test: Add test for piping large input from stdin

[addaleax]

Pull Request check-list

• Does make -j8 test (UNIX) or vcbuild test nosign (Windows) pass with
  this change (including linting)?
• Is the commit message formatted according to CONTRIBUTING.md?
• If this change fixes a bug (or a performance problem), is a regression
  test (or a benchmark) included? (This is a regression test)

Affected core subsystem(s)

test

Description of change

Check that piping a large chunk of data from process.stdin into process.stdout does not lose any data by verifying that the output has the same size as the input.

This is a regression test for #5927 and fails for the commits in the range [ace1009..89abe86).

[cjihrig]

Just out of curiosity, is there any significance to this number? Will this reproduce the issue on all operating systems?

[cjihrig]

LGTM with a question.

[addaleax]

@cjihrig Answering your questions outside of the diff since more people might ask themselves that:

I think any input size above 65536 bytes works, but when adding an additional listener via .on('data', …) to process.stdin, the test became a little flaky (sometimes up to 5 blocks of 65536 bytes each would “make it through” the child process).

I can only verify that this test works on Linux. But as far as I can tell, the underlying issue depended solely on the relative timing of pause() and resume() calls (and the emission of the corresponding events), so I think there’s a good chance this does also catch the bug on other OSes, too.

[addaleax]

Updated with your suggestion.

[evanlucas]

CI: https://ci.nodejs.org/job/node-test-pull-request/2091/

[mcollina]

LGTM

[bnoordhuis]

LGTM and thanks, landed in 761787b.

[jasnell]

@thealphanerd @nodejs/lts ... while this test may not be entirely applicable to v4 but it may still be worth having.

[Fishrock123]

Should probably go onto lts so we can catch anything similar there

[MylesBorins]

@jasnell +1

[MylesBorins]

Landed in v4.x-staging as 1994ac0 with a slight modification as buffer.alloc does not exist in that release stream