assertThat(sourceBuffer.size).isEqualTo(0)
    source.close()
    assertThat(relay.isClosed).isTrue()
    assertFile(Relay.PREFIX_CLEAN, 13L, metadata.size, "abcdefghijklm", metadata)
  }

  @Test
  fun multipleSources() {
    val upstream = Buffer()
    upstream.writeUtf8("abcdefghijklm")
    val relay = edit(file, upstream, metadata, 1024)
    val source1 = relay.newSource()!!.buffer()
    val source2 = relay.newSource()!!.buffer()