C++: Add missing parent scope cases

[jketema]

This is mostly used to detect the shadowing of variable declarations.

DCA shows no changes. This does break some coding standards tests. I'll update the test results there after this is merged, and open an issue that informs the coding standards people of this. I briefly looked at fixing the query, but (a) it's not clearly documented what the query should do, and (b) this requires digging through about 400 lines of query code, which I find very hard to follow.

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[geoffw0]

It feels like the parent of e should be something associated with the catch block on line 11, rather than the entire function. I can see that this wouldn't fit the current definition of what getParentScope can return. And what you have is probably good enough for what getParentScope is used for.

[jketema]

Yeah, agreed. I struggled a bit with that one initially. What I do now seems to be most in line with all the other cases that are there, and what we want when looking for shadowing.

[geoffw0]

I briefly looked at fixing the query, but (a) it's not clearly documented what the query should do, and (b) this requires digging through about 400 lines of query code, which I find very hard to follow.

Which query is this?

[jketema]

This query: https://github.com/github/codeql-coding-standards/blob/b476450bfb3bf1801c96159580ec66a577ead214/cpp/common/src/codingstandards/cpp/rules/identifierhidden/IdentifierHidden.qll and the associated Scope library: https://github.com/github/codeql-coding-standards/blob/b476450bfb3bf1801c96159580ec66a577ead214/cpp/common/src/codingstandards/cpp/Scope.qll

[geoffw0]

Yep, discussing the intent with one of the authors might help to untangle what's going on there.

[jketema]

I've reported the issue on the coding standards repo. I assume they'll have a look once they upgrade to CodeQL 2.19.3 or later.