Fixed scanning of static inner classes, tests included.

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

@@ -259,7 +259,7 @@ public void testPackageResolution() {
 			"org.junit.gen5.engine.junit5.descriptor.subpackage");
 		resolver.resolveElement(specification);
 
-		assertEquals(4, engineDescriptor.allDescendants().size());
+		assertEquals(6, engineDescriptor.allDescendants().size());
 		List<String> uniqueIds = uniqueIds();
 		assertTrue(
 			uniqueIds.contains("ENGINE_ID:org.junit.gen5.engine.junit5.descriptor.subpackage.Class1WithTestCases"));
@@ -269,6 +269,8 @@ public void testPackageResolution() {
 			uniqueIds.contains("ENGINE_ID:org.junit.gen5.engine.junit5.descriptor.subpackage.Class2WithTestCases"));
 		assertTrue(uniqueIds.contains(
 			"ENGINE_ID:org.junit.gen5.engine.junit5.descriptor.subpackage.Class2WithTestCases#test2()"));
+		assertTrue(uniqueIds.contains(
+			"ENGINE_ID:org.junit.gen5.engine.junit5.descriptor.subpackage.ClassWithStaticInnerTestCases$ShouldBeDiscovered#test1()"));
 	}
 
 	@Test

junit-tests/src/test/java/org/junit/gen5/engine/junit5/descriptor/subpackage/ClassWithStaticInnerTestCases.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2015-2016 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v1.0 which
+ * accompanies this distribution and is available at
+ *
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.junit.gen5.engine.junit5.descriptor.subpackage;
+
+import org.junit.gen5.api.Test;
+
+public class ClassWithStaticInnerTestCases {
+
+	static class ShouldBeDiscovered {
+		@Test
+		void test1() {
+
+		}
+	}
+
+	private static class ShouldNotBeDiscovered {
+		@Test
+		void test2() {
+
+		}
+	}
+}

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

@@ -23,7 +23,7 @@
 import org.junit.gen5.engine.TestPlanSpecificationElement;
 import org.junit.gen5.engine.TestPlanSpecificationElementVisitor;
 import org.junit.gen5.engine.junit5.discovery.IsNestedTestClass;
-import org.junit.gen5.engine.junit5.discovery.IsTestClassWithTests;
+import org.junit.gen5.engine.junit5.discovery.IsScannableTestClass;
 import org.junit.gen5.engine.junit5.discovery.IsTestMethod;
 
 /**
@@ -35,7 +35,7 @@ public class SpecificationResolver {
 
 	private final IsNestedTestClass isNestedTestClass = new IsNestedTestClass();
 	private final IsTestMethod isTestMethod = new IsTestMethod();
-	private final IsTestClassWithTests isTestClassWithTests = new IsTestClassWithTests();
+	private final IsScannableTestClass isScannableTestClass = new IsScannableTestClass();
 
 	public SpecificationResolver(JUnit5EngineDescriptor engineDescriptor) {
 		this.engineDescriptor = engineDescriptor;
@@ -61,12 +61,12 @@ public void visitUniqueId(String uniqueId) {
 
 			@Override
 			public void visitPackage(String packageName) {
-				findAllClassesInPackage(packageName, isTestClassWithTests).stream().forEach(this::visitClass);
+				findAllClassesInPackage(packageName, isScannableTestClass).stream().forEach(this::visitClass);
 			}
 
 			@Override
 			public void visitAllTests(File rootDirectory) {
-				ReflectionUtils.findAllClassesInClasspathRoot(rootDirectory, isTestClassWithTests).stream().forEach(
+				ReflectionUtils.findAllClassesInClasspathRoot(rootDirectory, isScannableTestClass).stream().forEach(
 					this::visitClass);
 			}
 		});

junit5-engine/src/main/java/org/junit/gen5/engine/junit5/discovery/IsScannableTestClass.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2015-2016 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v1.0 which
+ * accompanies this distribution and is available at
+ *
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.junit.gen5.engine.junit5.discovery;
+
+import java.util.function.Predicate;
+
+import org.junit.gen5.commons.util.ReflectionUtils;
+
+/**
+ * Test if a class is a JUnit 5 test class which should be included in package and classpath scanning.
+ *
+ * @since 5.0
+ */
+public class IsScannableTestClass implements Predicate<Class<?>> {
+
+	private static final IsTestClassWithTests isTestClassWithTests = new IsTestClassWithTests();
+
+	@Override
+	public boolean test(Class<?> candidate) {
+		//please do not collapse into single return
+		if (ReflectionUtils.isPrivate(candidate))
+			return false;
+		return isTestClassWithTests.test(candidate);
+	}
+
+}