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|
#![allow(dead_code)]
#[macro_use]
extern crate rental;
use std::cell::RefCell;
use std::rc::Rc;
pub struct Foo {
i: i32,
d: Rc<RefCell<String>>,
}
pub struct Bar<'a> {
foo: &'a Foo,
d: Rc<RefCell<String>>,
}
pub struct Baz<'a: 'b, 'b> {
bar: &'b Bar<'a>,
d: Rc<RefCell<String>>,
}
pub struct Qux<'a: 'b, 'b: 'c, 'c> {
baz: &'c Baz<'a, 'b>,
d: Rc<RefCell<String>>,
}
pub struct Xyzzy<'a: 'b, 'b: 'c, 'c: 'd, 'd> {
qux: &'d Qux<'a, 'b, 'c>,
d: Rc<RefCell<String>>,
}
impl Foo {
pub fn borrow<'a>(&'a self) -> Bar<'a> { Bar { foo: self, d: self.d.clone() } }
}
impl Drop for Foo {
fn drop(&mut self) {
self.d.borrow_mut().push_str("Foo");
}
}
impl<'a> Bar<'a> {
pub fn borrow<'b>(&'b self) -> Baz<'a, 'b> { Baz { bar: self, d: self.d.clone() } }
}
impl<'a> Drop for Bar<'a> {
fn drop(&mut self) {
self.d.borrow_mut().push_str("Bar");
}
}
impl<'a: 'b, 'b> Baz<'a, 'b> {
pub fn borrow<'c>(&'c self) -> Qux<'a, 'b, 'c> { Qux { baz: self, d: self.d.clone() } }
}
impl<'a: 'b, 'b> Drop for Baz<'a, 'b> {
fn drop(&mut self) {
self.d.borrow_mut().push_str("Baz");
}
}
impl<'a: 'b, 'b: 'c, 'c> Qux<'a, 'b, 'c> {
pub fn borrow<'d>(&'d self) -> Xyzzy<'a, 'b, 'c, 'd> { Xyzzy { qux: self, d: self.d.clone() } }
}
impl<'a: 'b, 'b: 'c, 'c> Drop for Qux<'a, 'b, 'c> {
fn drop(&mut self) {
self.d.borrow_mut().push_str("Qux");
}
}
impl<'a: 'b, 'b: 'c, 'c: 'd, 'd> Drop for Xyzzy<'a, 'b, 'c, 'd> {
fn drop(&mut self) {
self.d.borrow_mut().push_str("Xyzzy");
}
}
rental! {
pub mod rentals {
use super::*;
#[rental]
pub struct DropTestRent {
foo: Box<Foo>,
bar: Box<Bar<'foo>>,
baz: Box<Baz<'foo, 'bar>>,
qux: Box<Qux<'foo, 'bar, 'baz>>,
xyzzy: Xyzzy<'foo, 'bar, 'baz, 'qux>,
}
}
}
#[test]
fn drop_order() {
let d = Rc::new(RefCell::new(String::new()));
{
let foo = Foo { i: 5, d: d.clone() };
let _ = rentals::DropTestRent::new(
Box::new(foo),
|foo| Box::new(foo.borrow()),
|bar, _| Box::new(bar.borrow()),
|baz, _, _| Box::new(baz.borrow()),
|qux, _, _, _| qux.borrow()
);
}
assert_eq!(*d.borrow(), "XyzzyQuxBazBarFoo");
let d = Rc::new(RefCell::new(String::new()));
{
let foo = Foo { i: 5, d: d.clone() };
let r = rentals::DropTestRent::new(
Box::new(foo),
|foo| Box::new(foo.borrow()),
|bar, _| Box::new(bar.borrow()),
|baz, _, _| Box::new(baz.borrow()),
|qux, _, _, _| qux.borrow()
);
let _head = r.into_head();
}
assert_eq!(*d.borrow(), "XyzzyQuxBazBarFoo");
}
|
