GeneratorTest.cs

using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using System.Reflection;
using Xunit;
using FluentAssertions;

namespace MKLNET.WrapperGenerator.Tests;

public class GeneratorTest
{
    [Fact]
    public void GeneratorShouldAcceptPinvokeStatementAndNotProduceErrors()
    {
        var inputCompilation = CreateCompilation(@"
using System.Runtime.InteropServices;

namespace MKLNET;

public static partial class BlasOption2
{
    public static class Unsafe
    {
        [DllImport(""dummy.dll"", CallingConvention = CallingConvention.Cdecl, ExactSpelling = true, EntryPoint = ""dummy"")]
        public static unsafe extern void dummy(int M, int N,
            int K, double alpha, double* A,
            int lda, double* B, int ldb,
            double beta, double* C, int ldc);

        public static unsafe extern void summy(int N, double* A, double* B);
    }
}
");

        var generator = new WrapperGenerator();
        GeneratorDriver driver = CSharpGeneratorDriver.Create(generator);

        driver = driver.RunGeneratorsAndUpdateCompilation(inputCompilation, out var outputCompilation, out var diagnostics);

        diagnostics.Should().BeEmpty();
        outputCompilation.SyntaxTrees.Should().HaveCount(2); // input and generated
        outputCompilation.GetDiagnostics().Should().BeEmpty();

        var runResult = driver.GetRunResult();

        runResult.GeneratedTrees.Should().HaveCount(1);
        runResult.Diagnostics.Should().BeEmpty();

        var generatorResult = runResult.Results[0];

        generatorResult.Generator.Should().BeSameAs(generator);
        generatorResult.Diagnostics.Should().BeEmpty();
        generatorResult.GeneratedSources.Should().ContainSingle()
            .Which.SourceText.ToString().Should().Contain(
                "///<remarks>" +
                "This version infers the length parameter <c>N</c> from <paramref name=\"A\" />'s length.</remarks>");
        generatorResult.Exception.Should().BeNull();
    }

    private static Compilation CreateCompilation(string source)
        => CSharpCompilation.Create("compilation",
            new[] { CSharpSyntaxTree.ParseText(source) },
            new[] { MetadataReference.CreateFromFile(typeof(Binder).GetTypeInfo().Assembly.Location) },
            new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary, allowUnsafe: true, warningLevel: 0));
}