fix: preserve same-transaction changes when moving a sub-bucket - #1239
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fix: preserve same-transaction changes when moving a sub-bucket#1239Spider2298 wants to merge 1 commit into
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A sub-bucket modified in the same transaction as a MoveBucket had its pending changes dropped, because the materialized bucket was removed from the source cache and never spilled under the destination. Signed-off-by: Michael Ellis <anz5michael@gmail.com>
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MoveBucketsilently drops changes made to a sub-bucket in the same transaction as the move. In the worst case, a bucket that is created, populated, and moved within a single transaction ends up empty after commit, with no error.The moved sub-bucket is removed from the source bucket's in-memory cache, and its current on-disk header is written under the destination. But a sub-bucket materialized earlier in the transaction keeps its pending changes in that cached in-memory bucket, which is only spilled at commit while walking the parent's cache. Dropped from the source and never added to the destination, it is never spilled, so the changes are lost. The existing tests don't catch this because they always populate the source in one transaction and move it in another.
This carries the materialized sub-bucket over to the destination's cache so its pending changes (including those of nested sub-buckets) are spilled correctly. Adds
TestTx_MoveBucket_PendingChangescovering a modify-then-move and a create-populate-move within a single transaction; both fail without the fix.Authored with help from Claude.