val part1 = body.part(0)
    part1.body.writeTo(part1Buffer)
    assertThat(part1.headers).isEqualTo(headersOf("Foo", "Bar"))
    assertThat(part1Buffer.readUtf8()).isEqualTo("Baz")
  }

  @Test
  fun nonAsciiFilename() {
    val expected =
      """
      |--AaB03x
      |Content-Disposition: form-data; name="attachment"; filename="resumé.pdf"
      |Content-Type: application/pdf; charset=utf-8
      |