test-gzip now failing when using node 10.1

[gareth-robinson]

Summary

When running the CI tests against node 10.1. a number of the tests cause deprecation warnings, but the test-gzip fails test 'do not try to pipe responses with no body'

{ Error: socket hang up
    at createHangUpError (_http_client.js:313:15)
    at Socket.socketOnEnd (_http_client.js:409:23)
    at Socket.emit (events.js:187:15)
    at endReadableNT (_stream_readable.js:1086:12)
    at process._tickCallback (internal/process/next_tick.js:63:19) code: 'ECONNRESET' }

Simplest Example to Reproduce

As above, just run CI tests against node 10.1

node_modules/.bin/taper tests/test-gzip.js

Possible Solution

The particular failing test in test-gzip creates a test server and then tries getting 105, 204 and 304 responses for it in order to test empty responses (lines 270-295 in test-gzip.js). If I comment out the '105' part of the test it passes.
The reason the 105 test fails appears to be as a result of this issue/fix in node
nodejs/node#9282
nodejs/node#18033
I think as a result of the change, Informational responses leave the response open for another response to be written later - so doing

res.writeHead(105, ...
res.end()

no longer leaves the response in the right state.

Context

Means that any pull request submitted will not get a green build.

[gareth-robinson]

Looks like this is already being looked at, with this commit: 0c5db42 ("Skip status code 105 on Node > v10").
So I'll close this issue once that's merged in!

[simov]

Yep, I just skipped it. There is a change in how 105 status code is handled in Node v10, but I'm not sure why exactly it was throwing an error.

I've read your comment now, thanks for the info.

[gareth-robinson]

I think if you write an informational response using res.writeHead it clears req.res
https://github.com/nodejs/node/blob/master/lib/_http_client.js#L527
but if you then call res.end after that without actually sending a real response, it hits this line
https://github.com/nodejs/node/blob/master/lib/_http_client.js#L420
and emits the hang up error.
So the error message isn't really correct - it wasn't a socket hangup, it was just ending the response without actually sending anything.