fs: refactor to avoid unsafe array iteration

[aduh95]

Checklist

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

[aduh95]

Benchmark CI: https://ci.nodejs.org/view/Node.js%20benchmark/job/benchmark-node-micro-benchmarks/850/ (queued, will 404 until it starts)

[aduh95]

Benchmark didn't show any significant regression except maybe one:

 fs/bench-stat-promise.js statType='fstat' n=200000                                                    **     -5.18 %       ±3.33%  ±4.43%  ±5.76%

If no one objects, I'd say that's good enough.

                                                                                               confidence improvement accuracy (*)    (**)   (***)
 fs/bench-mkdirp.js n=10000                                                                                   -0.78 %       ±3.46%  ±4.61%  ±6.01%
 fs/bench-opendir.js bufferSize=1024 mode='async' dir='lib' n=100                                       *      9.79 %       ±8.13% ±10.85% ±14.19%
 fs/bench-opendir.js bufferSize=1024 mode='async' dir='test/parallel' n=100                                    4.69 %       ±5.73%  ±7.63%  ±9.95%
 fs/bench-opendir.js bufferSize=1024 mode='callback' dir='lib' n=100                                          -2.77 %       ±6.49%  ±8.65% ±11.29%
 fs/bench-opendir.js bufferSize=1024 mode='callback' dir='test/parallel' n=100                                 1.36 %       ±4.16%  ±5.55%  ±7.23%
 fs/bench-opendir.js bufferSize=1024 mode='sync' dir='lib' n=100                                        *     11.60 %      ±10.36% ±13.78% ±17.94%
 fs/bench-opendir.js bufferSize=1024 mode='sync' dir='test/parallel' n=100                                     1.26 %       ±3.16%  ±4.21%  ±5.48%
 fs/bench-opendir.js bufferSize=32 mode='async' dir='lib' n=100                                               -2.26 %       ±5.21%  ±6.93%  ±9.02%
 fs/bench-opendir.js bufferSize=32 mode='async' dir='test/parallel' n=100                                     -1.23 %       ±4.98%  ±6.62%  ±8.62%
 fs/bench-opendir.js bufferSize=32 mode='callback' dir='lib' n=100                                            -0.92 %       ±7.47%  ±9.94% ±12.93%
 fs/bench-opendir.js bufferSize=32 mode='callback' dir='test/parallel' n=100                                   4.00 %       ±6.73%  ±8.97% ±11.71%
 fs/bench-opendir.js bufferSize=32 mode='sync' dir='lib' n=100                                                 6.73 %       ±7.86% ±10.46% ±13.62%
 fs/bench-opendir.js bufferSize=32 mode='sync' dir='test/parallel' n=100                                *      1.73 %       ±1.63%  ±2.17%  ±2.83%
 fs/bench-opendir.js bufferSize=4 mode='async' dir='lib' n=100                                          *     -7.30 %       ±7.05%  ±9.40% ±12.28%
 fs/bench-opendir.js bufferSize=4 mode='async' dir='test/parallel' n=100                                      -0.43 %       ±3.38%  ±4.50%  ±5.86%
 fs/bench-opendir.js bufferSize=4 mode='callback' dir='lib' n=100                                              1.32 %       ±6.82%  ±9.08% ±11.82%
 fs/bench-opendir.js bufferSize=4 mode='callback' dir='test/parallel' n=100                                    1.87 %       ±3.87%  ±5.17%  ±6.75%
 fs/bench-opendir.js bufferSize=4 mode='sync' dir='lib' n=100                                                 -1.21 %       ±7.08%  ±9.43% ±12.30%
 fs/bench-opendir.js bufferSize=4 mode='sync' dir='test/parallel' n=100                                 *      1.61 %       ±1.32%  ±1.76%  ±2.30%
 fs/bench-readdir.js withFileTypes='false' dir='lib' n=10                                                     -0.09 %       ±4.04%  ±5.37%  ±6.99%
 fs/bench-readdir.js withFileTypes='false' dir='test/parallel' n=10                                           -2.44 %       ±3.07%  ±4.10%  ±5.36%
 fs/bench-readdir.js withFileTypes='true' dir='lib' n=10                                                       0.33 %       ±5.84%  ±7.81% ±10.24%
 fs/bench-readdir.js withFileTypes='true' dir='test/parallel' n=10                                             0.36 %       ±2.27%  ±3.02%  ±3.93%
 fs/bench-readdirSync.js withFileTypes='false' dir='lib' n=10                                                 -2.18 %       ±6.60%  ±8.79% ±11.44%
 fs/bench-readdirSync.js withFileTypes='false' dir='test/parallel' n=10                                        1.67 %      ±10.07% ±13.49% ±17.74%
 fs/bench-readdirSync.js withFileTypes='true' dir='lib' n=10                                                   1.39 %       ±4.25%  ±5.65%  ±7.35%
 fs/bench-readdirSync.js withFileTypes='true' dir='test/parallel' n=10                                        -3.21 %       ±5.95%  ±7.92% ±10.30%
 fs/bench-realpath.js pathType='relative' n=10000                                                              1.97 %       ±4.24%  ±5.65%  ±7.37%
 fs/bench-realpath.js pathType='resolved' n=10000                                                              2.67 %       ±3.92%  ±5.22%  ±6.79%
 fs/bench-realpathSync.js pathType='relative' n=10000                                                          1.31 %       ±2.81%  ±3.74%  ±4.88%
 fs/bench-realpathSync.js pathType='resolved' n=10000                                                         -2.59 %       ±2.63%  ±3.50%  ±4.56%
 fs/bench-stat.js statType='fstat' n=200000                                                                   -0.83 %       ±4.48%  ±5.96%  ±7.76%
 fs/bench-stat.js statType='lstat' n=200000                                                                   -1.70 %       ±3.93%  ±5.23%  ±6.82%
 fs/bench-stat.js statType='stat' n=200000                                                                     0.09 %       ±4.36%  ±5.80%  ±7.55%
 fs/bench-stat-promise.js statType='fstat' n=200000                                                    **     -5.18 %       ±3.33%  ±4.43%  ±5.76%
 fs/bench-stat-promise.js statType='lstat' n=200000                                                           -0.64 %       ±2.82%  ±3.76%  ±4.90%
 fs/bench-stat-promise.js statType='stat' n=200000                                                            -1.64 %       ±2.71%  ±3.60%  ±4.69%
 fs/bench-statSync-failure.js statSyncType='noThrow' n=1000000                                                -0.10 %       ±3.54%  ±4.71%  ±6.13%
 fs/bench-statSync-failure.js statSyncType='throw' n=1000000                                                  -1.34 %       ±1.92%  ±2.56%  ±3.33%
 fs/bench-statSync.js statSyncType='fstatSync' n=1000000                                                       2.14 %       ±2.56%  ±3.41%  ±4.45%
 fs/bench-statSync.js statSyncType='lstatSync' n=1000000                                                       0.33 %       ±1.89%  ±2.52%  ±3.28%
 fs/bench-statSync.js statSyncType='statSync' n=1000000                                                        0.36 %       ±2.18%  ±2.90%  ±3.78%
 fs/readfile.js concurrent=10 len=1024 duration=5                                                              1.06 %       ±6.91%  ±9.19% ±11.97%
 fs/readfile.js concurrent=10 len=16777216 duration=5                                                         -1.03 %       ±4.38%  ±5.83%  ±7.58%
 fs/readfile.js concurrent=1 len=1024 duration=5                                                               0.81 %       ±2.75%  ±3.66%  ±4.76%
 fs/readfile.js concurrent=1 len=16777216 duration=5                                                           1.80 %      ±15.26% ±20.31% ±26.44%
 fs/readfile-partitioned.js concurrent=10 len=1024 dur=5                                                       1.17 %       ±8.31% ±11.06% ±14.39%
 fs/readfile-partitioned.js concurrent=10 len=16777216 dur=5                                                   0.37 %       ±5.36%  ±7.14%  ±9.30%
 fs/readfile-partitioned.js concurrent=1 len=1024 dur=5                                                        4.98 %       ±7.61% ±10.13% ±13.21%
 fs/readfile-partitioned.js concurrent=1 len=16777216 dur=5                                                   -0.14 %       ±3.41%  ±4.53%  ±5.91%
 fs/readFileSync.js n=600000                                                                                   2.55 %       ±6.87%  ±9.14% ±11.91%
 fs/read-stream-throughput.js n=1024 highWaterMark=1024 filesize=1024000 encodingType='asc'                   -0.68 %       ±3.31%  ±4.41%  ±5.74%
 fs/read-stream-throughput.js n=1024 highWaterMark=1024 filesize=1024000 encodingType='buf'                    0.80 %       ±3.21%  ±4.27%  ±5.58%
 fs/read-stream-throughput.js n=1024 highWaterMark=1024 filesize=1024000 encodingType='utf'                   -1.51 %       ±2.12%  ±2.82%  ±3.67%
 fs/read-stream-throughput.js n=1024 highWaterMark=1048576 filesize=1024000 encodingType='asc'                -0.20 %       ±7.27%  ±9.68% ±12.60%
 fs/read-stream-throughput.js n=1024 highWaterMark=1048576 filesize=1024000 encodingType='buf'                 0.40 %      ±13.36% ±17.85% ±23.38%
 fs/read-stream-throughput.js n=1024 highWaterMark=1048576 filesize=1024000 encodingType='utf'                 3.89 %      ±17.63% ±23.46% ±30.54%
 fs/read-stream-throughput.js n=1024 highWaterMark=4096 filesize=1024000 encodingType='asc'                    0.78 %       ±3.08%  ±4.10%  ±5.33%
 fs/read-stream-throughput.js n=1024 highWaterMark=4096 filesize=1024000 encodingType='buf'                   -0.83 %       ±3.57%  ±4.75%  ±6.18%
 fs/read-stream-throughput.js n=1024 highWaterMark=4096 filesize=1024000 encodingType='utf'                   -0.47 %       ±8.42% ±11.21% ±14.59%
 fs/read-stream-throughput.js n=1024 highWaterMark=65535 filesize=1024000 encodingType='asc'                   4.95 %       ±9.17% ±12.20% ±15.89%
 fs/read-stream-throughput.js n=1024 highWaterMark=65535 filesize=1024000 encodingType='buf'                   4.57 %      ±14.26% ±18.98% ±24.72%
 fs/read-stream-throughput.js n=1024 highWaterMark=65535 filesize=1024000 encodingType='utf'                   0.42 %       ±3.99%  ±5.32%  ±6.94%
 fs/write-stream-throughput.js size=1024 encodingType='asc' dur=5                                              1.32 %       ±5.57%  ±7.41%  ±9.65%
 fs/write-stream-throughput.js size=1024 encodingType='buf' dur=5                                             -0.07 %       ±8.90% ±11.84% ±15.41%
 fs/write-stream-throughput.js size=1024 encodingType='utf' dur=5                                              4.33 %       ±6.12%  ±8.14% ±10.60%
 fs/write-stream-throughput.js size=1048576 encodingType='asc' dur=5                                          -0.63 %       ±4.50%  ±5.99%  ±7.80%
 fs/write-stream-throughput.js size=1048576 encodingType='buf' dur=5                                           3.35 %      ±10.59% ±14.10% ±18.35%
 fs/write-stream-throughput.js size=1048576 encodingType='utf' dur=5                                           1.70 %       ±3.27%  ±4.35%  ±5.67%
 fs/write-stream-throughput.js size=2 encodingType='asc' dur=5                                                 0.09 %      ±11.28% ±15.01% ±19.55%
 fs/write-stream-throughput.js size=2 encodingType='buf' dur=5                                                 7.06 %      ±11.23% ±14.95% ±19.46%
 fs/write-stream-throughput.js size=2 encodingType='utf' dur=5                                                -1.31 %      ±11.01% ±14.65% ±19.07%
 fs/write-stream-throughput.js size=65535 encodingType='asc' dur=5                                            -8.08 %      ±12.60% ±16.77% ±21.83%
 fs/write-stream-throughput.js size=65535 encodingType='buf' dur=5                                             0.04 %      ±11.74% ±15.62% ±20.34%
 fs/write-stream-throughput.js size=65535 encodingType='utf' dur=5                                            -1.51 %       ±9.06% ±12.07% ±15.74%

Be aware that when doing many comparisons the risk of a false-positive
result increases. In this case there are 75 comparisons, you can thus
expect the following amount of false-positive results:
  3.75 false positives, when considering a   5% risk acceptance (*, **, ***),
  0.75 false positives, when considering a   1% risk acceptance (**, ***),
  0.07 false positives, when considering a 0.1% risk acceptance (***)

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/35286/

[aduh95]

Landed in 9e1e890