diff --git a/src/test/compile-fail/issue-23338-locals-die-before-temps-of-body.rs b/src/test/compile-fail/issue-23338-locals-die-before-temps-of-body.rs new file mode 100644 index 00000000000..993893438e5 --- /dev/null +++ b/src/test/compile-fail/issue-23338-locals-die-before-temps-of-body.rs @@ -0,0 +1,36 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// This is just checking that we still reject code where temp values +// are borrowing values for longer than they will be around. +// +// Compare to run-pass/issue-23338-params-outlive-temps-of-body.rs + +use std::cell::RefCell; + +fn foo(x: RefCell) -> String { + let y = x; + y.borrow().clone() //~ ERROR `y` does not live long enough +} + +fn foo2(x: RefCell) -> String { + let ret = { + let y = x; + y.borrow().clone() //~ ERROR `y` does not live long enough + }; + ret +} + +fn main() { + let r = RefCell::new(format!("data")); + assert_eq!(foo(r), "data"); + let r = RefCell::new(format!("data")); + assert_eq!(foo2(r), "data"); +} diff --git a/src/test/run-pass/issue-23338-ensure-param-drop-order.rs b/src/test/run-pass/issue-23338-ensure-param-drop-order.rs new file mode 100644 index 00000000000..0815ff084fb --- /dev/null +++ b/src/test/run-pass/issue-23338-ensure-param-drop-order.rs @@ -0,0 +1,171 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// ignore-pretty : (#23623) problems when ending with // comments + +// This test is ensuring that parameters are indeed dropped after +// temporaries in a fn body. + +use std::cell::RefCell; + +use self::d::D; + +pub fn main() { + let log = RefCell::new(vec![]); + d::println(&format!("created empty log")); + test(&log); + + assert_eq!(&log.borrow()[..], + [ + // created empty log + // +-- Make D(da_0, 0) + // | +-- Make D(de_1, 1) + // | | calling foo + // | | entered foo + // | | +-- Make D(de_2, 2) + // | | | +-- Make D(da_1, 3) + // | | | | +-- Make D(de_3, 4) + // | | | | | +-- Make D(de_4, 5) + 3, // | | | +-- Drop D(da_1, 3) + // | | | | | + 4, // | | | +-- Drop D(de_3, 4) + // | | | | + // | | | | eval tail of foo + // | | | +-- Make D(de_5, 6) + // | | | | +-- Make D(de_6, 7) + 6, // | | | +-- Drop D(de_5, 6) + // | | | | | + 5, // | | | | +-- Drop D(de_4, 5) + // | | | | + 2, // | | +-- Drop D(de_2, 2) + // | | | + 1, // | +-- Drop D(de_1, 1) + // | | + 0, // +-- Drop D(da_0, 0) + // | + // | result D(de_6, 7) + 7 // +-- Drop D(de_6, 7) + + ]); +} + +fn test<'a>(log: d::Log<'a>) { + let da = D::new("da", 0, log); + let de = D::new("de", 1, log); + d::println(&format!("calling foo")); + let result = foo(da, de); + d::println(&format!("result {}", result)); +} + +fn foo<'a>(da0: D<'a>, de1: D<'a>) -> D<'a> { + d::println(&format!("entered foo")); + let de2 = de1.incr(); // creates D(de_2, 2) + let de4 = { + let _da1 = da0.incr(); // creates D(da_1, 3) + de2.incr().incr() // creates D(de_3, 4) and D(de_4, 5) + }; + d::println(&format!("eval tail of foo")); + de4.incr().incr() // creates D(de_5, 6) and D(de_6, 7) +} + +// This module provides simultaneous printouts of the dynamic extents +// of all of the D values, in addition to logging the order that each +// is dropped. + +const PREF_INDENT: u32 = 16; + +pub mod d { + #![allow(unused_parens)] + use std::fmt; + use std::mem; + use std::cell::RefCell; + + static mut counter: u32 = 0; + static mut trails: u64 = 0; + + pub type Log<'a> = &'a RefCell>; + + pub fn current_width() -> u32 { + unsafe { max_width() - trails.leading_zeros() } + } + + pub fn max_width() -> u32 { + unsafe { + (mem::size_of_val(&trails)*8) as u32 + } + } + + pub fn indent_println(my_trails: u32, s: &str) { + let mut indent: String = String::new(); + for i in 0..my_trails { + unsafe { + if trails & (1 << i) != 0 { + indent = indent + "| "; + } else { + indent = indent + " "; + } + } + } + println!("{}{}", indent, s); + } + + pub fn println(s: &str) { + indent_println(super::PREF_INDENT, s); + } + + fn first_avail() -> u32 { + unsafe { + for i in 0..64 { + if trails & (1 << i) == 0 { + return i; + } + } + } + panic!("exhausted trails"); + } + + pub struct D<'a> { + name: &'static str, i: u32, uid: u32, trail: u32, log: Log<'a> + } + + impl<'a> fmt::Display for D<'a> { + fn fmt(&self, w: &mut fmt::Formatter) -> fmt::Result { + write!(w, "D({}_{}, {})", self.name, self.i, self.uid) + } + } + + impl<'a> D<'a> { + pub fn new(name: &'static str, i: u32, log: Log<'a>) -> D<'a> { + unsafe { + let trail = first_avail(); + let ctr = counter; + counter += 1; + trails |= (1 << trail); + let ret = D { + name: name, i: i, log: log, uid: ctr, trail: trail + }; + indent_println(trail, &format!("+-- Make {}", ret)); + ret + } + } + pub fn incr(&self) -> D<'a> { + D::new(self.name, self.i + 1, self.log) + } + } + + impl<'a> Drop for D<'a> { + fn drop(&mut self) { + unsafe { trails &= !(1 << self.trail); }; + self.log.borrow_mut().push(self.uid); + indent_println(self.trail, &format!("+-- Drop {}", self)); + indent_println(::PREF_INDENT, ""); + } + } +} diff --git a/src/test/run-pass/issue-23338-params-outlive-temps-of-body.rs b/src/test/run-pass/issue-23338-params-outlive-temps-of-body.rs new file mode 100644 index 00000000000..cb9e852e526 --- /dev/null +++ b/src/test/run-pass/issue-23338-params-outlive-temps-of-body.rs @@ -0,0 +1,39 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// This is largely checking that we now accept code where temp values +// are borrowing from the input parameters (the `foo` case below). +// +// Compare to run-pass/issue-23338-params-outlive-temps-of-body.rs +// +// (The `foo2` case is just for parity with the above test, which +// shows what happens when you move the `y`-binding to the inside of +// the inner block.) + +use std::cell::RefCell; + +fn foo(x: RefCell) -> String { + x.borrow().clone() +} + +fn foo2(x: RefCell) -> String { + let y = x; + let ret = { + y.borrow().clone() + }; + ret +} + +pub fn main() { + let r = RefCell::new(format!("data")); + assert_eq!(foo(r), "data"); + let r = RefCell::new(format!("data")); + assert_eq!(foo2(r), "data"); +}