@Test public void addParsing() {

  Headers headers = new Headers.Builder()
      .add("foo: bar")
      .add(" foo: baz") // Name leading whitespace is trimmed.
      .add("foo : bak") // Name trailing whitespace is trimmed.
      .add("ping:  pong  ") // Value whitespace is trimmed.
      .add("kit:kat") // Space after colon is not required.
      .build();
  assertEquals(Arrays.asList("bar", "baz", "bak"), headers.values("foo"));
  assertEquals(Arrays.asList("pong"), headers.values("ping"));
  assertEquals(Arrays.asList("kat"), headers.values("kit"));
}