[ThomasK33]

Why

TestLsTreePageCursorWhenTheWalksGitFails/silent_end failed in #764's merge-group run (actions run 42416712375, job test):

tree_resume_fail_test.go:70: resumeTreePage = write |1: broken pipe: the stand-in does not fail the walk as intended

#764 does not touch internal/gitread. The test's stand-in git exits 0 on cat-file --batch without reading its input. A cat-file child that ends before it answers must make the walk decline (errDeclined), so the page falls back to the stream. The walk did that only when its first request reached the pipe before the child was reaped. Then it read the end of the output, and readErr declined. When the request came later, the write failed with EPIPE, and treeSource.request returned that error instead of declining.

The page was the same in both cases: leftToStream sends a walk's git error to the stream too. Only the walk's own outcome changed with timing, and the test checks that outcome.

What changes

treeSource.request declines when the write fails and git ended cleanly. A git that failed (an exit status, a crash, a heap cap) still gives its own error, as before.

Verification

The race needs the walk's write to land after the child has been reaped. Plain runs did not hit it: 0 failures in 200 runs, and 0 in 240 runs with the test process stopped 80% of the time (SIGSTOP 20 ms, SIGCONT 5 ms). So I widened the window: an overlay (not in this PR) sleeps 500 ms before each request write. With the same overlay and N on both sides:

== main (every walk write 500 ms late), N=10
     10 tree_resume_fail_test.go:70: resumeTreePage = write |1: broken pipe: the stand-in does not fail the walk as intended
== fix (every walk write 500 ms late), N=10
      PASS

With the fix and the overlay, the other stand-ins (heap cap, exit, crash) still give git's error, 3 of 3 runs each.

TestTreeSourceRequestAfterGitEnded makes the late write certain without the overlay. It waits for the stand-in to end before it sends the request. Against main:

tree_resume_fail_test.go:106: request after git ended = write |1: broken pipe

The fixed test passes, and so does an exit-status stand-in, which keeps git's error.

Lanes on this head, all with -race: internal/gitlimit, internal/gitread, internal/api and cmd/openstorage pass on PostgreSQL and S3-WAL (-tags=openstorage_viewcheck) and on SQLite. Build, vet, golangci-lint (0 issues), the doc-link check, both --fingerprints-only checks and the gitread cross-compiles (linux and darwin, amd64 and arm64) pass. No file that the verify-lane-schedule or verify-orphan-sweep fingerprints cover changes.

Size

35 changed lines: 6 of production Go and 29 of tests.

---

Generated with xum • Model: anthropic:claude-opus-5-5 • Thinking: xhigh

[ThomasK33]

@codex review

[ThomasK33]

@codex security review

[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-08T00:05:15.210424Z	601445f	Manual request
🔒 Security Review	✅ Completed 2026-11-08T00:08:01.165251Z	601445f	Manual request

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Codex Review: Didn't find any major issues. Hooray!

Reviewed commit: 601445f03f

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🛡️ Codex Security Review

Security review completed. No security issues were found in this pull request.

Reviewed commit: 601445f03f

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