Enable NullAway in junit-platform-suite-engine

Author: marcphilipp

junit-platform-suite-engine/junit-platform-suite-engine.gradle.kts

@@ -1,5 +1,6 @@
 plugins {
 	id("junitbuild.java-library-conventions")
+	id("junitbuild.java-nullability-conventions")
 }
 
 description = "JUnit Platform Suite Engine"
@@ -10,6 +11,7 @@ dependencies {
 	api(projects.junitPlatformSuiteApi)
 
 	compileOnlyApi(libs.apiguardian)
+	compileOnly(libs.jspecify)
 
 	implementation(projects.junitPlatformSuiteCommons)
 

junit-platform-suite-engine/src/main/java/module-info.java

@@ -8,13 +8,16 @@
  * https://www.eclipse.org/legal/epl-v20.html
  */
 
+import org.jspecify.annotations.NullMarked;
+
 /**
  * Provides a {@link org.junit.platform.engine.TestEngine} for running
  * declarative test suites.
  *
  * @since 1.8
  * @provides org.junit.platform.engine.TestEngine
  */
+@NullMarked
 module org.junit.platform.suite.engine {
 	requires static org.apiguardian.api;
 	requires org.junit.platform.suite.api;

junit-platform-suite-engine/src/main/java/org/junit/platform/suite/engine/SuiteTestDescriptor.java

@@ -10,6 +10,7 @@
 
 package org.junit.platform.suite.engine;
 
+import static java.util.Objects.requireNonNull;
 import static java.util.function.Predicate.isEqual;
 import static java.util.stream.Collectors.joining;
 import static org.junit.platform.commons.support.AnnotationSupport.findAnnotation;
@@ -21,6 +22,7 @@
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 
+import org.jspecify.annotations.Nullable;
 import org.junit.platform.commons.JUnitException;
 import org.junit.platform.commons.support.ReflectionSupport;
 import org.junit.platform.commons.util.Preconditions;
@@ -71,7 +73,10 @@ final class SuiteTestDescriptor extends AbstractTestDescriptor {
 	private final Class<?> suiteClass;
 	private final LifecycleMethods lifecycleMethods;
 
+	@Nullable
 	private LauncherDiscoveryResult launcherDiscoveryResult;
+
+	@Nullable
 	private SuiteLauncher launcher;
 
 	SuiteTestDescriptor(UniqueId id, Class<?> suiteClass, ConfigurationParameters configurationParameters,
@@ -174,6 +179,7 @@ private void executeBeforeSuiteMethods(ThrowableCollector throwableCollector) {
 		}
 	}
 
+	@Nullable
 	private TestExecutionSummary executeTests(EngineExecutionListener parentEngineExecutionListener,
 			NamespacedHierarchicalStore<Namespace> requestLevelStore, ThrowableCollector throwableCollector) {
 		if (throwableCollector.isNotEmpty()) {
@@ -183,9 +189,9 @@ private TestExecutionSummary executeTests(EngineExecutionListener parentEngineEx
 		// #2838: The discovery result from a suite may have been filtered by
 		// post discovery filters from the launcher. The discovery result should
 		// be pruned accordingly.
-		LauncherDiscoveryResult discoveryResult = this.launcherDiscoveryResult.withRetainedEngines(
+		LauncherDiscoveryResult discoveryResult = requireNonNull(this.launcherDiscoveryResult).withRetainedEngines(
 			getChildren()::contains);
-		return launcher.execute(discoveryResult, parentEngineExecutionListener, requestLevelStore);
+		return requireNonNull(launcher).execute(discoveryResult, parentEngineExecutionListener, requestLevelStore);
 	}
 
 	private void executeAfterSuiteMethods(ThrowableCollector throwableCollector) {
@@ -194,12 +200,13 @@ private void executeAfterSuiteMethods(ThrowableCollector throwableCollector) {
 		}
 	}
 
-	private TestExecutionResult computeTestExecutionResult(TestExecutionSummary summary,
+	private TestExecutionResult computeTestExecutionResult(@Nullable TestExecutionSummary summary,
 			ThrowableCollector throwableCollector) {
-		if (throwableCollector.isNotEmpty()) {
-			return TestExecutionResult.failed(throwableCollector.getThrowable());
+		var throwable = throwableCollector.getThrowable();
+		if (throwable != null) {
+			return TestExecutionResult.failed(throwable);
 		}
-		if (failIfNoTests && summary.getTestsFoundCount() == 0) {
+		if (failIfNoTests && requireNonNull(summary).getTestsFoundCount() == 0) {
 			return TestExecutionResult.failed(new NoTestsDiscoveredException(suiteClass));
 		}
 		return TestExecutionResult.successful();