test: set umask for tests

[Trott]

#25213 proposes setting umask in the
Python test runner to avoid spurious test failures when running from a
shell with a restrictive umask. This is a good idea, but will only fix
the issue for tests run with the Python runner. Set it in
common/index.js as well so that it fixes it even when tests are run
directly with a node binary, bypassing the Python test runner.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• commit message follows commit guidelines

[nodejs-github-bot]

@Trott build started: https://ci.nodejs.org/blue/organizations/jenkins/node-test-pull-request-lite-pipeline/detail/node-test-pull-request-lite-pipeline/2070/pipeline

[Trott]

Before:

$ umask 077 && ./node test/parallel/test-fs-mkdir-mode-mask.js 
assert.js:86
  throw new AssertionError(obj);
  ^

AssertionError [ERR_ASSERTION]: Expected values to be strictly equal:

384 !== 420

    at test (/Users/trott/io.js/test/parallel/test-fs-mkdir-mode-mask.js:32:12)
    at Object.<anonymous> (/Users/trott/io.js/test/parallel/test-fs-mkdir-mode-mask.js:44:1)
    at Module._compile (internal/modules/cjs/loader.js:718:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:729:10)
    at Module.load (internal/modules/cjs/loader.js:617:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:560:12)
    at Function.Module._load (internal/modules/cjs/loader.js:552:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:771:12)
    at executeUserCode (internal/bootstrap/node.js:389:15)
    at startExecution (internal/bootstrap/node.js:328:3)
$ 

After:

$ umask 077 && ./node test/parallel/test-fs-mkdir-mode-mask.js 
$ 

[Trott]

CI: https://ci.nodejs.org/job/node-test-pull-request/19820/

[lpinca]

Lot of failures.

[Trott]

Lot of failures.

Yes, I added the WIP label because it needs to account for situations (mostly or entirely worker_threads in our tests) where process.umask() is not available.

[Trott]

Yes, I added the WIP label because it needs to account for situations (mostly or entirely worker_threads in our tests) where process.umask() is not available.

It's probably as simple as checking for existence first and doing nothing if it's not there (and assuming a parent process took care of it) but I want to check carefully to make sure there's nothing that requires anything more than that.

[Trott]

CI: https://ci.nodejs.org/job/node-test-pull-request/20037/

[Trott]

CI: https://ci.nodejs.org/job/node-test-pull-request/20038/

[Trott]

Landed in a53518d