override fun parse(string: String): MediaType = string.toMediaType()

  override fun assertInvalid(
    string: String,
    exceptionMessage: String?,
  ) {
    val e =
      assertFailsWith<IllegalArgumentException> {
        parse(string)
      }
    assertEquals(exceptionMessage, e.message)
  }

    return url.toHttpUrl()
  }

  protected open fun assertInvalid(
    string: String,
    exceptionMessage: String?,
  ) {
    try {
      val result = string.toHttpUrl()
      if (exceptionMessage != null) {
        fail("Expected failure with $exceptionMessage but got $result")
      } else {
        fail("Expected failure but got $result")
      }
    } catch (iae: IllegalArgumentException) {

  protected open fun parse(string: String): MediaType = string.toMediaTypeOrNull()!!

  protected open fun assertInvalid(
    string: String,
    exceptionMessage: String?,
  ) {
    assertNull(string.toMediaTypeOrNull(), exceptionMessage)
  }

  @Test fun testParse() {
    val mediaType = parse("text/plain;boundary=foo;charset=utf-8")
    assertEquals("text", mediaType.type)