Annotate nullability in org.junit.platform.commons.test

Author: marcphilipp

junit-platform-commons/src/testFixtures/java/org/junit/platform/commons/test/ConcurrencyTestingUtils.java

@@ -21,6 +21,8 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 
+import org.jspecify.annotations.Nullable;
+
 public class ConcurrencyTestingUtils {
 
 	public static void executeConcurrently(int threads, Runnable action) throws Exception {
@@ -30,7 +32,7 @@ public static void executeConcurrently(int threads, Runnable action) throws Exce
 		});
 	}
 
-	public static <T> List<T> executeConcurrently(int threads, Callable<T> action) throws Exception {
+	public static <T> List<T> executeConcurrently(int threads, Callable<@Nullable T> action) throws Exception {
 		ExecutorService executorService = Executors.newFixedThreadPool(threads);
 		try {
 			CountDownLatch latch = new CountDownLatch(threads);

junit-platform-commons/src/testFixtures/java/org/junit/platform/commons/test/package-info.java

@@ -0,0 +1,5 @@
+
+@NullMarked
+package org.junit.platform.commons.test;
+
+import org.jspecify.annotations.NullMarked;