mirror of https://github.com/rust-lang/rust
68 lines
1.3 KiB
Rust
68 lines
1.3 KiB
Rust
//@ run-pass
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#![allow(non_snake_case)]
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use std::rc::Rc;
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use std::cell::Cell;
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struct Field {
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number: usize,
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state: Rc<Cell<usize>>
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}
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impl Field {
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fn new(number: usize, state: Rc<Cell<usize>>) -> Field {
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Field {
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number: number,
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state: state
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}
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}
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}
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impl Drop for Field {
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fn drop(&mut self) {
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println!("Dropping field {}", self.number);
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assert_eq!(self.state.get(), self.number);
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self.state.set(self.state.get()+1);
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}
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}
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struct NoDropImpl {
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_one: Field,
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_two: Field,
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_three: Field
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}
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struct HasDropImpl {
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_one: Field,
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_two: Field,
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_three: Field
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}
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impl Drop for HasDropImpl {
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fn drop(&mut self) {
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println!("HasDropImpl.drop()");
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assert_eq!(self._one.state.get(), 0);
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self._one.state.set(1);
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}
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}
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pub fn main() {
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let state = Rc::new(Cell::new(1));
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let noImpl = NoDropImpl {
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_one: Field::new(1, state.clone()),
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_two: Field::new(2, state.clone()),
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_three: Field::new(3, state.clone())
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};
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drop(noImpl);
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assert_eq!(state.get(), 4);
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state.set(0);
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let hasImpl = HasDropImpl {
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_one: Field::new(1, state.clone()),
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_two: Field::new(2, state.clone()),
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_three: Field::new(3, state.clone())
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};
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drop(hasImpl);
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assert_eq!(state.get(), 4);
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}
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