Beyond.NET interface adapter

CSharp.cs

// This is declared by the user.
public interface IInterface1
{
    void MethodInIInterface1();
}

// This should be auto-generated to allow Swift to provide implementations for .NET interfaces.
public class IInterface1_Adapter : IInterface1
{
    public delegate void MethodInIInterface1_Delegate();
    private MethodInIInterface1_Delegate _MethodInIInterface1_Adapter;

    public IInterface1_Adapter(MethodInIInterface1_Delegate methodInIInterface1_Adapter)
    {
        _MethodInIInterface1_Adapter = methodInIInterface1_Adapter;
    }
    
    public void MethodInIInterface1()
    {
        _MethodInIInterface1_Adapter();
    }
}

// This is declared by the user.
public class TypeThatUsesInterfaces
{
    public void CallMethod1InIInterface1(IInterface1 interface1)
    {
        interface1.MethodInIInterface1();
    }
}

Swift.swift

func testInterfaceAdapter() throws {
    let typeThatUsesInterfaces = try Beyond_NET_Sample_TypeThatUsesInterfaces()
    
    let methodInIInterface1CalledExpectation = expectation(description: "IInterface1.MethodInIInterface1 called in Swift")
    
    // NOTE: Compiler ensures we provide all interface requirements.
    let interface1Adapter = try Beyond_NET_Sample_IInterface1_Adapter(.init({
        print("IInterface1.MethodInIInterface1 called in Swift")
        
        methodInIInterface1CalledExpectation.fulfill()
    }))
    
    try typeThatUsesInterfaces.callMethod1InIInterface1(try interface1Adapter.castTo())
    
    wait(for: [ methodInIInterface1CalledExpectation ])
}