Bug 36625 "Copy Trace" Action in "Failure Trace" View enabled for empty table.
The "Copy Trace" action should probably be hidden or unavailable when there is nothing in the "Failure Trace" view. Currently the user is given the option to copy a trace of nothing to the clipboard.
org.eclipse.jdt.junit/src/org/eclipse/jdt/internal/junit/ui/TestRunnerViewPart.java
public void testTreeEntry(final String treeEntry){
		postSyncRunnable(new Runnable() {
			public void run() {
				if(isDisposed()) 
					return;
				for (Enumeration e= fTestRunViews.elements(); e.hasMoreElements();) {
					ITestRunView v= (ITestRunView) e.nextElement();
					v.newTreeEntry(treeEntry);
				}
			}
		});	
	}
	public void startTestRunListening(IJavaElement type, int port, ILaunch launch) {
		fTestProject= type.getJavaProject();
		fLaunchMode= launch.getLaunchMode();
		aboutToLaunch();
		
		if (fTestRunnerClient != null) {
			stopTest();
		}
		fTestRunnerClient= new RemoteTestRunnerClient();
		
		
		Vector listeners= JUnitPlugin.getDefault().getTestRunListeners();	
		ITestRunListener[] listenerArray= new ITestRunListener[listeners.size()+1];
		listeners.copyInto(listenerArray);
		System.arraycopy(listenerArray, 0, listenerArray, 1, listenerArray.length-1);
		listenerArray[0]= this;
		fTestRunnerClient.startListening(listenerArray, port);