[Meta] Add frontend component testing

eslint.config.mjs

@@ -263,5 +263,17 @@ export default tseslint.config(
       'no-promise-executor-return': 'off',
     },
   },
+
+  // Frontend tests
+  {
+    files: ['services/frontend/tests/**/*.{ts,tsx}', "services/frontend/playwright/**/*.{ts,tsx}", 'services/frontend/playwright-ct.config.ts'],
+    rules: {
+      'import-x/no-extraneous-dependencies': 'off',
+      'import-x/no-unused-modules': 'off',
+      'import-x/no-default-export': 'off',
+      'react/jsx-filename-extension': 'off',
+    },
+  },
+
   eslintPluginPrettierRecommended // This must be the last plugin so it can override other configs
 )

services/frontend/.gitignore

@@ -3,4 +3,12 @@
 .pnp.js
 
 # production
-/build
+/build
+
+# Playwright
+node_modules/
+/test-results/
+/playwright-report/
+/blob-report/
+/playwright/.cache/
+/playwright/.auth/

services/frontend/package.json

@@ -6,7 +6,9 @@
     "start": "vite",
     "build": "tsc --noEmit && NODE_OPTIONS=\"--max-old-space-size=4096\" vite build",
     "preview": "vite preview",
-    "tsc": "tsc"
+    "tsc": "tsc",
+    "test:unit": "node --import tsx --test './tests/unit/**/*test.ts' --test-reporter spec --test-force-exit",
+    "test:component": "playwright test -c playwright-ct.config.ts"
   },
   "dependencies": {
     "@emotion/react": "^11.14.0",
@@ -37,11 +39,13 @@
     "xlsx": "https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz"
   },
   "devDependencies": {
+    "@playwright/experimental-ct-react": "1.61.0",
     "@types/lodash-es": "^4.17.12",
     "@types/node": "^24.10.1",
     "@types/react": "^18.3.23",
     "@types/react-dom": "^18.3.7",
     "@vitejs/plugin-react-swc": "^4.2.3",
+    "tsx": "4.22.4",
     "typescript": "^5.9.2",
     "vite": "^7.3.1"
   }

services/frontend/playwright-ct.config.ts

@@ -0,0 +1,57 @@
+import { defineConfig, devices } from '@playwright/experimental-ct-react'
+import path from 'path'
+import { fileURLToPath } from 'url'
+
+/**
+ * See https://playwright.dev/docs/test-configuration.
+ */
+export default defineConfig({
+  testDir: './',
+  /* The base directory, relative to the config file, for snapshot files created with toMatchSnapshot and toHaveScreenshot. */
+  snapshotDir: './__snapshots__',
+  /* Maximum time one test can run for. */
+  timeout: 10 * 1000,
+  /* Run tests in files in parallel */
+  fullyParallel: true,
+  /* Fail the build on CI if you accidentally left test.only in the source code. */
+  forbidOnly: !!process.env.CI,
+  /* Retry on CI only */
+  retries: process.env.CI ? 2 : 0,
+  /* Opt out of parallel tests on CI. */
+  workers: process.env.CI ? 1 : undefined,
+  /* Reporter to use. See https://playwright.dev/docs/test-reporters */
+  reporter: 'html',
+  /* Shared settings for all the projects below. See https://playwright.dev/docs/api/class-testoptions. */
+  use: {
+    /* Collect trace when retrying the failed test. See https://playwright.dev/docs/trace-viewer */
+    trace: 'on-first-retry',
+
+    /* Port to use for Playwright component endpoint. */
+    ctPort: 3100,
+
+    /* Fix import from "@/xyz"*/
+    ctViteConfig: {
+      resolve: {
+        alias: {
+          '@': path.resolve(fileURLToPath(import.meta.url), '../src'),
+        },
+      },
+    },
+  },
+
+  /* Configure projects for major browsers */
+  projects: [
+    {
+      name: 'chromium',
+      use: { ...devices['Desktop Chrome'] },
+    },
+    {
+      name: 'firefox',
+      use: { ...devices['Desktop Firefox'] },
+    },
+    {
+      name: 'webkit',
+      use: { ...devices['Desktop Safari'] },
+    },
+  ],
+})

services/frontend/playwright/index.html

@@ -0,0 +1,12 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Testing Page</title>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script type="module" src="./index.tsx"></script>
+  </body>
+</html>

services/frontend/playwright/index.tsx

@@ -0,0 +1,2 @@
+// Import styles, initialize component theme here.
+// import '../src/common.css';

services/frontend/tests/components/Footer/index.spec.tsx

@@ -0,0 +1,9 @@
+import { test, expect } from '@playwright/experimental-ct-react'
+import { Footer } from '../../../src/components/Footer/index'
+
+test('should work', async ({ mount }) => {
+  const component = await mount(<Footer />)
+  await expect(component).toContainText('Oodikone')
+  await expect(component).toContainText('Build')
+  await expect(component).toContainText('Version dev')
+})

services/frontend/tsconfig.json

@@ -28,6 +28,6 @@
     }
   },
   "references": [{ "path": "./tsconfig.node.json" }],
-  "include": ["src"],
+  "include": ["src", "tests", "./playwright-ct.config.ts", "playwright"],
   "exclude": ["../backend"]
 }