new PercentEscaper("-+#abc.!", false);
      fail(msg);
    } catch (IllegalArgumentException expected) {
      assertThat(expected).hasMessageThat().isEqualTo(msg);
    }
  }

  public void testBadArguments_plusforspace() {
    // space can be a safe char if plusForSpace is false
    PercentEscaper unused = new PercentEscaper(" ", false);

    // space cannot be a safe char is plusForSpace is true

      new PercentEscaper("-+#abc.!", false);
      fail(msg);
    } catch (IllegalArgumentException expected) {
      assertThat(expected).hasMessageThat().isEqualTo(msg);
    }
  }

  public void testBadArguments_plusforspace() {
    // space can be a safe char if plusForSpace is false
    PercentEscaper unused = new PercentEscaper(" ", false);

    // space cannot be a safe char is plusForSpace is true