http: ignore multiple abort

[ronag]

All calls expect the first to abort should be a noop. abort event should not be emitted more than once.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

[lpinca]

Does this actually test the change? As far as I can tell 'abort' was emitted only once even before. Can we have a better test?

[ronag]

What do you mean? I call abort() twice and 'abort' is only emitted once...

[lpinca]

Yes, that's my point. it works like this even without the changes proposed here, so it is not clear what this is testing.

[lpinca]

'use strict';

const http = require('http');

const server = http.createServer(function(req, res) {
  res.flushHeaders();
});

server.listen(function() {
  const req = http.get({ port: server.address().port });

  req.on('response', function(res) {
    const dump = res._dump;

    res._dump = function() {
      console.log('dump');
      dump.apply(res, arguments);
    };

    req.abort();
    req.abort();
    req.abort();
    req.abort();
  });

  req.on('abort', function() {
    console.log('abort');
  });
});

'abort' is already emitted only once. The difference is that res._dump() is only called once now. Hope it makes sense.

[ronag]

Makes sense. Updated. Not pretty but I can't see any other way.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/24522/

[Trott]

Does it make sense to make this a separate test rather than modifying the existing test? My concern is that the existing test is such a straightforward one and this kind of makes it less obvious what's going on. (There's no comment explaining why req.abort() is being called twice. But also wouldn't we want a test where it is only called once?)

[ronag]

This is sorted better by #29192