Forwarding Source Generator by Barion

Overview

Provides a .NET Source Generator which aims to simplify the process of forwarding calls to a field or property. This generator works by identifying attributes in the source code and creating forwarding methods based on these attributes. It reduces the amount of boilerplate code you need to write, making your code cleaner and easier to manage. Especially when it comes to composition.

Features

• forwards calls to methods
• forwards properties (optionally including setters)
• includes inherited members
• adds overrides if neccessary

Limitations

• No indexers
• No constructors
• Ignores required keywords
• Always forwards all method overloads
• May encounter difficulties with generics
• Ignores methods starting with set_/get_ as they are typically lowered getters/setters

Usage

• add an analyzer reference to the csproj file or dll:

  <ItemGroup>
    <ProjectReference Include="..\Barion.Forwarding\Barion.Forwarding.csproj"
      OutputItemType="Analyzer"
      ReferenceOutputAssembly="false" />
  </ItemGroup>

• (optional) set <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> the generator saves the files in {BaseIntermediateOutpath}/generated (e.g. obj/Debug/net7.0/generated)
• copy the ForwardingAttributes.cs file into your project
• you might have to restart your IDE for intellisense to recognize the generated files
• check the generated files for comments in case members do not get forwarded correctly

Examples

[Forwarding] //signal for the source generator
public partial class A { // needs to be partial
  // forwards every property (getter only) and method on B
  [Forward] private B b1;
}

[Forwarding]
public partial class A {
  // forwards Foo and Bar from B
  [Forward("Foo", "Bar")] private B b1;
  
  [Forward(nameof(B.Foo), nameof(B.Bar))] // better practice
   private B b2 {get; set;} // works for properties too
}

if you want more controll use the ForwardMethodsAttribute and ForwardPropertiesAttribute

[Forwarding]
public partial class A {
  // forwards methods named Foo from B
  [ForwardMethods(nameof(B.Foo))] private B b1;
    
  // forwards the Bar property from B including it's setter
  [ForwardProperties(true, nameof(B.Bar))] 
  private B b2 {get; set;}
}

Contributions

Feel free to fork this project and submit a pull request. Your contributions will be highly appreciated.

Notes

• please link back to this repo
• GPT-4 was used in the creation of this project