testHashCode() {
    try {
      googString.hashCode(/** @type {?} */ (null));
      fail('should throw exception for null');
    } catch (ex) {
      // success
    }
    assertHashcodeEquals(0, '');
    assertHashcodeEquals(101574, 'foo');
    assertHashcodeEquals(1301670364, '\uAAAAfoo');
    assertHashcodeEquals(92567585, googString.repeat('a', 5));
    assertHashcodeEquals(2869595232, googString.repeat('a', 6));
    assertHashcodeEquals(3058106369, googString.repeat('a', 7));
    assertHashcodeEquals(312017024, googString.repeat('a', 8));
    assertHashcodeEquals(2929737728, googString.repeat('a', 1024));
  }
Verify we get random-ish looking values for hash of Strings.