@Test
public void testCopyUrlStreams() throws Exception {

    final File testOutDir = new File(testOutBaseDir, "testCopyUrlStreams");
    FileUtils.deleteDirectory(testOutDir);
    testOutDir.mkdirs();
    final File copyMe1 = new File(srcDir, "copyme.txt");
    final File copyMe2 = new File(srcDir, "sub1/copyme.txt");
    final Result<Map<URL, String>> result = OpearPackageMojo.copyUrlStreams(testOutDir,
            Stream.of(copyMe1, copyMe2)
                    .map(Fun.compose1(File::toURI, Fun.uncheck1(URI::toURL)))
                    .collect(Collectors.toList())).teeLogError();
    assertTrue("result is successful: " + result.getError(), result.isSuccess());
    assertEquals("same values",
            Stream.of("copyme.txt", "copyme_1.txt")
                    .collect(Collectors.toSet()),
            new HashSet<>(result.getOrDefault(Collections.emptyMap()).values()));
}