Swift: extract types for patterns #14570
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We didn't put stats in any other upgrade scripts, do we need this now?
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I don't think we do, no.
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What does this script do? Is it simple removing all the elements?
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I think delete in the upgrade.properties does this, see https://github.com/github/codeql/blob/main/docs/prepare-db-upgrade.md .
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... but that's what you've done in the downgrade script. Are we just trying to synthesize an empty table here?
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Just synthesizing an empty table right now. Is there a better way to do that?
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I'm not sure you need to. I definitely don't consider myself an expert though.
swift/ql/lib/upgrades/c0db61944f46ba5507f207ec2b1cff77ad0529a1/upgrade.properties
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The motivation for this is for type pruning, where we need to assign a meaningful type for dataflow nodes. Some time ago I talked to Robert about what we should do for the dataflow nodes representing patterns, and we agreed that we could probably assign it some notion of a Top type, but it looks like we might as well grab the real type off the patterns (which is what Robert is extracting here).
Very much agree! |
Co-authored-by: Geoffrey White <40627776+geoffw0@users.noreply.github.com>
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DCA looks clean, only thing left is that question about the upgrade script - @AlexDenisov is there a better way to synthesize an empty table? |
I don't know, and I also don't know why we'd need to synthesize a new table 😅 |
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I think the |
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