repeat_row: Add comments around snapshot_latest, documenting the set invariant#36191
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ggevay wants to merge 1 commit intoMaterializeInc:mainfrom
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repeat_row: Add comments around snapshot_latest, documenting the set invariant#36191ggevay wants to merge 1 commit intoMaterializeInc:mainfrom
repeat_row: Add comments around snapshot_latest, documenting the set invariant#36191ggevay wants to merge 1 commit intoMaterializeInc:mainfrom
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ggevay
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Apr 21, 2026
| let as_of = f.step_back().unwrap(); | ||
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| let snapshot = self.snapshot(id, as_of, &self.txns_read).await.unwrap(); | ||
| let snapshot = self.snapshot(id, as_of, &self.txns_read).await?; |
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Not so important for the main point of the PR, but I did it because why unwrap when you can just ?-propagate the same error?
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This is another PR in the
repeat_rowworkstream. I just wanted to make sure thatrepeat_rowwith a negative count can't possibly make theassert_eq!(diff, 1, "snapshot doesn't accumulate to set");insnapshot_latestfire. This seems to be the case, since this is reading a collection that is not a user-collection, so data fromrepeat_rowcan't reach it. (In fact, the set invariant is a much stronger invariant.)This PR just adds code comments documenting the set invariant, and why it holds at the only caller of
snapshot_latest.Resolves SQL-171.