Recheck current file preimages before direct Git Trees merge - #31478
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woahwhattheheck merged 2 commits intoOct 5, 2026
Merged
woahwhattheheck merged 2 commits into
woahwhattheheck merged 2 commits into
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Problem and change
The direct publishGitHubChange merge path checked target preimages before creating its tree, commit and PR, then merged without rechecking a base that may have moved. The existing merge continuation and Contents publisher already perform this current-base check.
Before the direct expected-head merge, read the current base commit/tree. An unchanged immutable base reuses its completed preimage check. A moved base uses the established baseFileReader and exact previous blob/mode/type comparison for every prepared path; changed targets stop with the existing branch and PR retained. Verified retained-tree bytes are re-bound to the current native parent with separate consumed markers. A mismatching parent stops without accepting stale tree bytes.
The expected PR head remains guarded by the same native merge call. This does not provide an atomic expected-base CAS: the base can move after observation. Existing uncertain-write stopping and no automatic retry are unchanged.
Batching and evidence
The existing Git Trees route already creates one tree/commit for a regular-file batch. The guide documents pinned versus inline UTF-8 behavior and the source-modeled call cost; it preserves source pins and full immutable readbacks. The measured 17-file Razer carrier #31476 used 110 Contents-publisher calls, plus 21 separate full-main reads. It was not republished or benchmarked.
Only these existing paths change:
Removing the 24-line insertion reconstructs the complete source preimage. The entire continuation, contribution, observation and Contents implementations remain byte-identical. The guide change is additive.
Validation is static source reasoning and guarded publication/full-text readback through the existing Contents implementation. The new direct-merge branch is not executed by this publication. No tests, fixtures, native process, workflow, historical packet replay or performance run was performed.
Operation: CONNECTED-GITHUB-ATOMIC-PREMERGE-PREIMAGE-20261005-7CA6.
Exact-path coordination: https://tokenjunkielabs.slack.com/archives/C0BTB4SUCP9/p1791166502773229 .
The adjacent large-directory activity is preserved; its traversal/fallback implementation is unchanged.