Add Jest tests with CI runs (#107)

* add Jest setup and configuration for testing; implement user-related tests with mocks

* Add GHA for tests

* Remove interactive auth

* Add neon auth step

* Try with env in action file

* Use new Neon CLI

* Adjust connection string comment

* Update branch cleanup command

.github/workflows/test.yml

@@ -0,0 +1,60 @@
+name: Tests
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    env:
+      BRANCH_NAME: ci-${{ github.run_id }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Install Neon CLI
+        run: npm install -g neonctl
+
+      - name: Create database branch
+        env:
+          NEON_API_KEY: ${{ secrets.NEON_API_KEY }}
+        run: |
+          neonctl branches create --name ${{ env.BRANCH_NAME }} --project-id ${{ secrets.NEON_PROJECT_ID }} --parent test
+          echo "DATABASE_URL=$(neonctl connection-string --branch-name ${{ env.BRANCH_NAME }} --project-id ${{ secrets.NEON_PROJECT_ID }} --prisma)" >> $GITHUB_ENV
+
+      - name: Generate Prisma Client
+        run: npx prisma generate
+
+      - name: Apply Migrations
+        if: github.event_name == 'pull_request'
+        run: |
+          # Reset database to last known good state
+          npx prisma migrate reset --force
+          # Apply any new migrations
+          npx prisma migrate deploy
+        env:
+          DATABASE_URL: ${{ env.DATABASE_URL }}
+
+      - name: Run tests
+        run: npm test
+        env:
+          DATABASE_URL: ${{ env.DATABASE_URL }}
+
+      - name: Cleanup database branch
+        env:
+          NEON_API_KEY: ${{ secrets.NEON_API_KEY }}
+        if: always()
+        run: |
+          neonctl branches delete ${{ env.BRANCH_NAME }} --project-id ${{ secrets.NEON_PROJECT_ID }}

jest.config.js

@@ -0,0 +1,27 @@
+const nextJest = require('next/jest')
+
+const createJestConfig = nextJest({
+  // Provide the path to your Next.js app to load next.config.js and .env files in your test environment
+  dir: './',
+})
+
+// Add any custom config to be passed to Jest
+const customJestConfig = {
+  setupFilesAfterEnv: ['<rootDir>/jest.setup.js'],
+  testEnvironment: 'jest-environment-jsdom',
+  moduleNameMapper: {
+    // Handle module aliases (if you're using them in your Next.js project)
+    '^@/(.*)$': '<rootDir>/src/$1',
+  },
+  testPathIgnorePatterns: ['<rootDir>/cypress/'],
+  collectCoverage: true,
+  collectCoverageFrom: [
+    'src/**/*.{js,jsx,ts,tsx}',
+    '!src/**/*.d.ts',
+    '!src/**/_*.{js,jsx,ts,tsx}',
+    '!src/**/*.stories.{js,jsx,ts,tsx}',
+  ],
+}
+
+// createJestConfig is exported this way to ensure that next/jest can load the Next.js config which is async
+module.exports = createJestConfig(customJestConfig)

jest.setup.js

@@ -0,0 +1,32 @@
+import '@testing-library/jest-dom'
+
+// Mock next/navigation
+jest.mock('next/navigation', () => ({
+  useRouter: () => ({
+    push: jest.fn(),
+    replace: jest.fn(),
+    refresh: jest.fn(),
+  }),
+  useSearchParams: () => ({
+    get: jest.fn(),
+  }),
+}))
+
+// Mock clerk/nextjs
+jest.mock('@clerk/nextjs', () => ({
+  auth: () => ({
+    userId: 'test-user-id',
+  }),
+  currentUser: () => ({
+    id: 'test-user-id',
+    email: '[email protected]',
+  }),
+}))
+
+// Mock PostHog
+jest.mock('@/app/posthog', () => ({
+  __esModule: true,
+  default: () => ({
+    capture: jest.fn(),
+  }),
+}))