dotnet-csharp-source-generators

To create a Roslyn source generator in .NET, you implement the IIncrementalGenerator interface to enable efficient, cache-aware code generation. This approach allows you to automatically generate boilerplate code during compilation.

Incremental source generators in .NET provide a cache-aware approach to code generation, improving build-time performance by only re-executing when necessary. Standard generators run unconditionally, whereas incremental generators optimize the pipeline.

You test a C# source generator using CSharpGeneratorDriver to execute the generator within a test harness. This methodology allows you to verify the generated syntax trees and ensure diagnostic reporting behaves as expected.

Yes, you can use built-in .NET source generators like GeneratedRegex and LoggerMessage for compile-time code optimization. These generators pre-compile logic, which significantly enhances Ahead-of-Time (AOT) compatibility by eliminating runtime reflection.

You report diagnostics from an incremental generator in Roslyn by registering a diagnostic descriptor within the generation pipeline. This allows the compiler to surface custom warnings or errors directly in the IDE based on analyzed syntax.

Roslyn source generators cannot modify existing code and are limited to adding new syntax trees during compilation. They also require strict separation from user project dependencies, meaning you cannot use runtime APIs within the generator itself.