assertThat(source.readUtf8(halfResponseBody.length.toLong())).isEqualTo(halfResponseBody)
      source.close()
      assertFailsWith<IllegalStateException> {
        source.readUtf8()
      }
      assertFailsWith<IOException> {
        response.peekTrailers()
      }
      assertFailsWith<IOException> {
        response.trailers()
      }
    }
  }

  private fun MockResponse.Builder.body(