Test to confirm that header names are not trimmed

[swankjesse]

This caused the Go folks some grief. It doesn’t impact us as much (clients control which servers they contact), but it’s good to be careful.

https://groups.google.com/forum/m/#!topic/golang-announce/cszieYyuL9Q

[yschimke]

Seems awkward

https://github.com/1184893257/okhttp/blob/master/okhttp-tests/src/test/java/com/squareup/okhttp/internal/http/HeadersTest.java#L136

  @Test public void ofTrims() {
    Headers headers = Headers.of("\t User-Agent \n", " \r OkHttp ");
    assertEquals("User-Agent", headers.name(0));
    assertEquals("OkHttp", headers.value(0));
  }

https://github.com/1184893257/okhttp/blob/master/okhttp-tests/src/test/java/com/squareup/okhttp/internal/http/HeadersTest.java#L262

  @Test public void ofMapTrimsKey() {
    Headers headers = Headers.of(singletonMap(" User-Agent ", "OkHttp"));
    assertThat(headers.name(0)).isEqualTo("User-Agent");
  }

[yschimke]

@swankjesse Are you happy that we change the behaviour and tests here? Fix is simple if so, and we just publicise it in our release.

[swankjesse]

Unclear what action we should take. Note that there’s another potential attack on response headers.