Wrong delegate type returned (with closure)

[exyi]

Hi! Awesome project, I tried to migrate DotVVM to this expression compiler and the performance figures are awesome. CompileFast is literally faster than .Compile(preferInterpretation: true) (of course, not counting the execution time)

However, I encountered few bugs, one of them can be replicated with this test:

delegate string Command();
[Test]
public void Bug3()
{
  var p = Parameter(typeof(string), "vm");
  var expr = Lambda<Func<string, Command>>(Lambda<Command>(p), p);


  var ff = expr.Compile();
  Assert.IsInstanceOf<Command>(ff(null));
  var f = expr.CompileFast();
  Assert.IsInstanceOf<Command>(f(null));
}

The fast expression always returns Func<string> even though it should return Command. If I don't use the parameter inside the lambda, it works correctly and returns Command

[dadhi]

@exyi Hi,

Thanks for the simple repro. Will look when time permits.