Bug 330553 [Import/Export] Importing a project that exists in workspace location merges the contents
(1) Create a project in the default location (2) Export it to an archive (3) Delete it (but don't choose the option to delete from disk) (4) Make some changes in the <workspace root>/<project> directory (4) Import the archive you exported in step 2 This results in files from both the archive and directory. If the directory already has a file thats available in the archive, then it doesn't modify it. Ideally we shouldn't be allowing the import at all.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/wizards/datatransfer/WizardProjectsImportPage.java
this.projectArchiveFile = file;
			this.parent = parent;
			this.level = level;
			setProjectName();
		}
		/**
		 * Set the name of the project based on the projectFile.
		 */
		private void setProjectName() {
			try {
				if (projectArchiveFile != null) {
					InputStream stream = structureProvider
							.getContents(projectArchiveFile);
					
					if (stream == null) {
						if (projectArchiveFile instanceof ZipEntry) {
							IPath path = new Path(
									((ZipEntry) projectArchiveFile).getName());
							projectName = path.segment(path.segmentCount() - 2);
						} else if (projectArchiveFile instanceof TarEntry) {
							IPath path = new Path(
									((TarEntry) projectArchiveFile).getName());
							projectName = path.segment(path.segmentCount() - 2);
						}
					} else {
						description = IDEWorkbenchPlugin.getPluginWorkspace()
								.loadProjectDescription(stream);
						stream.close();
						projectName = description.getName();
					}