Make WorkspaceSessionTests independent from ResourceTest #903

WorkspaceSessionTests currently inherit from ResourceTest and CoreTest.
In order to remove the JUnit 3 inheritance hierarchy and migrate to
JUnit 4, this change replaces the extension of ResourceTest with a usage
of the WorkspaceTestRule and the extension of JUnit 3's TestCase. Due to
the framework for running session tests relying on the test classes
inheriting from JUnit 3's TestCase, this cannot be replaced yet.

Contributes to
#903

resources/tests/org.eclipse.core.tests.resources/src/org/eclipse/core/tests/internal/resources/WorkspacePreferencesTest.java

@@ -14,6 +14,7 @@
  *******************************************************************************/
 package org.eclipse.core.tests.internal.resources;
 
+import static org.eclipse.core.tests.harness.FileSystemHelper.getRandomLocation;
 import static org.eclipse.core.tests.resources.ResourceTestPluginConstants.PI_RESOURCES_TESTS;
 import static org.eclipse.core.tests.resources.ResourceTestUtil.createRandomString;
 import static org.eclipse.core.tests.resources.ResourceTestUtil.removeFromFileSystem;

resources/tests/org.eclipse.core.tests.resources/src/org/eclipse/core/tests/resources/WorkspaceSessionTest.java

@@ -13,6 +13,9 @@
  *******************************************************************************/
 package org.eclipse.core.tests.resources;
 
+import junit.framework.TestCase;
+import org.junit.Rule;
+
 /**
  * Workspace session tests function as follows:  Each test class looks like a typical JUnit test,
  * except the platform is shutdown and restarted after each test method.  The steps for each
@@ -34,7 +37,11 @@
  *
  * @see org.eclipse.core.tests.session.WorkspaceSessionTestSuite
  */
-public class WorkspaceSessionTest extends ResourceTest {
+public class WorkspaceSessionTest extends TestCase {
+
+	@Rule
+	public WorkspaceTestRule workspaceRule = new WorkspaceTestRule();
+
 	/**
 	 * Constructor for WorkspaceSessionTest.
 	 */
@@ -52,8 +59,14 @@ public WorkspaceSessionTest(String name) {
 		super(name);
 	}
 
+	@Override
+	protected void setUp() throws Exception {
+		workspaceRule.before();
+		workspaceRule.setTestName(getName());
+	}
+
 	/**
-	 * Executes the cleanup functionality in {@link ResourceTest#tearDown()} after
+	 * Executes the cleanup functionality in {@link WorkspaceTestRule#after()} after
 	 * the last of the session of this test class (i.e., the last <code>test*</code>
 	 * method) has finished.
 	 * <p>
@@ -63,16 +76,7 @@ public WorkspaceSessionTest(String name) {
 	 * actual test methods.
 	 */
 	public void test___cleanup() throws Exception {
-		super.tearDown();
-	}
-
-	/**
-	 * Cleanup is done after all sessions of this test class in
-	 * {@link #test___cleanup()}. This method is overwritten to do nothing in order
-	 * to not cleanup between the sessions.
-	 */
-	@Override
-	protected final void tearDown() throws Exception {
+		workspaceRule.after();
 	}
 
 }

resources/tests/org.eclipse.core.tests.resources/src/org/eclipse/core/tests/resources/session/Bug_266907.java

@@ -14,6 +14,7 @@
 package org.eclipse.core.tests.resources.session;
 
 import static org.eclipse.core.resources.ResourcesPlugin.getWorkspace;
+import static org.eclipse.core.tests.harness.FileSystemHelper.getTempDir;
 import static org.eclipse.core.tests.resources.ResourceTestPluginConstants.PI_RESOURCES_TESTS;
 import static org.eclipse.core.tests.resources.ResourceTestUtil.createInputStream;
 import static org.eclipse.core.tests.resources.ResourceTestUtil.createTestMonitor;

resources/tests/org.eclipse.core.tests.resources/src/org/eclipse/core/tests/resources/session/TestBug323833.java

@@ -40,7 +40,7 @@ public void test1() throws Exception {
 			return;
 		}
 
-		IFileStore fileStore = getTempStore().getChild(createUniqueString());
+		IFileStore fileStore = workspaceRule.getTempStore().getChild(createUniqueString());
 		createInFileSystem(fileStore);
 
 		// set EFS.ATTRIBUTE_READ_ONLY which also sets EFS.IMMUTABLE on Mac

resources/tests/org.eclipse.core.tests.resources/src/org/eclipse/core/tests/resources/session/TestCreateLinkedResourceInHiddenProject.java

@@ -13,6 +13,7 @@
  *******************************************************************************/
 package org.eclipse.core.tests.resources.session;
 
+import static org.eclipse.core.tests.harness.FileSystemHelper.getTempDir;
 import static org.eclipse.core.tests.resources.ResourceTestPluginConstants.PI_RESOURCES_TESTS;
 import static org.eclipse.core.tests.resources.ResourceTestUtil.createTestMonitor;
 import static org.eclipse.core.tests.resources.ResourceTestUtil.createUniqueString;

resources/tests/org.eclipse.core.tests.resources/src/org/eclipse/core/tests/resources/session/TestWorkspaceEncodingExistingWorkspace.java

@@ -38,7 +38,7 @@ public static Test suite() {
 		try {
 			Files.createDirectories(projectsTree);
 		} catch (IOException e) {
-			fail("Unable to create directories: " + projectsTree, e);
+			fail("Unable to create directories: " + projectsTree + System.lineSeparator() + e);
 		}
 		return suite;
 	}