| // Copyright 2015 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. |
| |
| // Regression test for issue #21245. Check that we are able to infer |
| // the types in these examples correctly. It used to be that |
| // insufficient type propagation caused the type of the iterator to be |
| // incorrectly unified with the `*const` type to which it is coerced. |
| |
| // pretty-expanded FIXME #23616 |
| |
| use std::ptr; |
| |
| trait IntoIterator { |
| type Iter: Iterator; |
| |
| fn into_iter2(self) -> Self::Iter; |
| } |
| |
| impl<I> IntoIterator for I where I: Iterator { |
| type Iter = I; |
| |
| fn into_iter2(self) -> I { |
| self |
| } |
| } |
| |
| fn desugared_for_loop_bad<T>(v: Vec<T>) { |
| match IntoIterator::into_iter2(v.iter()) { |
| mut iter => { |
| loop { |
| match ::std::iter::Iterator::next(&mut iter) { |
| ::std::option::Option::Some(x) => { |
| unsafe { ptr::read(x); } |
| }, |
| ::std::option::Option::None => break |
| } |
| } |
| } |
| } |
| } |
| |
| fn desugared_for_loop_good<T>(v: Vec<T>) { |
| match v.iter().into_iter() { |
| mut iter => { |
| loop { |
| match ::std::iter::Iterator::next(&mut iter) { |
| ::std::option::Option::Some(x) => { |
| unsafe { ptr::read(x); } |
| }, |
| ::std::option::Option::None => break |
| } |
| } |
| } |
| } |
| } |
| |
| fn main() {} |