1349950 - calling FetchController.abort() while Response body being consumed does not cause AbortError

Status: RESOLVED DUPLICATE of bug 1378342

(Core :: DOM: Core & HTML, enhancement)

Description

[Ben Kelly [:bkelly, not reviewing]]

Consider this test case:

const url = '/';
const controller = new FetchController();
const signal = controller.signal;
const observe = (observer) => {
  observer.addEventListener('statechange', event => {
    console.log('state changed to ' + observer.state);
    if (observer.state === 'responding') {
      controller.abort();
    }
  });
}

fetch(url, {signal, observe}).then(r => r.text()).then(text => console.log(text)).catch(err => {
  if (err.name == 'AbortError') {
    console.log('The request/response was aborted');
  } else {
    console.log('Unexpected error: ' + err.name);
  }
});

This will produce the following console output:

"state changed to responding"
"state changed to aborted"
"state changed to complete"
""

Here we aborted the fetch, but the Response.text() still produced an empty string instead of rejecting with AbortError.  Similarly Response.json() will try to parse the truncated output and reject with SyntaxError.

Comment 1

[Ben Kelly [:bkelly, not reviewing]]

Oh, I was getting the empty string because I was on jsbin.  In devtools console on example.com that logs the entire / html file.  Still, I think it should reject instead.

Comment 2

[ziyunfei]

Attachment: fetch-abort.png

I nearly filed a dupe of this.

Comment 3

[Hsin-Yi Tsai (she/her)[:hsinyi]]

 Tom, is this something at your wheelhouse?

Comment 4

[Tom Tung [:tt, :ttung]]

Start to work on this bug.

Comment 5

[Ben Kelly [:bkelly, not reviewing]]

There was some question at the spec meeting if this behavior is correct or not.  We should figure that out before implementing anything here.

Comment 6

[Tom Tung [:tt, :ttung]]

(In reply to Ben Kelly [not reviewing due to deadline][:bkelly] from comment #5)
> There was some question at the spec meeting if this behavior is correct or
> not.  We should figure that out before implementing anything here.

Got it! Thanks for telling me that!