C#: Add types for pattern expressions. - #22681
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🟡 Changes recommended
The converted-type helper records the unconverted type’s nullability annotation.
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What changed in this PR
Adds extracted types for C# pattern expressions across supported language versions.
Changes:
- Adds converted-type extraction for six pattern kinds.
- Introduces a reusable converted-type helper.
- Adds C# 8, 9, and 11 test coverage.
| File | Description |
|---|---|
csharp/extractor/Semmle.Extraction.CSharp/CodeAnalysisExtensions/SymbolExtensions.cs |
Adds converted-type lookup. |
csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/BinaryPattern.cs |
Types binary patterns. |
csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/ListPattern.cs |
Types list patterns. |
csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/RecursivePattern.cs |
Types recursive patterns. |
csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/RelationalPattern.cs |
Types relational patterns. |
csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/SlicePattern.cs |
Types slice patterns. |
csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/UnaryPattern.cs |
Types unary patterns. |
csharp/ql/test/library-tests/csharp8/patterns.ql |
Queries extracted pattern types. |
csharp/ql/test/library-tests/csharp8/patterns.expected |
Updates C# 8 expected results. |
csharp/ql/test/library-tests/csharp9/patternExprTypes.ql |
Adds C# 9 type query. |
csharp/ql/test/library-tests/csharp9/patternExprTypes.expected |
Adds C# 9 expected results. |
csharp/ql/test/library-tests/csharp11/patternExprTypes.ql |
Adds C# 11 type query. |
csharp/ql/test/library-tests/csharp11/patternExprTypes.expected |
Adds C# 11 expected results. |
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This adds types to most of the pattern expressions. The only exclusions are property pattern- and positional pattern expressions, but they are mostly used as a part of a recursive pattern - which is then either a property- or positional pattern as a child (maybe patterns could have been modelled differently - but that is out of scope for this PR). The "type" is then added to the recursive pattern itself.