Add jest and a simple test example

.github/workflows/continuous-integration.yml

@@ -130,3 +130,15 @@ jobs:
         run: "npm ci"
       - name: Run ESLint
         run: "npm run lint"
+
+  testing:
+    runs-on: "ubuntu-latest"
+    steps:
+      - uses: "actions/checkout@v3"
+      - uses: "actions/setup-node@v3"
+        with:
+          check-latest: true
+      - name: "Install node modules"
+        run: "npm ci"
+      - name: Run Jest
+        run: "npm run test"

Dockerfile

@@ -4,7 +4,7 @@ RUN mkdir -p /usr/local/source
 WORKDIR /usr/local/source
 COPY package*.json ./
 COPY tsconfig.json ./
-COPY webpack.config.js ./
+COPY webpack.config.ts ./
 RUN npm ci
 COPY ./src ./src
 RUN npm run build

jest.config.ts

@@ -0,0 +1,11 @@
+// eslint-disable-next-line node/no-unpublished-import
+import {Config} from 'jest';
+
+const config: Config = {
+    reporters       : [ 'default', 'github-actions' ],
+    transform       : {'^.+\\.ts?$': 'ts-jest'},
+    testEnvironment : 'node',
+    testRegex       : '/src/.*\\.spec\\.ts$',
+};
+
+export default config;