Roslyn 语法重写器是如何集成的？

Question

I'd like to use a Roslyn syntax rewriter in an existing .NET Core project. However, I'm unsure how to go about integrating it. For analysis, I have a separate NuGet package that gets referenced by the project; this works well enough. However, I can't find any documentation on how to integrate a syntax rewriter with the existing workflow.

Since this is a .NET Core project, I'm currently compiling using both Visual Studio and the dotnet command line tool. The project is a csproj referencing netcoreapp3.0 (preview). I'd like to integrate my syntax rewriter such that whenever I run dotnet build or press F5/F6 in Visual Studio, the syntax rewriter runs. While there's a lot of documentation for building a syntax rewriter, there doesn't seem to be any for integrating it into the build process.

To be clear, here's what I'm trying to do:

1. I will eventually have a syntax rewriter based on this documentation . It transforms the code at compile-time.
2. I have a C# project with code that I would like to transform.
3. I would like to take the syntax rewriter from step #1 and run it automatically when I compile the project from step #2.

For example, say I have the following code:

class A
{
    [SomeAttribute]
    void Method()
    {
    }
}

I can easily make a syntax rewriter that takes this code in the form of a syntax tree, alters it, and produces code corresponding to the following syntax tree:

class A
{
    [SomeAttribute]
    [AnotherAttribute]
    void Method()
    {
        SomeCode();
    }
}

Optionally, I can produce a syntax tree by taking the code as a string input, as well as render the final syntax tree to a string. That's easy enough.

What I can't find instructions for is automating this process. I don't want to have to manually run an EXE each time I build; I want to be able to integrate it into the default build process, and I'm looking for the correct way to do that.

Ideally, this would also involve rewriting the syntax tree live in Visual Studio as the developer writes code. This would permit IntelliSense to operate on the final syntax tree, rather than what the developer has written. However, I don't know if this part is possible to achieve.

Answer 1

Syntax rewriters are not things that are part of the build. They are typically used to build code fixes that are run inside Visual Studio.