benchmark: fix fs\bench-realpathSync.js

[vsemozhetbyt]

Checklist

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

Affected core subsystem(s)

benchmark, fs

fs\bench-realpathSync.js runs safely only if its cwd is its __dirname. In other cases, it throws ENOENT: no such file or directory. This commit makes it callable from any place (including being a part of the fs suite launched from any directory).

[mscdex]

I've been running that benchmark quite a bit lately and haven't had problems running it outside of the benchmark/fs/ directory, including via benchmark/compare.js. How are you triggering the error exactly?

[vsemozhetbyt]

@mscdex

J:\temp\_git\node-fork\benchmark\fs>bench-realpathSync.js
fs\bench-realpathSync.js type="relative" n=10000: 4,399.895823842575
fs\bench-realpathSync.js type="resolved" n=10000: 4,541.6802584585585

J:\temp>j:\temp\_git\node-fork\benchmark\fs\bench-realpathSync.js
fs.js:960
  binding.lstat(pathModule._makeLong(path), statValues);
          ^

Error: ENOENT: no such file or directory, lstat 'J:\lib'
    at Object.fs.lstatSync (fs.js:960:11)
    at Object.realpathSync (fs.js:1630:21)
    at relativePath (J:\temp\_git\node-fork\benchmark\fs\bench-realpathSync.js:31:8)
    at main (J:\temp\_git\node-fork\benchmark\fs\bench-realpathSync.js:21:5)
    at Benchmark.process.nextTick (J:\temp\_git\node-fork\benchmark\common.js:34:28)
    at _combinedTickCallback (internal/process/next_tick.js:73:7)
    at process._tickCallback (internal/process/next_tick.js:104:9)
    at Module.runMain (module.js:607:11)
    at run (bootstrap_node.js:425:7)
    at startup (bootstrap_node.js:146:9)

[vsemozhetbyt]

Also:

J:\temp>node _git\node-fork\benchmark\compare.js --old node.v8-5.9.exe --new node.v8-5.9.turbo-on.exe --filter bench-realpathSync.js fs > bm.csv
[00:00:01|%   0| 0/1 files |  0/60 runs | 0/2 configs]: fs\bench-realpathSync.jsfs.js:878
  binding.lstat(pathModule._makeLong(path), statValues);
          ^

Error: ENOENT: no such file or directory, lstat 'J:\lib'
    at Object.fs.lstatSync (fs.js:878:11)
    at Object.realpathSync (fs.js:1548:21)
    at relativePath (J:\temp\_git\node-fork\benchmark\fs\bench-realpathSync.js:31:8)
    at main (J:\temp\_git\node-fork\benchmark\fs\bench-realpathSync.js:21:5)
    at Benchmark.process.nextTick (J:\temp\_git\node-fork\benchmark\common.js:34:28)
    at _combinedTickCallback (internal/process/next_tick.js:73:7)
    at process._tickCallback (internal/process/next_tick.js:104:9)
    at Module.runMain (module.js:607:11)
    at run (bootstrap_node.js:425:7)
    at startup (bootstrap_node.js:146:9)

[vsemozhetbyt]

Linter CI: https://ci.nodejs.org/job/node-test-linter/7706/

[vsemozhetbyt]

@mscdex Is it OK to land this or should I provide more info?

[mscdex]

It's fine by me I guess.

[vsemozhetbyt]

Landed in ab2d49b

[seishun]

Not a big thing, but I'd just like to note for future reference that forward slashes are preferable in paths.

[vsemozhetbyt]

@seishun Thank you. Sorry.

[MylesBorins]

This does not land cleanly in LTS. Please feel free to manually backport. Please also feel free to replace do-not-land if it is being backported

edit: nvm it lands 🎉