9.4",
@@ -40,11 +42,24 @@
   },
   "devDependencies": {
     "@biomejs/biome": "^1.9.4",
+    "@playwright/test": "^1.52.0",
+    "@testing-library/jest-dom": "^6.6.3",
+    "@testing-library/user-event": "^14.6.1",
+    "@types/jsdom": "^21.1.7",
+    "@types/node": "^22.15.18",
+    "@vitest/coverage-istanbul": "^3.1.3",
+    "@vitest/ui": "^3.1.3",
     "husky": "^9.1.7",
+    "jsdom": "^26.1.0",
     "lint-staged": "^15.2.7",
+    "text-encoding": "^0.7.0",
+    "vite-tsconfig-paths": "^5.1.4",
+    "vitest": "^3.1.3",
     "wrangler": "^3.94.0"
   },
   "lint-staged": {
-    "src/**/*.{ts,tsx,astro,js,jsx}": ["biome check --write ./src"]
+    "src/**/*.{ts,tsx,astro,js,jsx}": [
+      "biome check --write ./src"
+    ]
   }
 }

playwright.config.ts

@@ -0,0 +1,72 @@
+import { defineConfig, devices } from '@playwright/test';
+
+/**
+ * Read environment variables from file.
+ * https://github.com/motdotla/dotenv
+ */
+// import dotenv from 'dotenv';
+// import path from 'path';
+// dotenv.config({ path: path.resolve(__dirname, '.env') });
+
+/**
+ * See https://playwright.dev/docs/test-configuration.
+ */
+export default defineConfig({
+  testDir: './src/tests',
+  testIgnore: ['**.test.ts'],
+  fullyParallel: true,
+  forbidOnly: !!process.env.CI,
+  retries: process.env.CI ? 2 : 0,
+  /* Opt out of parallel tests on CI. */
+  workers: process.env.CI ? 1 : undefined,
+  reporter: 'html',
+  use: {
+    baseURL: 'http://127.0.0.1:3000',
+    trace: 'on-first-retry',
+  },
+
+  /* Configure projects for major browsers */
+  projects: [
+    {
+      name: 'chromium',
+      use: { ...devices['Desktop Chrome'] },
+    },
+
+    {
+      name: 'firefox',
+      use: { ...devices['Desktop Firefox'] },
+    },
+
+    {
+      name: 'webkit',
+      use: { ...devices['Desktop Safari'] },
+    },
+
+    /* Test against mobile viewports. */
+    // {
+    //   name: 'Mobile Chrome',
+    //   use: { ...devices['Pixel 5'] },
+    // },
+    // {
+    //   name: 'Mobile Safari',
+    //   use: { ...devices['iPhone 12'] },
+    // },
+
+    /* Test against branded browsers. */
+    // {
+    //   name: 'Microsoft Edge',
+    //   use: { ...devices['Desktop Edge'], channel: 'msedge' },
+    // },
+    // {
+    //   name: 'Google Chrome',
+    //   use: { ...devices['Desktop Chrome'], channel: 'chrome' },
+    // },
+  ],
+
+  /* Run your local dev server before starting the tests */
+  webServer: {
+    command: 'npm run dev',
+    url: 'http://127.0.0.1:3000',
+    reuseExistingServer: !process.env.CI,
+  },
+});

src/components/ModsList.tsx

@@ -196,7 +196,7 @@ export default function ModsList({ allMods, locale }: ModsListProps) {
         {paginatedMods.length > 0 ? (
           paginatedMods.map((mod) => (
             <a
-              className="flex w-full flex-col gap-4 border-transparent transition-colors duration-100 hover:opacity-90"
+              className="mod-card flex w-full flex-col gap-4 border-transparent transition-colors duration-100 hover:opacity-90"
               href={`/mods/${mod.id}`}
               key={mod.id}
             >

src/components/download/DownloadScript.astro

@@ -1,105 +0,0 @@
-<script>
-  // Handle platform selection
-  const platformButtons = document.querySelectorAll('.platform-selector')
-  const platformSections = document.querySelectorAll('.platform-section')
-
-  // Function to detect OS and select appropriate platform
-  function detectOS() {
-    const userAgent = window.navigator.userAgent
-    let detectedOS = 'mac' // Default to macOS
-
-    if (userAgent.indexOf('Windows') !== -1) {
-      detectedOS = 'windows'
-    } else if (userAgent.indexOf('Linux') !== -1) {
-      detectedOS = 'linux'
-    }
-
-    return detectedOS
-  }
-
-  // Initialize platform based on user's OS
-  async function initializePlatform() {
-    const detectedOS = detectOS()
-    selectPlatform(detectedOS)
-  }
-
-  // Function to select a platform
-  async function selectPlatform(platform: string) {
-    // Update button styling
-    platformButtons.forEach((button) => {
-      const buttonPlatform = button.getAttribute('data-platform')
-      if (buttonPlatform === platform) {
-        button.setAttribute('data-active', 'true')
-      } else {
-        button.setAttribute('data-active', 'false')
-      }
-    })
-
-    // Show/hide platform sections
-    platformSections.forEach((section) => {
-      if (section.id === `${platform}-downloads`) {
-        section.setAttribute('data-active', 'true')
-      } else {
-        section.setAttribute('data-active', 'false')
-      }
-    })
-  }
-
-  // Handle platform button clicks
-  platformButtons.forEach((button) => {
-    button.addEventListener('click', () => {
-      const platform = button.getAttribute('data-platform') ?? ''
-      selectPlatform(platform)
-    })
-  })
-
-  // Check for twilight mode
-  async function checkTwilightMode() {
-    const urlParams = new URLSearchParams(window.location.search)
-    const isTwilight = urlParams.has('twilight')
-
-    if (isTwilight) {
-      const twilightInfoElem = document.getElementById('twilight-info')
-      twilightInfoElem?.setAttribute('data-twilight', 'true')
-
-      // Update UI to show twilight mode with animation
-      const titleElem = document.getElementById('download-title')
-      if (titleElem) {
-        const zenText = titleElem.innerHTML
-        titleElem.innerHTML = zenText.replace('Zen', 'Twilight')
-      }
-
-      const tags = document.querySelectorAll('.release-type-tag')
-      tags.forEach((tag) => {
-        tag.innerHTML = tag.innerHTML.replace('Beta', 'Twilight')
-      })
-
-      // Apply twilight mode to all relevant elements
-      const coralElements = document.querySelectorAll(
-        '.download-browser-logo, .release-type-tag, .decorative-gradient, .download-link, .download-arrow-icon, .download-card__icon, .checksum-icon-btn, .copy-btn',
-      )
-      coralElements.forEach((element) => {
-        element.setAttribute('data-twilight', 'true')
-      })
-
-      // Replace all download links with twilight versions
-      const downloadLinks = document.querySelectorAll('a.download-link')
-      downloadLinks.forEach((link) => {
-        if (!link.id.includes('beta')) {
-          const href = link.getAttribute('href')
-          if (href && href.includes('/latest/download/')) {
-            const twilightHref = href.replace(
-              '/latest/download/',
-              '/download/twilight/',
-            )
-            link.setAttribute('href', twilightHref)
-          }
-        }
-      })
-    }
-  }
-
-  // Initialize the page
-  initializePlatform()
-  checkTwilightMode()
-</script>

src/pages/[...locale]/download.astro

@@ -1,6 +1,5 @@
 ---
 import Description from '~/components/Description.astro'
-import DownloadScript from '~/components/download/DownloadScript.astro'
 import PlatformDownload from '~/components/download/PlatformDownload.astro'
 import { getReleasesWithChecksums } from '~/components/download/release-data.astro'
 import Layout from '~/layouts/Layout.astro'
@@ -33,8 +32,6 @@ const platformNames = download.platformNames
 const platformDescriptions = download.platformDescriptions
 ---
 
-<DownloadScript />
-
 <Layout title={layout.download.title} description={layout.download.description}>
   <main class="flex min-h-screen flex-col px-6 data-[os='windows']:bg-zen-blue">
     <div class="container relative mx-auto py-12">
@@ -231,3 +228,109 @@ const platformDescriptions = download.platformDescriptions
     width: 3rem;
   }
 </style>
+
+<script>
+  // Handle platform selection
+  const platformButtons = document.querySelectorAll('.platform-selector')
+  const platformSections = document.querySelectorAll('.platform-section')
+
+  // Function to detect OS and select appropriate platform
+  function detectOS() {
+    const userAgent = window.navigator.userAgent
+    let detectedOS = 'mac' // Default to macOS
+
+    if (userAgent.indexOf('Windows') !== -1) {
+      detectedOS = 'windows'
+    } else if (userAgent.indexOf('Linux') !== -1) {
+      detectedOS = 'linux'
+    }
+
+    return detectedOS
+  }
+
+  // Initialize platform based on user's OS
+  async function initializePlatform() {
+    const detectedOS = detectOS()
+    selectPlatform(detectedOS)
+  }
+
+  // Function to select a platform
+  async function selectPlatform(platform: string) {
+    // Update button styling
+    platformButtons.forEach((button) => {
+      const buttonPlatform = button.getAttribute('data-platform')
+      if (buttonPlatform === platform) {
+        button.setAttribute('data-active', 'true')
+      } else {
+        button.setAttribute('data-active', 'false')
+      }
+    })
+
+    // Show/hide platform sections
+    platformSections.forEach((section) => {
+      if (section.id === `${platform}-downloads`) {
+        section.setAttribute('data-active', 'true')
+      } else {
+        section.setAttribute('data-active', 'false')
+      }
+    })
+  }
+
+  // Handle platform button clicks
+  platformButtons.forEach((button) => {
+    button.addEventListener('click', () => {
+      const platform = button.getAttribute('data-platform') ?? ''
+      selectPlatform(platform)
+    })
+  })
+
+  // Check for twilight mode
+  async function checkTwilightMode() {
+    const urlParams = new URLSearchParams(window.location.search)
+    const isTwilight = urlParams.has('twilight')
+
+    if (isTwilight) {
+      const twilightInfoElem = document.getElementById('twilight-info')
+      twilightInfoElem?.setAttribute('data-twilight', 'true')
+
+      // Update UI to show twilight mode with animation
+      const titleElem = document.getElementById('download-title')
+      if (titleElem) {
+        const zenText = titleElem.innerHTML
+        titleElem.innerHTML = zenText.replace('Zen', 'Twilight')
+      }
+
+      const tags = document.querySelectorAll('.release-type-tag')
+      tags.forEach((tag) => {
+        tag.innerHTML = tag.innerHTML.replace('Beta', 'Twilight')
+      })
+
+      // Apply twilight mode to all relevant elements
+      const coralElements = document.querySelectorAll(
+        '.download-browser-logo, .release-type-tag, .decorative-gradient, .download-link, .download-arrow-icon, .download-card__icon, .checksum-icon-btn, .copy-btn',
+      )
+      coralElements.forEach((element) => {
+        element.setAttribute('data-twilight', 'true')
+      })
+
+      // Replace all download links with twilight versions
+      const downloadLinks = document.querySelectorAll('a.download-link')
+      downloadLinks.forEach((link) => {
+        if (!link.id.includes('beta')) {
+          const href = link.getAttribute('href')
+          if (href && href.includes('/latest/download/')) {
+            const twilightHref = href.replace(
+              '/latest/download/',
+              '/download/twilight/',
+            )
+            link.setAttribute('href', twilightHref)
+          }
+        }
+      })
+    }
+  }
+
+  // Initialize the page
+  initializePlatform()
+  checkTwilightMode()
+</script>

src/tests/components/Button.test.ts

@@ -0,0 +1,101 @@
+import { experimental_AstroContainer as AstroContainer } from 'astro/container'
+import { beforeEach, describe, expect, it } from 'vitest'
+import Button from '~/components/Button.astro'
+
+describe('<Button />', () => {
+  let container: Awaited<ReturnType<typeof AstroContainer.create>>
+
+  beforeEach(async () => {
+    container = await AstroContainer.create()
+  })
+
+  describe('as <button>', () => {
+    it('renders default <button> with slot', async () => {
+      const result = await container.renderToString(Button, {
+        props: {},
+        slots: { default: 'Click me' },
+      })
+      expect(result).toContain('<button')
+      expect(result).toContain('Click me')
+    })
+
+    it.each([
+      ['isPrimary', { isPrimary: true }, 'bg-dark'],
+      ['isAlert', { isAlert: true }, 'bg-red-300'],
+      ['isBordered', { isBordered: true }, 'border-2'],
+    ])('applies %s style', async (_label, propObj, expectedClass) => {
+      const result = await container.renderToString(Button, {
+        props: { ...propObj },
+        slots: { default: 'Test' },
+      })
+      expect(result).toContain('<button')
+      expect(result).toContain(expectedClass)
+    })
+
+    it('applies id and extra props', async () => {
+      const result = await container.renderToString(Button, {
+        props: {
+          id: 'my-btn',
+          extra: { 'data-test': 'foo' },
+        },
+        slots: { default: 'Test' },
+      })
+      expect(result).toContain('id="my-btn"')
+      expect(result).toContain('data-test="foo"')
+    })
+  })
+
+  describe('as <a>', () => {
+    it('renders <a> with slot and href', async () => {
+      const result = await container.renderToString(Button, {
+        props: { href: '/link' },
+        slots: { default: 'Go' },
+      })
+      expect(result).toContain('<a')
+      expect(result).toContain('Go')
+      expect(result).toContain('href="/en/link"')
+    })
+
+    it.each([
+      ['isPrimary', { isPrimary: true }, 'bg-dark'],
+      ['isAlert', { isAlert: true }, 'bg-red-300'],
+      ['isBordered', { isBordered: true }, 'border-2'],
+    ])('applies %s style', async (_label, propObj, expectedClass) => {
+      const result = await container.renderToString(Button, {
+        props: { href: '/link', ...propObj },
+        slots: { default: 'Test' },
+      })
+      expect(result).toContain('<a')
+      expect(result).toContain(expectedClass)
+    })
+
+    it('applies id and extra props', async () => {
+      const result = await container.renderToString(Button, {
+        props: {
+          href: '/link',
+          id: 'my-link',
+          extra: { 'data-test': 'bar' },
+        },
+        slots: { default: 'Test' },
+      })
+      expect(result).toContain('id="my-link"')
+      expect(result).toContain('data-test="bar"')
+    })
+  })
+
+  it('applies custom className', async () => {
+    const result = await container.renderToString(Button, {
+      props: { class: 'custom-class' },
+      slots: { default: 'Test' },
+    })
+    expect(result).toContain('custom-class')
+  })
+
+  it('uses locale path for href', async () => {
+    const result = await container.renderToString(Button, {
+      props: { href: '/foo' },
+      slots: { default: 'Test' },
+    })
+    expect(result).toContain('href="/en/foo"')
+  })
+})

src/tests/components/ButtonCard.test.ts

@@ -0,0 +1,47 @@
+import { experimental_AstroContainer as AstroContainer } from 'astro/container'
+import { beforeEach, describe, expect, it } from 'vitest'
+import ButtonCard from '~/components/download/ButtonCard.astro'
+
+describe('<ButtonCard />', () => {
+  let container: Awaited<ReturnType<typeof AstroContainer.create>>
+  beforeEach(async () => {
+    container = await AstroContainer.create()
+  })
+
+  it('renders with required props', async () => {
+    const result = await container.renderToString(ButtonCard, {
+      props: {
+        label: 'Download',
+        href: '/download',
+      },
+    })
+    expect(result).toContain('Download')
+    expect(result).toContain('href="/download"')
+    expect(result).not.toContain('Show SHA-256')
+  })
+
+  it('renders with checksum', async () => {
+    const result = await container.renderToString(ButtonCard, {
+      props: {
+        label: 'Download',
+        href: '/download',
+        checksum: 'sha256sum',
+      },
+    })
+    expect(result).toContain('Show SHA-256')
+    expect(result).toContain('sha256sum')
+    expect(result).toContain('Copy')
+  })
+
+  it('renders with variant', async () => {
+    const result = await container.renderToString(ButtonCard, {
+      props: {
+        label: 'Download',
+        href: '/download',
+        variant: 'flathub',
+      },
+    })
+    expect(result).toContain('Download')
+    expect(result).toContain('Beta')
+  })
+})

src/tests/components/PlatformDownload.test.ts

@@ -0,0 +1,88 @@
+import { experimental_AstroContainer as AstroContainer } from 'astro/container'
+import { beforeEach, describe, expect, it } from 'vitest'
+import PlatformDownload from '~/components/download/PlatformDownload.astro'
+
+const mockIcon = ['<svg></svg>']
+const mockReleases = {
+  universal: { label: 'Universal', link: '/universal', checksum: 'abc123' },
+  x86_64: { label: 'x86_64', link: '/x86_64', checksum: 'def456' },
+  arm64: { label: 'ARM64', link: '/arm64', checksum: 'ghi789' },
+  flathub: { all: { label: 'Flathub', link: '/flathub' } },
+}
+
+describe('<PlatformDownload />', () => {
+  let container: Awaited<ReturnType<typeof AstroContainer.create>>
+  beforeEach(async () => {
+    container = await AstroContainer.create()
+  })
+
+  it('renders mac platform', async () => {
+    const result = await container.renderToString(PlatformDownload, {
+      props: {
+        platform: 'mac',
+        icon: mockIcon,
+        title: 'Mac Title',
+        description: 'Mac Desc',
+        releases: mockReleases,
+      },
+    })
+    expect(result).toContain('Mac Title')
+    expect(result).toContain('Mac Desc')
+    expect(result).toContain('Universal')
+  })
+
+  it('renders windows platform', async () => {
+    const result = await container.renderToString(PlatformDownload, {
+      props: {
+        platform: 'windows',
+        icon: mockIcon,
+        title: 'Win Title',
+        description: 'Win Desc',
+        releases: mockReleases,
+      },
+    })
+    expect(result).toContain('Win Title')
+    expect(result).toContain('Win Desc')
+    expect(result).toContain('x86_64')
+    expect(result).toContain('ARM64')
+  })
+
+  it('renders linux platform with flathub and tarball', async () => {
+    const linuxReleases = {
+      flathub: { all: { label: 'Flathub', link: '/flathub' } },
+      x86_64: { tarball: { label: 'Tarball x86_64', link: '/tarball-x86_64', checksum: 'sha256' } },
+    }
+    const result = await container.renderToString(PlatformDownload, {
+      props: {
+        platform: 'linux',
+        icon: mockIcon,
+        title: 'Linux Title',
+        description: 'Linux Desc',
+        releases: linuxReleases,
+      },
+    })
+    expect(result).toContain('Linux Title')
+    expect(result).toContain('Linux Desc')
+    expect(result).toContain('Flathub')
+    expect(result).toContain('Tarball')
+    expect(result).toContain('x86_64')
+  })
+
+  it('renders linux platform with all branches', async () => {
+    const linuxReleases = {
+      flathub: { all: { label: 'Flathub', link: '/flathub' } },
+      x86_64: { tarball: { label: 'Tarball x86_64', link: '/tarball-x86_64', checksum: 'sha256' } },
+      arm64: { label: 'ARM64', link: '/arm64', checksum: 'ghi789' },
+    }
+    const result = await container.renderToString(PlatformDownload, {
+      props: {
+        platform: 'linux',
+        icon: mockIcon,
+        title: 'Linux Title',
+        description: 'Linux Desc',
+        releases: linuxReleases,
+      },
+    })
+    expect(result).toContain('ARM64')
+  })
+})

src/tests/components/release-data.test.ts

@@ -0,0 +1,26 @@
+import { describe, expect, it } from 'vitest'
+import { getReleasesWithChecksums } from '~/components/download/release-data.astro'
+
+describe('getReleasesWithChecksums', () => {
+  it('returns correct structure with checksums', () => {
+    const checksums = {
+      'zen.macos-universal.dmg': 'macsum',
+      'zen.installer.exe': 'winsum',
+      'zen.installer-arm64.exe': 'winarmsum',
+      'zen.linux-x86_64.tar.xz': 'linx86sum',
+      'zen-x86_64.AppImage': 'linx86appsum',
+      'zen.linux-aarch64.tar.xz': 'linaarchsum',
+      'zen-aarch64.AppImage': 'linaarchappsum',
+    }
+    const releases = getReleasesWithChecksums(checksums)
+    expect(releases.macos.universal.checksum).toBe('macsum')
+    expect(releases.windows.x86_64.checksum).toBe('winsum')
+    expect(releases.windows.arm64.checksum).toBe('winarmsum')
+    expect(releases.linux.x86_64.tarball.checksum).toBe('linx86sum')
+    expect(releases.linux.x86_64.appImage.checksum).toBe('linx86appsum')
+    expect(releases.linux.aarch64.tarball.checksum).toBe('linaarchsum')
+    expect(releases.linux.aarch64.appImage.checksum).toBe('linaarchappsum')
+    expect(releases.linux.flathub.all.label).toBe('Flathub')
+    expect(releases.linux.flathub.all.link).toBe('https://flathub.org/apps/app.zen_browser.zen')
+  })
+})

src/tests/pages/download.spec.ts

@@ -0,0 +1,67 @@
+import { expect, test } from '@playwright/test'
+import type { BrowserContextOptions, Page } from '@playwright/test'
+
+// Helper to get the platform section by id
+const getPlatformSection = (page: Page, platform: string) =>
+  page.locator(`#${platform}-downloads.platform-section[data-active='true']`)
+
+// Helper to get the platform tab button
+const getPlatformButton = (page: Page, platform: string) =>
+  page.locator(`button.platform-selector[data-platform='${platform}']`)
+
+const platformConfigs: { name: string; userAgent: string; platform: string }[] = [
+  {
+    name: 'windows',
+    userAgent:
+      'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
+    platform: 'Win32',
+  },
+  {
+    name: 'mac',
+    userAgent:
+      'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.1 Safari/605.1.15',
+    platform: 'MacIntel',
+  },
+  {
+    name: 'linux',
+    userAgent: 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
+    platform: 'Linux x86_64',
+  },
+]
+
+for (const { name, userAgent, platform } of platformConfigs) {
+  test(`shows correct default tab for ${name} platform`, async ({ browser }) => {
+    const context = await browser.newContext({
+      userAgent,
+      locale: 'en-US',
+      platform,
+    } as BrowserContextOptions)
+    const page = await context.newPage()
+    await page.goto('/download')
+    await expect(getPlatformSection(page, name)).toBeVisible()
+    await expect(getPlatformButton(page, name)).toHaveAttribute('data-active', 'true')
+    // Other platforms should not be active
+    for (const other of platformConfigs.filter((p) => p.name !== name)) {
+      await expect(getPlatformSection(page, other.name)).toBeHidden()
+      await expect(getPlatformButton(page, other.name)).not.toHaveAttribute('data-active', 'true')
+    }
+    await context.close()
+  })
+}
+
+test.describe('Download page platform detection and tab switching', () => {
+  test('shows correct platform section and tab when switching platforms', async ({ page }) => {
+    await page.goto('/download')
+    const platforms = ['windows', 'mac', 'linux']
+    for (const platform of platforms) {
+      await getPlatformButton(page, platform).click()
+      await expect(getPlatformSection(page, platform)).toBeVisible()
+      await expect(getPlatformButton(page, platform)).toHaveAttribute('data-active', 'true')
+      // other platform sections should be hidden
+      for (const otherPlatform of platforms.filter((p) => p !== platform)) {
+        await expect(getPlatformSection(page, otherPlatform)).toBeHidden()
+        await expect(getPlatformButton(page, otherPlatform)).not.toHaveAttribute('data-active', 'true')
+      }
+    }
+  })
+})

src/tests/pages/mods.spec.ts

@@ -0,0 +1,11 @@
+import { expect, test } from '@playwright/test'
+
+test('clicking back button navigates to previous page', async ({ page }) => {
+  await page.goto('/mods?created=asc')
+  const currentUrl = page.url()
+  const modCards = await page.locator('.mod-card').all()
+  await modCards[0].click()
+  await page.getByRole('button', { name: 'Back' }).click()
+  await page.waitForURL(currentUrl)
+  expect(page.url()).toStrictEqual(currentUrl)
+})

src/tests/pages/routes.spec.ts

@@ -0,0 +1,9 @@
+import { expect, test } from '@playwright/test'
+
+test('all routes do not return 404', async ({ page }) => {
+  const routes = ['/', '/welcome', '/about', '/privacy-policy', '/download', '/donate', '/whatsnew']
+  for (const route of routes) {
+    const response = await page.goto(route)
+    expect(response?.status()).not.toBe(404)
+  }
+})

src/tests/vitest.setup.ts

@@ -0,0 +1,8 @@
+import { vi } from 'vitest'
+import translation from '~/i18n/en/translation.json'
+
+vi.mock('~/utils/i18n', () => ({
+  getLocale: () => 'en',
+  getPath: () => (href: string) => `/en${href}`,
+  getUI: () => translation,
+}))

src/utils/githubChecksums.ts

@@ -3,6 +3,13 @@
  * Returns a mapping from filename to checksum.
  */
 export async function getChecksums() {
+  if (import.meta.env.DEV) {
+    return {
+      'zen.macos-universal.dmg': 'macsum',
+      'zen.installer.exe': 'winsum',
+      'zen.installer-arm64.exe': 'winarmsum',
+    }
+  }
   const res = await fetch('https://api.github.com/repos/zen-browser/desktop/releases/latest', {
     headers: {
       Accept: 'application/vnd.github+json',

tsconfig.json

@@ -5,7 +5,12 @@
     "jsxImportSource": "preact",
     "baseUrl": ".",
     "paths": {
-      "~/*": ["./src/*"]
-    }
+      "~/*": [
+        "./src/*"
+      ]
+    },
+    "types": [
+      "@vitest/browser/providers/playwright"
+    ]
   }
 }

vitest.config.ts

@@ -0,0 +1,12 @@
+/// <reference types="vitest" />
+import { getViteConfig } from 'astro/config';
+
+export default getViteConfig({
+  test: {
+    setupFiles: ['./src/tests/vitest.setup.ts'],
+    coverage: {
+      provider: 'istanbul',
+      reporter: ['text', 'html'],
+    },
+  },
+});