Ensure classpath roots are directories

junit-engine-api/src/main/java/org/junit/gen5/engine/discovery/ClasspathSelector.java

@@ -10,12 +10,12 @@
 
 package org.junit.gen5.engine.discovery;
 
+import static java.util.stream.Collectors.toList;
 import static org.junit.gen5.commons.meta.API.Usage.Experimental;
 
 import java.io.File;
 import java.util.List;
 import java.util.Set;
-import java.util.stream.Collectors;
 
 import org.junit.gen5.commons.meta.API;
 import org.junit.gen5.commons.util.Preconditions;
@@ -33,20 +33,21 @@
 public class ClasspathSelector implements DiscoverySelector {
 
 	/**
-	 * Create a list of {@code ClasspathSelectors} for the supplied {@code paths}.
+	 * Create a list of {@code ClasspathSelectors} for the supplied {@code directories}.
 	 *
-	 * @param paths the paths to classpath roots in the filesystem; never {@code null}
-	 * @return a list of selectors for the supplied paths; paths which
-	 * do not exist in the filesystem will be filtered out
+	 * @param directories set of directories in the filesystem that represent classpath roots;
+	 * never {@code null}
+	 * @return a list of selectors for the supplied directories; directories which
+	 * do not physically exist in the filesystem will be filtered out
 	 */
-	public static List<DiscoverySelector> selectClasspathRoots(Set<File> paths) {
-		Preconditions.notNull(paths, "paths must not be null");
+	public static List<DiscoverySelector> selectClasspathRoots(Set<File> directories) {
+		Preconditions.notNull(directories, "directories must not be null");
 
 		// @formatter:off
-		return paths.stream()
-				.filter(File::exists)
+		return directories.stream()
+				.filter(File::isDirectory)
 				.map(ClasspathSelector::new)
-				.collect(Collectors.toList());
+				.collect(toList());
 		// @formatter:on
 	}
 
@@ -57,7 +58,7 @@ private ClasspathSelector(File classpathRoot) {
 	}
 
 	/**
-	 * Get the selected classpath root.
+	 * Get the selected classpath root directory.
 	 */
 	public File getClasspathRoot() {
 		return this.classpathRoot;

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

@@ -10,11 +10,13 @@
 
 package org.junit.gen5.engine.junit5.discovery;
 
+import static java.util.Collections.singleton;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.gen5.api.Assertions.assertEquals;
 import static org.junit.gen5.api.Assertions.assertSame;
 import static org.junit.gen5.api.Assertions.assertTrue;
 import static org.junit.gen5.api.Assertions.expectThrows;
+import static org.junit.gen5.engine.discovery.ClasspathSelector.selectClasspathRoots;
 import static org.junit.gen5.engine.junit5.discovery.JUnit5UniqueIdBuilder.engineId;
 import static org.junit.gen5.engine.junit5.discovery.JUnit5UniqueIdBuilder.uniqueIdForClass;
 import static org.junit.gen5.engine.junit5.discovery.JUnit5UniqueIdBuilder.uniqueIdForMethod;
@@ -24,7 +26,6 @@
 import java.io.File;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -40,7 +41,6 @@
 import org.junit.gen5.engine.TestDescriptor;
 import org.junit.gen5.engine.UniqueId;
 import org.junit.gen5.engine.discovery.ClassSelector;
-import org.junit.gen5.engine.discovery.ClasspathSelector;
 import org.junit.gen5.engine.discovery.MethodSelector;
 import org.junit.gen5.engine.discovery.PackageSelector;
 import org.junit.gen5.engine.discovery.UniqueIdSelector;
@@ -53,7 +53,7 @@
 public class DiscoverySelectorResolverTests {
 
 	private final JUnit5EngineDescriptor engineDescriptor = new JUnit5EngineDescriptor(engineId());
-	private DiscoverySelectorResolver resolver = new DiscoverySelectorResolver();
+	private final DiscoverySelectorResolver resolver = new DiscoverySelectorResolver();
 
 	@Test
 	public void singleClassResolution() {
@@ -366,9 +366,9 @@ public void classpathResolution() {
 		File classpath = new File(
 			DiscoverySelectorResolverTests.class.getProtectionDomain().getCodeSource().getLocation().getPath());
 
-		List<DiscoverySelector> selector = ClasspathSelector.selectClasspathRoots(Collections.singleton(classpath));
+		List<DiscoverySelector> selectors = selectClasspathRoots(singleton(classpath));
 
-		resolver.resolveSelectors(request().selectors(selector).build(), engineDescriptor);
+		resolver.resolveSelectors(request().selectors(selectors).build(), engineDescriptor);
 
 		assertTrue(engineDescriptor.allDescendants().size() > 500, "Too few test descriptors in classpath");
 

junit-tests/src/test/java/org/junit/gen5/launcher/main/TestDiscoveryRequestBuilderTests.java

@@ -10,12 +10,14 @@
 
 package org.junit.gen5.launcher.main;
 
+import static java.util.Collections.singleton;
 import static java.util.stream.Collectors.toList;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.gen5.api.Assertions.assertEquals;
 import static org.junit.gen5.api.Assertions.expectThrows;
 import static org.junit.gen5.engine.FilterResult.excluded;
 import static org.junit.gen5.engine.discovery.ClassSelector.selectClass;
+import static org.junit.gen5.engine.discovery.ClasspathSelector.selectClasspathRoots;
 import static org.junit.gen5.engine.discovery.MethodSelector.selectMethod;
 import static org.junit.gen5.engine.discovery.PackageSelector.selectPackage;
 import static org.junit.gen5.engine.discovery.UniqueIdSelector.selectUniqueId;
@@ -24,7 +26,6 @@
 
 import java.io.File;
 import java.lang.reflect.Method;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 
@@ -128,14 +129,11 @@ public void unavailableFoldersAreNotStoredInDiscoveryRequest() throws Exception
 			// @formatter:off
 			TestDiscoveryRequest discoveryRequest = request()
 					.selectors(
-							ClasspathSelector.selectClasspathRoots(Collections.singleton(new File("/some/local/path")))
+							selectClasspathRoots(singleton(new File("/some/local/path")))
 					).build();
 			// @formatter:on
 
-			List<String> folders = discoveryRequest.getSelectorsByType(ClasspathSelector.class).stream().map(
-				ClasspathSelector::getClasspathRoot).map(File::getAbsolutePath).collect(toList());
-
-			assertThat(folders).isEmpty();
+			assertThat(discoveryRequest.getSelectorsByType(ClasspathSelector.class).size()).isEqualTo(0);
 		}
 
 		@Test
@@ -145,7 +143,7 @@ public void availableFoldersAreStoredInDiscoveryRequest() throws Exception {
 				// @formatter:off
 				TestDiscoveryRequest discoveryRequest = request()
 						.selectors(
-								ClasspathSelector.selectClasspathRoots(Collections.singleton(temporaryFolder))
+								selectClasspathRoots(singleton(temporaryFolder))
 						).build();
 				// @formatter:on