filtered.put("a", 1);
    filtered.put("b", 2);
    assertEquals(ImmutableMap.of("a", 1, "b", 2), filtered);

    assertThrows(IllegalArgumentException.class, () -> filtered.put("yyy", 3));
  }

  public void testFilteredKeysIllegalPutAll() {
    Map<String, Integer> unfiltered = createUnfiltered();
    Map<String, Integer> filtered = Maps.filterKeys(unfiltered, NOT_LENGTH_3);
    filtered.put("a", 1);

        Settings s = Settings.newInstance();

        s = s.withLocalRepository("xxx");
        assertEquals("xxx", s.getLocalRepository());

        s = s.withLocalRepository("yyy");
        assertEquals("yyy", s.getLocalRepository());

        s = s.withLocalRepository(null);
        assertNull(s.getLocalRepository());
    }

attempt to auto-detect suitable values. Run it as

	go run detect.go

which will output something similar to

	export GOIOS_DEV_ID="iPhone Developer: xxx@yyy.zzz (XXXXXXXX)"
	export GOIOS_APP_ID=YYYYYYYY.some.bundle.id
	export GOIOS_TEAM_ID=ZZZZZZZZ

If you have multiple devices connected, specify the device UDID with the GOIOS_DEVICE_ID

    filtered.put("a", 1);
    filtered.put("b", 2);
    assertEquals(ImmutableMap.of("a", 1, "b", 2), filtered);

    assertThrows(IllegalArgumentException.class, () -> filtered.put("yyy", 3));
  }

  public void testFilteredKeysIllegalPutAll() {
    Map<String, Integer> unfiltered = createUnfiltered();
    Map<String, Integer> filtered = Maps.filterKeys(unfiltered, NOT_LENGTH_3);
    filtered.put("a", 1);