fix: respect maybe-null attributes#2194
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Pull request overview
This PR fixes nullability handling in Mapperly by making the generator respect [MaybeNull] when determining whether a member can produce/accept nulls, addressing CS8601 scenarios like #2192.
Changes:
- Add a centralized
SymbolAccessor.IsNullable(ISymbol)which treats fields/properties/constructor parameters as nullable when their type is nullable or they have[MaybeNull]. - Update member wrappers (property/field/ctor-parameter members) to use the centralized nullability logic.
- Add regression tests covering
MaybeNullcombinations and document the behavior change for v5.0.
Reviewed changes
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Show a summary per file
| File | Description |
|---|---|
| test/Riok.Mapperly.Tests/Mapping/ObjectPropertyNullableTest.cs | Adds regression tests for [MaybeNull] source/target property combinations. |
| src/Riok.Mapperly/Symbols/Members/PropertyMember.cs | Switches IsNullable to use SymbolAccessor.IsNullable (but introduces an unused using). |
| src/Riok.Mapperly/Symbols/Members/FieldMember.cs | Switches IsNullable to use SymbolAccessor.IsNullable (but introduces an unused using). |
| src/Riok.Mapperly/Symbols/Members/ConstructorParameterMember.cs | Switches IsNullable to use SymbolAccessor.IsNullable. |
| src/Riok.Mapperly/Descriptors/SymbolAccessor.cs | Implements IsNullable(ISymbol) and adds a safe TryHasAttribute(ISymbol) helper. |
| docs/docs/breaking-changes/5-0.md | Notes that [MaybeNull] is now respected for relevant members. |
Comments suppressed due to low confidence (2)
src/Riok.Mapperly/Symbols/Members/PropertyMember.cs:3
using System.Diagnostics.CodeAnalysis;appears to be unused in this file after the changes. Please remove it to avoid unnecessary-using warnings (and potential build failures if warnings are treated as errors).
using System.Diagnostics;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp.Syntax;
src/Riok.Mapperly/Symbols/Members/FieldMember.cs:3
using System.Diagnostics.CodeAnalysis;appears to be unused in this file after the changes. Please remove it to avoid unnecessary-using warnings (and potential build failures if warnings are treated as errors).
using System.Diagnostics;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
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Closes #2192