Python: Remove some simple uses of points-to#21350
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Moves the classes/predicates that _actually_ depend on points-to to the `LegacyPointsTo` module, leaving behind a module that contains all of the metrics-related stuff (line counts, nesting depth, etc.) that don't need points-to to be evaluated. Consequently, `Metrics` is now no longer a private import in `python.qll`.
The ones that no longer require points-to no longer import `LegacyPointsTo`. The ones that do use the specific `...MetricsWithPointsTo` classes that are applicable.
Removes the use of points-to for accessing various built-ins from three of the queries. In order for this to work I had to extend the lists of known built-ins slightly.
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Uses a (perhaps) slightly coarser approximation of what modules are imported, but it's probably fine.
This module (which for convenience currently resides inside `DataFlowDispatch`, but this may change later) contains convenience predicates for bridging the gap between the data-flow layer and the old points-to analysis.
Uses the new `DuckTyping` module to handle recognising whether a class is a container or not. Only trivial test changes (one version uses "class", the other "Class"). Note that the ported query has no understanding of built-in classes. At some point we'll likely want to replace `hasUnresolvedBase` (which will hold for any class that extends a built-in) with something that's aware of the built-in classes.
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Same comment as for the preceding commit. We lose one test result due to the fact that we don't know what to do about `for ... in 1` (because `1` is an instance of a built-in). I'm going to defer addressing this until we get some modelling of built-in types.
Only trivial test changes.
Depending on whether other queries depend on this, we may end up moving the exception utility functions to a more central location.
Approximates the behaviour of `Types::isNewStyle` but without depending on points-to
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These could arguably be moved to `Class` itself, but for now I'm choosing to limit the changes to the `DuckTyping` module (until we decide on a proper API).
Only trivial test changes.
Only trivial test changes.
For this one we actually lose a test result. However, this is kind of to be expected since we no longer have the "precise" MRO that the points-to analysis computes. Honestly, I'm on the fence about even keeping this query at all. It seems like it might be superfluous in a world with good Python type checking.
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This one is a bit more involved. Of note is the fact that it at present only uses local flow when determining the origin of some value (whereas the points-to version used global flow). It may be desirable to rewrite this query to use global data-flow, but this should be done with some care (as using "all unhashable objects" as the set of sources is somewhat iffy with respect to performance). For that reason, I'm sticking to mostly local flow (except for well behaved things like types and built-ins).
No test changes.
Only trivial test changes.
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WIP