Bug 161828 [Undo] - second undo on folder move/copy merge restores old snapshot
Project A folder file1 file2 file3 file4 subfolder file1 file2 file3 file4 Move the "folder" to this existing project: Project B folder file1 file2 file3 file4 file5 file6 subfolder file1 file2 file3 file4 The move operation correctly replaces the content of file1, file2, file3, file4 in the ProjectB folder and the content of file1, file2, file3, file4 in the subfolder. Undo the move. The files return to their original location in ProjectA, and the content of the files in ProjectB have reverted to their content before the move. Redo the move. Everything still fine. Undo the move. Now the files have returned to their original location in ProjectA, but the content of the files in ProjectB still have the content from the ProjectA files.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/undo/WorkspaceUndoUtil.java
* @return a ResourceDescription that can be used to restore the deleted
	 *         resource.
	 * @throws CoreException
	 *             propagates any CoreExceptions thrown from the resources API
	 */
	static ResourceDescription delete(IResource resourceToDelete,
			IProgressMonitor monitor, IAdaptable uiInfo,
			boolean forceOutOfSyncDelete, boolean deleteContent)
			throws CoreException {
		ResourceDescription resourceDescription = ResourceDescription
				.fromResource(resourceToDelete);
		if (resourceToDelete.getType() == IResource.PROJECT) {
			
			monitor
					.setTaskName(UndoMessages.AbstractResourcesOperation_DeleteResourcesProgress);
			IProject project = (IProject) resourceToDelete;
			project.delete(deleteContent, forceOutOfSyncDelete, monitor);
		} else {
			
			monitor.beginTask("", 2); 
			monitor
					.setTaskName(UndoMessages.AbstractResourcesOperation_DeleteResourcesProgress);
			int updateFlags;
			if (forceOutOfSyncDelete) {
				updateFlags = IResource.KEEP_HISTORY | IResource.FORCE;
			} else {
				updateFlags = IResource.KEEP_HISTORY;
			}
			resourceToDelete.delete(updateFlags, new SubProgressMonitor(
					monitor, 1));