"spy"ing is the root cause of a huge memory leak3.3.1RC43.3.1

This particular mocking of a WrappableTreeViewer was the source of a
memory leak preventing java to retrieve 700MB of memory even after the
end of that JUnit test.

Change-Id: I994e6c2e32ef6b267be9d2e465b57dcae3ffffb2

2 files changed, 30 insertions, 36 deletions

diff --git a/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/NavigatableTest.java b/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/NavigatableTest.java
index e443f7003..eeed3cd20 100644
--- a/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/NavigatableTest.java
+++ b/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/NavigatableTest.java
@@ -19,7 +19,6 @@ import static org.junit.Assert.assertTrue;
 import com.google.common.base.Strings;
 
 import org.eclipse.compare.INavigatable;
-import org.eclipse.emf.common.notify.Adapter;
 import org.eclipse.emf.compare.ide.ui.internal.structuremergeviewer.Navigatable;
 import org.eclipse.emf.compare.ide.ui.tests.structuremergeviewer.TestContext.TestNavigatable;
 import org.eclipse.swt.widgets.Display;
@@ -52,10 +51,7 @@ public class NavigatableTest {
 
 	@After
 	public void after() {
-		Tree swtTree = testContext.getTree();
-		if (swtTree != null) {
-			swtTree.dispose();
-		}
+		testContext.dispose();
 		shell.dispose();
 	}
 
@@ -180,10 +176,11 @@ public class NavigatableTest {
 	}
 
 	private void assertSelectedItemIndex(int index) {
-		Adapter data = ((Adapter)testContext.getTree().getItem(index).getData());
-		Object[] selection = testContext.getCurrentSelection();
-		assertEquals(1, selection.length);
-		assertTrue(data == selection[0]);
+		Object data = testContext.getTree().getItem(index).getData();
+		assertNotNull(data);
+		Object[] currentSelection = testContext.getCurrentSelection();
+		assertEquals(1, currentSelection.length);
+		assertTrue(data == currentSelection[0]);
 	}
 
 	private void assertAllNextItems(TestNavigatable navigatable, TestContext context) {
diff --git a/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/TestContext.java b/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/TestContext.java
index 34e410d08..961edeeb9 100644
--- a/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/TestContext.java
+++ b/plugins/org.eclipse.emf.compare.ide.ui.tests/src/org/eclipse/emf/compare/ide/ui/tests/structuremergeviewer/TestContext.java
@@ -11,10 +11,7 @@
  *******************************************************************************/
 package org.eclipse.emf.compare.ide.ui.tests.structuremergeviewer;
 
-import static org.mockito.Matchers.any;
-import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.when;
 
 import java.util.HashMap;
@@ -28,14 +25,13 @@ import org.eclipse.emf.compare.ide.ui.internal.structuremergeviewer.EMFCompareSt
 import org.eclipse.emf.compare.ide.ui.internal.structuremergeviewer.Navigatable;
 import org.eclipse.emf.compare.ide.ui.internal.structuremergeviewer.WrappableTreeViewer;
 import org.eclipse.emf.edit.tree.TreeNode;
-import org.eclipse.jface.viewers.ISelection;
-import org.eclipse.jface.viewers.StructuredSelection;
+import org.eclipse.jface.viewers.IOpenListener;
+import org.eclipse.jface.viewers.IStructuredSelection;
+import org.eclipse.jface.viewers.OpenEvent;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.swt.widgets.Tree;
 import org.eclipse.swt.widgets.TreeItem;
-import org.mockito.invocation.InvocationOnMock;
-import org.mockito.stubbing.Answer;
 
 /**
  * Utils class used for creating the {@link Tree} and the {@link WrappableTreeViewer}.
@@ -51,7 +47,7 @@ final class TestContext {
 
 	private Tree swtTree;
 
-	private Map<Integer, TreeItem> itemRetreiver;
+	private Map<Integer, TreeItem> itemRetriever;
 
 	private WrappableTreeViewer viewer;
 
@@ -62,7 +58,7 @@ final class TestContext {
 	public TestContext(Shell shell) {
 		super();
 		currentShell = shell;
-		this.itemRetreiver = new HashMap<Integer, TreeItem>();
+		this.itemRetriever = new HashMap<Integer, TreeItem>();
 	}
 
 	private Integer increment() {
@@ -74,13 +70,21 @@ final class TestContext {
 	}
 
 	public TreeItem getItem(int id) {
-		return itemRetreiver.get(Integer.valueOf(id));
+		return itemRetriever.get(Integer.valueOf(id));
 	}
 
 	public int getNumberOfNodes() {
 		return counter - 1;
 	}
 
+	public void dispose() {
+		if (swtTree != null) {
+			swtTree.dispose();
+			swtTree = null;
+		}
+		itemRetriever.clear();
+	}
+
 	/**
 	 * Builds a {@link Tree} (convenience method for calling {@link #buildTree(int, int, boolean)} with
 	 * useString = <code>true</code>)
@@ -111,30 +115,23 @@ final class TestContext {
 			swtTree = new Tree(currentShell, SWT.NONE);
 			swtTree.setData("root"); //$NON-NLS-1$
 			createSubNodes(swtTree, numberOfChildren, depth, useStrings);
-			viewer = spy(new WrappableTreeViewer(swtTree));
-			doAnswer(selectionChanged()).when(viewer).setSelection(any(ISelection.class));
+			viewer = new WrappableTreeViewer(swtTree);
+			viewer.addOpenListener(new IOpenListener() {
+				public void open(OpenEvent event) {
+					if (event.getSelection() instanceof IStructuredSelection) {
+						currentSelection = ((IStructuredSelection)event.getSelection()).toArray();
+					}
+				}
+			});
 			AdapterFactory adapterFactory = mock(AdapterFactory.class);
 			EMFCompareStructureMergeViewerContentProvider contentProvider = new EMFCompareStructureMergeViewerContentProvider(
-					adapterFactory, viewer); // mock(EMFCompareStructureMergeViewerContentProvider.class);
+					adapterFactory, viewer);
 			return new TestNavigatable(viewer, contentProvider);
 		} else {
 			throw new AssertionError("The tree can only be built once"); //$NON-NLS-1$
 		}
 	}
 
-	private Answer<Void> selectionChanged() {
-		return new Answer<Void>() {
-			public Void answer(InvocationOnMock invocation) throws Throwable {
-				ISelection selection = (ISelection)invocation.getArguments()[0];
-				if (selection instanceof StructuredSelection) {
-					currentSelection = ((StructuredSelection)selection).toArray();
-				}
-				invocation.callRealMethod();
-				return null;
-			}
-		};
-	}
-
 	private void createSubNodes(Object parent, int numberOfChild, int depth, boolean useStrings) {
 		if (depth > 0) {
 			for (int childIndex = 0; childIndex < numberOfChild; childIndex++) {
@@ -157,7 +154,7 @@ final class TestContext {
 					when(notifier.getData()).thenReturn(diff);
 					item.setData(adapter);
 				}
-				itemRetreiver.put(increment, item);
+				itemRetriever.put(increment, item);
 				createSubNodes(item, numberOfChild, depth - 1, useStrings);
 			}
 		}