ls: properly release parent nodes in DFS

[Alonely0]

Fixes a regression introduced in #11386 (sorry) where DFS nodes did not properly free the recorded inodes of the parent directories. This caused critical errors in some instances of recursive hard links, and made memory usage increase with a combinatorical explosion.

[oech3]

Would you add test?

[Alonely0]

Would you add test?

I'm not even sure of how to build a minimum reproducible example lol, but I'll try. I found this by dumb luck.

[codspeed-hq]

Merging this PR will degrade performance by 5.35%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 6 improved benchmarks
❌ 2 regressed benchmarks
✅ 292 untouched benchmarks
⏩ 46 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Memory	ls_recursive_long_all_deep_tree[(100, 4)]	126.3 KB	107.8 KB	+17.12%
⚡	Memory	ls_recursive_mixed_tree	133 KB	122.5 KB	+8.55%
⚡	Memory	ls_recursive_balanced_tree[(6, 4, 15)]	1,817.8 KB	117.3 KB	×15
⚡	Memory	ls_recursive_deep_tree[(200, 2)]	143.3 KB	106.9 KB	+33.98%
⚡	Memory	ls_recursive_long_all_balanced_tree[(6, 4, 15)]	1,988.5 KB	288 KB	×6.9
⚡	Memory	ls_recursive_long_all_mixed_tree	133.6 KB	123.1 KB	+8.51%
❌	Simulation	ls_recursive_wide_tree[(10000, 1000)]	35.3 ms	36.5 ms	-3.27%
❌	Simulation	ls_recursive_balanced_tree[(6, 4, 15)]	51.8 ms	54.8 ms	-5.35%

---

_{Comparing Alonely0:fix-ls-rec (a2cacf1) with main (e0f0318)}

Footnotes

1. 46 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Alonely0]

It appears this fixes this fully fixes the insane memory consumption introduced by the DFS PR lol.

[Alonely0]

Would you add test?

I've discovered I can't since this relies on hard links of directories, which are not a thing on most filesystems.

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/tail/retry. tests/tail/retry is passing on 'main'. Maybe you have to rebase?
Congrats! The gnu test tests/tail/pipe-f2 is no longer failing!
Congrats! The gnu test tests/tail/tail-n0f is now passing!

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/tail/inotify-dir-recreate (fails in this run but passes in the 'main' branch)
Note: The gnu test tests/basenc/bounded-memory is now being skipped but was previously passing.

[oech3]

Windows has many hardlinks on WinSxS, or you can make hardlink at tests.

[Alonely0]

Pushed a quick fix of a bug I found while writing the test lol

[oech3]

Add WINDIR to spell-checker: ignore

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/cut/bounded-memory (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/date/date-locale-hour (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/pr/bounded-memory (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/tail/follow-name (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/tty/tty-eof (passes in this run but fails in the 'main' branch)
Note: The gnu test tests/cp/link-heap is now being skipped but was previously passing.

[oech3]

thread 'test_ls::test_ls_recursive_hardlink_cycles' (8648) panicked at tests\uutests\src\lib\util.rs:2000:35:
called `Result::unwrap()` on an `Err` value: Custom { kind: Other, error: "wait: Timeout of '30s' reached" }