  @Test
  public void testPosixOwnerOnly() throws IOException {

    Path path = createTestFileWithPosixPermissions(
        user("100"),
        group("200"),
        PosixFilePermission.OWNER_READ);

    Acl acl = FilePermissionSample.mapPosixFilePermissionToCloudSearchAcl(path);
    assertThat(acl.getReaders()).hasSize(1);
    List<String> userPrincipalNames = acl.getReaders().stream()
        .map(principal -> principal.getUserResourceName())
        .collect(Collectors.toList());
    assertThat(userPrincipalNames).contains("identitysources/abcdef12345/users/100");
  }