Calling default methods on type parameters that are type parameterized traits does not work

[brson]

Up-to-date (forward-ported) test case

trait A<T> {
    fn g(x: T) -> T { x }
}

impl A<int> for int { }

fn f<T, V: A<T>>(i: V, j: T) -> T {
    i.g(j)
}

fn main () {
    fail_unless!(f(0, 2) == 2);
}

Original Report

This assumes #4101 is merged. Fails in trans because substs for the parameterized trait A are not handled correctly.

trait A<T> {
    fn g(x: T) -> T { move x }
}

impl int: A<int> { }

fn f<T, V: A<T>>(i: V, j: T) -> T {
    i.g(move j)
}

fn main () {
    assert f(0, 2) == 2;
}

[catamorphism]

Reproduced as of eed2ca6

[pnkfelix]

Reproduced as of c202430

[pnkfelix]

Not critical for 0.6; de-milestoning

[catamorphism]

Nominating for milestone 5, production-ready

[msullivan]

Fails in typecheck now...

[msullivan]

Oh, wait, that is because implicit self is gone. It still fails in trans.

#[allow(default_methods)];

trait A<T> {
    fn g(&self, x: T) -> T { x }
}

impl A<int> for int { }

fn f<T, V: A<T>>(i: V, j: T) -> T {
    i.g(j)
}

fn main () {
    assert!(f(0, 2) == 2);
}

is an updated version

[msullivan]

Marking that this is part of #2794 for tracking purposes.

[msullivan]

I claimed that I fixed this in an earlier commit, but I found another case that could cause a similar failure. Will be pushing a fix soon.