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// run-pass
#![allow(non_camel_case_types)]
#![allow(stable_features)]
// Issue 4691: Ensure that functional-struct-updates operates
// correctly and moves rather than copy when appropriate.
#![feature(core)]
struct ncint { v: isize }
fn ncint(v: isize) -> ncint { ncint { v: v } }
struct NoFoo { copied: isize, nocopy: ncint, }
impl NoFoo {
fn new(x:isize,y:isize) -> NoFoo { NoFoo { copied: x, nocopy: ncint(y) } }
}
struct MoveFoo { copied: isize, moved: Box<isize>, }
impl MoveFoo {
fn new(x:isize,y:isize) -> MoveFoo { MoveFoo { copied: x, moved: Box::new(y) } }
}
struct DropNoFoo { inner: NoFoo }
impl DropNoFoo {
fn new(x:isize,y:isize) -> DropNoFoo { DropNoFoo { inner: NoFoo::new(x,y) } }
}
impl Drop for DropNoFoo { fn drop(&mut self) { } }
struct DropMoveFoo { inner: MoveFoo }
impl DropMoveFoo {
fn new(x:isize,y:isize) -> DropMoveFoo { DropMoveFoo { inner: MoveFoo::new(x,y) } }
}
impl Drop for DropMoveFoo { fn drop(&mut self) { } }
fn test0() {
// just copy implicitly copyable fields from `f`, no moves
// (and thus it is okay that these are Drop; compare against
// test ui/borrowck/borrowck-struct-update-with-dtor.rs).
// Case 1: Nocopyable
let f = DropNoFoo::new(1, 2);
let b = DropNoFoo { inner: NoFoo { nocopy: ncint(3), ..f.inner }};
let c = DropNoFoo { inner: NoFoo { nocopy: ncint(4), ..f.inner }};
assert_eq!(f.inner.copied, 1);
assert_eq!(f.inner.nocopy.v, 2);
assert_eq!(b.inner.copied, 1);
assert_eq!(b.inner.nocopy.v, 3);
assert_eq!(c.inner.copied, 1);
assert_eq!(c.inner.nocopy.v, 4);
// Case 2: Owned
let f = DropMoveFoo::new(5, 6);
let b = DropMoveFoo { inner: MoveFoo { moved: Box::new(7), ..f.inner }};
let c = DropMoveFoo { inner: MoveFoo { moved: Box::new(8), ..f.inner }};
assert_eq!(f.inner.copied, 5);
assert_eq!(*f.inner.moved, 6);
assert_eq!(b.inner.copied, 5);
assert_eq!(*b.inner.moved, 7);
assert_eq!(c.inner.copied, 5);
assert_eq!(*c.inner.moved, 8);
}
fn test1() {
// copying move-by-default fields from `f`, so it moves:
let f = MoveFoo::new(11, 12);
let b = MoveFoo {moved: Box::new(13), ..f};
let c = MoveFoo {copied: 14, ..f};
assert_eq!(b.copied, 11);
assert_eq!(*b.moved, 13);
assert_eq!(c.copied, 14);
assert_eq!(*c.moved, 12);
}
fn test2() {
// move non-copyable field
let f = NoFoo::new(21, 22);
let b = NoFoo {nocopy: ncint(23), ..f};
let c = NoFoo {copied: 24, ..f};
assert_eq!(b.copied, 21);
assert_eq!(b.nocopy.v, 23);
assert_eq!(c.copied, 24);
assert_eq!(c.nocopy.v, 22);
}
pub fn main() {
test0();
test1();
test2();
}
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