Change TestFactoryTestDescriptor implementation

- Override isTest(): It is not a test but a test container
- Override hasTests(): It does not have children known at discovery
  time, but should not get pruned by launcher
- In order for PostDiscoveryFilters to be applied Root#isExcluded was
  changed to check static TestDescriptors without children instead of
  only TestDescriptors that return true for isTest()

Fixes #280.

junit-launcher/src/main/java/org/junit/gen5/launcher/main/Root.java

@@ -58,12 +58,12 @@ TestDescriptor getTestDescriptorFor(TestEngine testEngine) {
 
 	void applyPostDiscoveryFilters(TestDiscoveryRequest discoveryRequest) {
 		Filter<TestDescriptor> postDiscoveryFilter = composeFilters(discoveryRequest.getPostDiscoveryFilters());
-		TestDescriptor.Visitor removeExcludedTests = descriptor -> {
-			if (isExcludedTest(descriptor, postDiscoveryFilter)) {
+		TestDescriptor.Visitor removeExcludedTestDescriptors = descriptor -> {
+			if (isExcluded(descriptor, postDiscoveryFilter)) {
 				descriptor.removeFromHierarchy();
 			}
 		};
-		acceptInAllTestEngines(removeExcludedTests);
+		acceptInAllTestEngines(removeExcludedTestDescriptors);
 	}
 
 	/**
@@ -78,8 +78,8 @@ void prune() {
 		pruneEmptyTestEngines();
 	}
 
-	private boolean isExcludedTest(TestDescriptor descriptor, Filter<TestDescriptor> postDiscoveryFilter) {
-		return descriptor.isTest() && postDiscoveryFilter.apply(descriptor).excluded();
+	private boolean isExcluded(TestDescriptor descriptor, Filter<TestDescriptor> postDiscoveryFilter) {
+		return descriptor.getChildren().isEmpty() && postDiscoveryFilter.apply(descriptor).excluded();
 	}
 
 	private void acceptInAllTestEngines(TestDescriptor.Visitor visitor) {

junit-tests/src/test/java/org/junit/gen5/engine/junit5/DynamicTestGenerationTests.java

@@ -93,12 +93,11 @@ void dynamicTestsAreExecutedFromCollection() {
 
 		ExecutionEventRecorder eventRecorder = executeTests(request);
 
-		// @TestFactory methods are counted as both container and test
 		assertAll( //
 			() -> assertEquals(3, eventRecorder.getContainerStartedCount(), "# container started"),
 			() -> assertEquals(2, eventRecorder.getDynamicTestRegisteredCount(), "# dynamic registered"),
-			() -> assertEquals(3, eventRecorder.getTestStartedCount(), "# tests started"),
-			() -> assertEquals(2, eventRecorder.getTestSuccessfulCount(), "# tests succeeded"),
+			() -> assertEquals(2, eventRecorder.getTestStartedCount(), "# tests started"),
+			() -> assertEquals(1, eventRecorder.getTestSuccessfulCount(), "# tests succeeded"),
 			() -> assertEquals(1, eventRecorder.getTestFailedCount(), "# tests failed"),
 			() -> assertEquals(3, eventRecorder.getContainerFinishedCount(), "# container finished"));
 	}
@@ -110,12 +109,11 @@ void dynamicTestsAreExecutedFromIterator() {
 
 		ExecutionEventRecorder eventRecorder = executeTests(request);
 
-		// @TestFactory methods are counted as both container and test
 		assertAll( //
 			() -> assertEquals(3, eventRecorder.getContainerStartedCount(), "# container started"),
 			() -> assertEquals(2, eventRecorder.getDynamicTestRegisteredCount(), "# dynamic registered"),
-			() -> assertEquals(3, eventRecorder.getTestStartedCount(), "# tests started"),
-			() -> assertEquals(2, eventRecorder.getTestSuccessfulCount(), "# tests succeeded"),
+			() -> assertEquals(2, eventRecorder.getTestStartedCount(), "# tests started"),
+			() -> assertEquals(1, eventRecorder.getTestSuccessfulCount(), "# tests succeeded"),
 			() -> assertEquals(1, eventRecorder.getTestFailedCount(), "# tests failed"),
 			() -> assertEquals(3, eventRecorder.getContainerFinishedCount(), "# container finished"));
 	}
@@ -131,8 +129,8 @@ void dynamicTestsAreExecutedFromIterable() {
 		assertAll( //
 			() -> assertEquals(3, eventRecorder.getContainerStartedCount(), "# container started"),
 			() -> assertEquals(2, eventRecorder.getDynamicTestRegisteredCount(), "# dynamic registered"),
-			() -> assertEquals(3, eventRecorder.getTestStartedCount(), "# tests started"),
-			() -> assertEquals(2, eventRecorder.getTestSuccessfulCount(), "# tests succeeded"),
+			() -> assertEquals(2, eventRecorder.getTestStartedCount(), "# tests started"),
+			() -> assertEquals(1, eventRecorder.getTestSuccessfulCount(), "# tests succeeded"),
 			() -> assertEquals(1, eventRecorder.getTestFailedCount(), "# tests failed"),
 			() -> assertEquals(3, eventRecorder.getContainerFinishedCount(), "# container finished"));
 	}

junit5-engine/src/main/java/org/junit/gen5/engine/junit5/descriptor/TestFactoryTestDescriptor.java

@@ -52,11 +52,21 @@ public TestFactoryTestDescriptor(UniqueId uniqueId, Class<?> testClass, Method t
 		super(uniqueId, testClass, testMethod);
 	}
 
+	@Override
+	public boolean isTest() {
+		return false;
+	}
+
 	@Override
 	public boolean isContainer() {
 		return true;
 	}
 
+	@Override
+	public boolean hasTests() {
+		return true;
+	}
+
 	@Override
 	public boolean isLeaf() {
 		return true;