// probably URISyntaxException or IllegalArgumentException
        // fall back to copying URLs to files in the testDir == null block below
      }
    }

    if (testDir == null) {
      // testdata resources aren't file:// urls, so create a directory to store them in and then
      // copy the resources to the filesystem as needed
      testDir = createTempDir();
    }

    return testDir;
  }