Additional tests for IS query targeting plural paths.

Also needed to suppress a nullable probe false positive.

Original Pull Request: #4182

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/JpaResultConverters.java

@@ -47,7 +47,8 @@ public final class JpaResultConverters {
 	 *
 	 * @author Thomas Darimont
 	 */
-	public enum BlobToByteArrayConverter implements Converter<Blob, byte[]> {
+	@SuppressWarnings("NullAway")
+	public enum BlobToByteArrayConverter implements Converter<Blob, byte @Nullable[]> {
 
 		INSTANCE;
 

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/UserRepositoryTests.java

@@ -922,6 +922,8 @@ class UserRepositoryTests {
 		assertThat(repository.existsById(secondUser.getId())).isTrue();
 		assertThat(repository.existsById(thirdUser.getId())).isTrue();
 		assertThat(repository.existsById(fourthUser.getId())).isTrue();
+
+		em.clear();
 	}
 
 	private static <T> void assertSameElements(Collection<T> first, Collection<T> second) {
@@ -2914,10 +2916,8 @@ class UserRepositoryTests {
 	@Test // GH-4172
 	void findByFluentSpecificationWithDtoProjectionJoins() {
 
-		flushTestUsers();
 		firstUser.setManager(secondUser);
-		em.persist(firstUser);
-		em.flush();
+		flushTestUsers();
 
 		record MyProjection(String name, int age, boolean active, String managerName, int managerAge) {
 		}
@@ -3694,6 +3694,31 @@ class UserRepositoryTests {
 		assertThat(result).containsOnly(firstUser, secondUser);
 	}
 
+	@Test // GH-4179
+	void countOnCollectionPropertyWithIs() {
+
+		firstUser.addColleague(secondUser);
+		thirdUser.addColleague(firstUser);
+
+		flushTestUsers();
+
+		assertThat(repository.countByColleagues(secondUser)).isOne();
+		assertThat(repository.countByColleaguesContaining(secondUser)).isOne();
+	}
+
+	@Test // GH-4179
+	void countOnNestedCollectionPropertyWithIs() {
+
+		firstUser.addColleague(secondUser);
+		firstUser.addColleague(thirdUser);
+
+		secondUser.addRole(adminRole);
+
+		flushTestUsers();
+
+		assertThat(repository.countByColleaguesRoles(adminRole)).isOne();
+	}
+
 	@Test // GH-2593
 	void insertStatementModifyingQueryWorks() {
 		flushTestUsers();

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/sample/UserRepository.java

@@ -561,6 +561,15 @@ public interface UserRepository extends JpaRepository<User, Integer>, JpaSpecifi
 	// GH-4179
 	List<User> findByRoles(Role role);
 
+	// GH-4179
+	long countByColleagues(User user);
+
+	// GH-4179
+	long countByColleaguesContaining(User user);
+
+	// GH-4179
+	long countByColleaguesRoles(Role Role);
+
 	// DATAJPA-829
 	List<User> findByRolesContaining(Role role);