Shared, Rust: Use HasTypeTreeSig for TypeMention

[paldepind]

In the shared type inference library the TypeMention class really just duplicates the content of the HasTypeTreeSig.

This PR turns TypeMention into a parameter to the module. The parameter uses HasTypeTreeSig which removes the duplication. This also gets rid of TypeMentionTypeTree in the shared library.

Adapting Rust is done in two commits. The first is the minimum necessary changes. Here TypeMentionTypeTree still exists on the Rust side. In a second commit Rust's TypeMention is made to directly implement HasTypeTreeSig by renaming resolveTypeAt to getTypeAt. As far as I recall that rename was discussed previously with some disagreement. So consider the last commit a proposal that we can potentially drop from the PR. Personally I like it as it simplifies things and I don't see much difference between using "get" or "resolve".

[Copilot]

Pull request overview

This PR refactors the shared type inference library to eliminate code duplication by making TypeMention a parameter to the Make2 module that uses the HasTypeTreeSig signature. The Rust implementation is adapted by renaming resolveTypeAt to getTypeAt and resolveType to getType to directly implement the HasTypeTreeSig interface, removing the need for the TypeMentionTypeTree adapter class.

Changes:

• Parameterized InputSig2 in the shared library with HasTypeTreeSig TypeMention, removing duplication
• Renamed resolveTypeAt to getTypeAt and resolveType to getType throughout Rust's type inference implementation
• Removed the TypeMentionTypeTree adapter class from both shared and Rust libraries

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
shared/typeinference/codeql/typeinference/internal/TypeInference.qll	Parameterized InputSig2 with HasTypeTreeSig TypeMention, removed TypeMentionTypeTree adapter, renamed internal helpers from resolveTypeMentionRoot to getTypeMentionRoot, updated documentation
rust/ql/lib/codeql/rust/internal/typeinference/TypeMention.qll	Renamed resolveTypeAt to getTypeAt and resolveType to getType in TypeMention class and all subclasses
rust/ql/lib/codeql/rust/internal/typeinference/TypeInferenceConsistency.qll	Updated call from resolveType() to getType()
rust/ql/lib/codeql/rust/internal/typeinference/TypeInference.qll	Updated module instantiation to use Make2<TypeMention, Input2>, updated all call sites to use getTypeAt
rust/ql/lib/codeql/rust/internal/typeinference/FunctionType.qll	Updated calls from resolveTypeAt to getTypeAt
rust/ql/lib/codeql/rust/internal/typeinference/FunctionOverloading.qll	Updated calls from resolveTypeAt to getTypeAt and resolveType to getType
rust/ql/lib/codeql/rust/internal/typeinference/DerefChain.qll	Updated call from resolveTypeAt to getTypeAt
rust/ql/lib/codeql/rust/internal/typeinference/BlanketImplementation.qll	Updated calls from resolveType to getType and resolveTypeAt to getTypeAt
rust/ql/lib/codeql/rust/dataflow/internal/ModelsAsData.qll	Updated calls from resolveType to getType

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[hvitved]

Nice refactor!

[paldepind]

DCA shows nothing as expected.