http: Add coverage for socketOnDrain and updateOngoingData

[mcollina]

Our current test suite does not cover

https://github.com/nodejs/node/blob/master/lib/_http_server.js#L381
https://github.com/nodejs/node/blob/master/lib/_http_server.js#L373

where the outgoingData is greater that the highWaterMark

• Version: master
• Platform: all
• Subsystem: http

[sashaaKr]

Hey, I'm going to work on it

[Leko]

@mcollina It seems to covered in latest coverage report.
https://coverage.nodejs.org/coverage-06e1b0386196f8f8/root/_http_server.js.html

But I cannot find test case about socketOnDrain.
This function is covered indirectly by another function tests.

$ git grep socketOnDrain
lib/_http_server.js:342:  state.onDrain = socketOnDrain.bind(undefined, socket, state);
lib/_http_server.js:377:    return socketOnDrain(socket, state);
lib/_http_server.js:381:function socketOnDrain(socket, state) {

Should we write a test according to socketOnDrain ?

[mcollina]

our test suite does not check when needPause becomes false. We should test all the combinations for the various conditionals in socketOnDrain.

[Leko]

We should test all the combinations for the various conditionals in socketOnDrain.

@mcollina Thank you for the detailed explanation.
I got it. I'll try to write test.

[mcollina]

Fixed in a364e7e.

[Leko]

Thank you for your quick response :D