rust/src/test/compile-fail/regions-infer-covariance-due-to-decl.rs
Niko Matsakis 872ce47955 Fallout: tests. As tests frequently elide things, lots of changes
here.  Some of this may have been poorly rebased, though I tried to be
careful and preserve the spirit of the test.
2015-02-18 10:25:28 -05:00

36 lines
1.2 KiB
Rust

// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test that a type which is covariant with respect to its region
// parameter yields an error when used in a contravariant way.
//
// Note: see variance-regions-*.rs for the tests that check that the
// variance inference works in the first place.
use std::marker;
struct Covariant<'a> {
marker: marker::PhantomData<fn(&'a ())>
}
fn use_<'short,'long>(c: Covariant<'long>,
s: &'short isize,
l: &'long isize,
_where:Option<&'short &'long ()>) {
// Test whether Covariant<'long> <: Covariant<'short>. Since
// 'short <= 'long, this would be true if the Covariant type were
// contravariant with respect to its parameter 'a.
let _: Covariant<'short> = c; //~ ERROR mismatched types
}
fn main() {}