S1121: False positive for Null-conditional assignment in C# 14

Colin · November 12, 2025, 3:05pm

Hey there.

Agreed! It’s already in the backlog. C#14 support is coming soon.

github.com/SonarSource/sonar-dotnet

NET-2391 Fix S1121 FP: Extract (null-forgiving) assignment from expression

opened 02:05AM - 26 Sep 25 UTC

DaleStan

False Positive

### Description SonarQube should not recommend reverting [IDE0031](https://lear…n.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/ide0031) after the fix is applied to the following code. (using `<LangVersion>preview</LangVersion>`, which will become `<LangVersion>14</LangVersion>` in a couple weeks.) ``` class Foo { Foo? child; public void DoSomething(Foo? other) { if (other != null) // IDE0031: Simplify null check other.child = this; } } ``` The automatic fix for IDE0031 changes this code to the reproducer below. ### Reproducer ``` class Foo { Foo? child; public void DoSomething(Foo? other) { other?.child = this; // Unexpected S1121 } } ``` ### Expected behavior S1121 should not be raised on null-forgiving assignments. ### Product and Version SonarQube 8.26.0.14275 on Visual Studio 17.14.15 and Windows 11 24H2.

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S1121: False positive for Null-conditional assignment in C# 14

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