⚡️ Run Unit Tests Concurrently

By default, all unit tests run concurrently. We opt-out of this behavior in cases where this is an issue.

Author: gilday

framework/codemodder-testutils/src/main/java/io/codemodder/testutils/CodemodTestMixin.java

@@ -68,21 +68,23 @@ default Stream<DynamicTest> generateTestCases(@TempDir final Path tmpDir) throws
             .toList();
 
     ThrowingConsumer<Path> testExecutor =
-        path ->
-            verifyCodemod(
-                metadata.codemodType(),
-                metadata.renameTestFile(),
-                tmpDir,
-                testResourceDir,
-                path,
-                dependencies,
-                projectProviders,
-                metadata.doRetransformTest(),
-                metadata.expectingFixesAtLines(),
-                metadata.expectingFailedFixesAtLines(),
-                metadata.sonarIssuesJsonFiles(),
-                metadata.sonarHotspotsJsonFiles());
-
+        path -> {
+          // create a new temporary directory for each test case
+          final var tmp = Files.createTempDirectory(tmpDir, "test-case-");
+          verifyCodemod(
+              metadata.codemodType(),
+              metadata.renameTestFile(),
+              tmp,
+              testResourceDir,
+              path,
+              dependencies,
+              projectProviders,
+              metadata.doRetransformTest(),
+              metadata.expectingFixesAtLines(),
+              metadata.expectingFailedFixesAtLines(),
+              metadata.sonarIssuesJsonFiles(),
+              metadata.sonarHotspotsJsonFiles());
+        };
     return DynamicTest.stream(inputStream, displayNameGenerator, testExecutor);
   }
 

gradle/build-plugins/src/main/kotlin/io.codemodder.java.gradle.kts

@@ -15,6 +15,19 @@ spotless {
     }
 }
 
-tasks.withType(Test::class) {
-    useJUnitPlatform()
+testing {
+    @Suppress("UnstableApiUsage")
+    suites {
+        val test by getting(JvmTestSuite::class) {
+            useJUnitJupiter()
+            targets {
+                all {
+                    testTask.configure {
+                        systemProperty("junit.jupiter.execution.parallel.enabled", "true")
+                        systemProperty("junit.jupiter.execution.parallel.mode.default", "concurrent")
+                    }
+                }
+            }
+        }
+    }
 }

plugins/codemodder-plugin-maven/src/test/java/io/codemodder/plugins/maven/MavenProviderTest.java

@@ -1,6 +1,7 @@
 package io.codemodder.plugins.maven;
 
 import static org.assertj.core.api.Assertions.*;
+import static org.junit.jupiter.api.parallel.ExecutionMode.SAME_THREAD;
 import static org.mockito.ArgumentMatchers.*;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
@@ -20,6 +21,7 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
+import org.junit.jupiter.api.parallel.Execution;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
@@ -28,6 +30,7 @@
  * Unit tests for {@link MavenProvider}. We bend over backwards here not to test the pom-operator
  * types.
  */
+@Execution(SAME_THREAD)
 final class MavenProviderTest {
 
   private static class TestPomModifier implements MavenProvider.PomModifier {

plugins/codemodder-plugin-maven/src/test/java/io/codemodder/plugins/maven/operator/RemoteRepositoriesIntegrationTest.java

@@ -1,14 +1,17 @@
 package io.codemodder.plugins.maven.operator;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.parallel.ExecutionMode.SAME_THREAD;
 
 import java.io.*;
 import java.util.*;
 import org.apache.commons.lang3.SystemUtils;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.parallel.Execution;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+@Execution(SAME_THREAD)
 final class RemoteRepositoriesIntegrationTest {
   private static final Logger LOGGER =
       LoggerFactory.getLogger(RemoteRepositoriesIntegrationTest.class);