Support rules of type ExternalResource

add tests for the initial rule support.

#433

junit-jupiter-engine/src/test/java/org/junit/jupiter/engine/vintage/rulesupport/ExternalResourceLegacySupportTests.java

@@ -0,0 +1,41 @@
+/*
+ * 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.jupiter.engine.vintage.rulesupport;
+
+import java.io.File;
+import java.io.IOException;
+
+import org.junit.Rule;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.rules.TemporaryFolder;
+
+@ExtendWith(ExternalResourceLegacySupport.class)
+public class ExternalResourceLegacySupportTests {
+
+	private File file;
+
+	@Rule
+	public TemporaryFolder folder = new TemporaryFolder();
+
+	@BeforeEach
+	void setup() throws IOException {
+		this.file = folder.newFile("temp.txt");
+	}
+
+	@Test
+	void checkTemporaryFolder() {
+		System.out.println("file of TemporaryFolder: " + this.file);
+		assert file.canRead();
+	}
+
+}

junit-jupiter-engine/src/test/java/org/junit/jupiter/engine/vintage/rulesupport/ExternalResourceWithoutAdapterTests.java

@@ -0,0 +1,39 @@
+/*
+ * 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.jupiter.engine.vintage.rulesupport;
+
+import org.junit.Rule;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.rules.TemporaryFolder;
+
+public class ExternalResourceWithoutAdapterTests {
+
+	@Rule
+	public TemporaryFolder folder = new TemporaryFolder();
+
+	@BeforeEach
+	void setup() {
+		try {
+			folder.newFile("temp.txt");
+		}
+		catch (Exception exception) {
+			System.out.println("exception = " + exception.getMessage());
+			assert exception.getMessage().equals("the temporary folder has not yet been created");
+		}
+	}
+
+	@Test
+	void checkTemporaryFolder() {
+		// only needed to invoke testing at all
+	}
+
+}