feat: Integrate Jest for JavaScript testing with CI setup (#28)

Co-authored-by: sourcery-ai[bot] <sourcery-ai[bot]@users.noreply.github.com>
Co-authored-by: Fabian Braun <[email protected]>

.github/workflows/frontend.yml

@@ -18,5 +18,5 @@ jobs:
       run: npm install
     - name: Build bundles
       run: webpack --mode=production
-    # - name: Run gulp
-    #   run: gulp ci
+    - name: Run jest
+      run: npx jest

.gitignore

@@ -1,3 +1,5 @@
+# Jest coverage
+/coverage
 *.py[cod]
 *$py.class
 *.egg-info

babel.config.js

@@ -0,0 +1,9 @@
+module.exports = {
+  presets: [
+    ['@babel/preset-env', {
+      targets: {
+        node: 'current',
+      },
+    }],
+  ],
+};

jest.config.js

@@ -0,0 +1,16 @@
+module.exports = {
+  testEnvironment: 'jsdom',
+  setupFilesAfterEnv: ['<rootDir>/tests/js/setup-tests.js'],
+  moduleNameMapper: {
+    '\\.(css|less|scss|sass)$': '<rootDir>/tests/js/__mocks__/styleMock.js',
+    '\\.(gif|ttf|eot|svg)$': '<rootDir>/tests/js/__mocks__/fileMock.js'
+  },
+  testMatch: [
+    '**/tests/js/**/*.test.js'
+  ],
+  coverageDirectory: 'coverage',
+  collectCoverageFrom: [
+    'private/js/**/*.js',
+    '!**/node_modules/**'
+  ]
+};