Problems with the 'as' operator

Recording here the issue originally raised by Paulo on the mailing list

class Foo {
    def echo() { println 10 }
}

class Bar {}

Foo.metaClass.invokeMethod = { String name, args ->
    for (arg in args) {
        println arg.getClass()
    }
}

def f = new Foo()

// This works
def bar = [key: 'foo'] as Bar
f.echo(bar)

// This throws a NullPointerException
f.echo([key: 'foo'] as Bar)

The example raised in the JIRA is the shortened version of the original issue but I think it's not the same because in my shortened example "asType" call also goes through overridden invokeMethod and since that does not delegate any further to do the actual asType, the shortened version is a little contrived.

So, the real issue to solve is the one here in the comment (raised originally on the mailing list by Paulo).

Attaching a patch for review.

Alternative patch - should be run against Roshan's test.

Looks to me like Wrapper could do with some cleanup. Remove all the commented out code which is effectively in the subclasses now and probably remove the protected field too (I suspect no one is using it but to be sure, I would deprecate in 1.7.3 first then remove in 1.8.0).

I did the trivial cleanup items but not the change on the protected field nor anything related this patch of course. We can do any remaining cleanup after the patch if needed.

Done.

It's also fixed on 1.6.9 as it seemed to me like a small bug fix - if anyone thinks otherwise, please let me know.