Python: Move min/maxParameter methods to Function class
#18871
Conversation
These seem generally useful outside of points-to, and so it might be better to add them to the `Function` class instead. I took the liberty of renaming these to say `Arguments` rather than `Parameters`, as this is more in line with the nomenclature that we're using elsewhere. (The internal points-to methods retain the old names.) I'm somewhat ambivalent about the behaviour of `getMaxParameters` on functions with `*varargs`. The hard-coded `INT_MAX` return value is somewhat awkward, but the alternative (to only have the predicate defined when a specific maximum exists) seems like it would potentially cause a lot of headaches.
There was a problem hiding this comment.
PR Overview
This PR moves the min/max parameter methods to the Function class and renames them to use “Arguments” for consistency with the rest of the codebase.
- Moved methods from a points-to context into the Function class.
- Renamed the methods to getMinArguments and getMaxArguments, and updated the corresponding change notes.
Reviewed Changes
| File | Description |
|---|---|
| python/ql/lib/change-notes/2025-02-26-add-get-min-max-parameters-to-function-class.md | Added change notes documenting the new Function class methods |
Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.
Tip: Copilot only keeps its highest confidence comments to reduce noise and keep you focused. Learn more
| @@ -163,6 +163,18 @@ class Function extends Function_, Scope, AstNode { | |||
| ret.getValue() = result.getNode() | |||
| ) | |||
| } | |||
|
|
|||
| /** Gets the minimum number of positional arguments that can be correctly passed to this function. */ | |||
| int getMinArguments() { | |||
There was a problem hiding this comment.
Naming: Should these be getMinPositionalArguments, something like that?
There was a problem hiding this comment.
It's a mouthful (and it suggests the existence of getMinKeywordArguments, which I'm not entirely sure makes sense), but it's probably a good idea to proactively disambiguate things here. At the very least, renaming it to something shorter will be easy to do if we feel like it.
| /** Gets the maximum number of positional arguments that can be correctly passed to this function. */ | ||
| int getMaxArguments() { | ||
| if exists(this.getVararg()) | ||
| then result = 2147483647 // INT_MAX |
There was a problem hiding this comment.
Ooh this is an interesting trap. I suggest at least putting it in the QLDoc, i.e. if the function doesn't take varargs, the result is INT_MAX.
There was a problem hiding this comment.
I think you've got a superfluous negation there (if the function does take varargs, the result is INT_MAX), but I agree this should be documented better.
Perhaps here it is appropriate to define a newtype and force users to deal with the two cases explicitly? |
I thought about it for a bit, and I think for the moment it's fine to just use |
Renames the methods to include the word `Positional`, and adds documentation for the behaviour of `getMaxPositionalArguments` when the function in question has a `*varargs` parameter (and hence no upper limit on the number of arguments).
![github-advanced-security[bot]](https://avatars.githubusercontent.com/in/57789?s=60&v=4){kind=small}
| is_quad_op(name) and result = 4 | ||
| } | ||
|
|
||
| predicate declaredAttributeVar(Class cls, string name, EssaVariable var) { |
Check warning
Code scanning / CodeQL
Dead code Warning
These seem generally useful outside of points-to, and so it might be better to add them to the
Functionclass instead.I took the liberty of renaming these to say
Argumentsrather thanParameters, as this is more in line with the nomenclature that we're using elsewhere. (The internal points-to methods retain the old names.)I'm somewhat ambivalent about the behaviour of
getMaxParameterson functions with*varargs. The hard-codedINT_MAXreturn value is somewhat awkward, but the alternative (to only have the predicate defined when a specific maximum exists) seems like it would potentially cause a lot of headaches.