Add GitHub Actions CI workflow for automated testing

.github/workflows/ci.yml

@@ -0,0 +1,38 @@
+name: CI
+
+on:
+  push:
+    branches: [ master, main ]
+  pull_request:
+    branches: [ master, main ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up JDK 21
+      uses: actions/setup-java@v4
+      with:
+        java-version: '21'
+        distribution: 'temurin'
+
+    - name: Setup Gradle
+      uses: gradle/actions/setup-gradle@v3
+      with:
+        cache-cleanup: on-success
+
+    - name: Make gradlew executable
+      run: chmod +x gradlew
+
+    - name: Run tests
+      run: ./gradlew test
+
+    - name: Upload test results
+      uses: actions/upload-artifact@v4
+      if: always()
+      with:
+        name: test-results
+        path: build/reports/tests/test/

build.gradle

@@ -30,9 +30,14 @@ dependencies {
     testImplementation('org.spockframework:spock-core:2.4-M6-groovy-4.0') {
         exclude group: 'org.codehaus.groovy'
     }
+
+    // Mocking libraries required by Spock for Java class mocking
+    testImplementation 'net.bytebuddy:byte-buddy:1.14.8'
+    testImplementation 'org.mockito:mockito-core:5.7.0'
+    testImplementation 'org.objenesis:objenesis:3.3'
 }
 
-version = '1.3'
+version = '1.4-SNAPSHOT'
 group = 'com.xlson.groovycsv'
 
 sourceSets {
@@ -95,3 +100,7 @@ def isSetupForDeployToMavenCentral() {
 }
 
 // TODO: Update to use maven-publish plugin syntax
+
+test {
+    useJUnitPlatform()
+}