@Test
public void Should_listFiles_listFilesMatchingGivenFilter()
        throws Exception {

    java.nio.file.Path dirPath = Files.createTempDirectory("directory-with-files-");
    Files.createDirectory(dirPath.resolve("1a"));
    Files.createFile(dirPath.resolve("2a"));
    Files.createFile(dirPath.resolve("b"));
    Collection<IPath> paths = filesystemFacade.listFiles(
            new Path(dirPath),
            path -> path.getPath().endsWith("a"));
    assertNotNull(paths);
    assertEquals(1, paths.size());
    assertEquals(dirPath.resolve("2a").toString(), paths.iterator().next().getPath());
}