diff options
| -rw-r--r-- | src/librustc/ty/context.rs | 14 | ||||
| -rw-r--r-- | src/test/ui/borrowck/issue-52967-edition-2018-needs-two-phase-borrows.rs | 32 |
2 files changed, 43 insertions, 3 deletions
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs index 98568f860a4..89f3d7c30db 100644 --- a/src/librustc/ty/context.rs +++ b/src/librustc/ty/context.rs @@ -1395,10 +1395,18 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> { } /// If true, we should enable two-phase borrows checks. This is - /// done with either `-Ztwo-phase-borrows` or with - /// `#![feature(nll)]`. + /// done with either: `-Ztwo-phase-borrows`, `#![feature(nll)]`, + /// or by opting into an edition after 2015. pub fn two_phase_borrows(self) -> bool { - self.features().nll || self.sess.opts.debugging_opts.two_phase_borrows + if self.features().nll || self.sess.opts.debugging_opts.two_phase_borrows { + return true; + } + + match self.sess.edition() { + Edition::Edition2015 => false, + Edition::Edition2018 => true, + _ => true, + } } /// What mode(s) of borrowck should we run? AST? MIR? both? diff --git a/src/test/ui/borrowck/issue-52967-edition-2018-needs-two-phase-borrows.rs b/src/test/ui/borrowck/issue-52967-edition-2018-needs-two-phase-borrows.rs new file mode 100644 index 00000000000..c39fff2644d --- /dev/null +++ b/src/test/ui/borrowck/issue-52967-edition-2018-needs-two-phase-borrows.rs @@ -0,0 +1,32 @@ +// Copyright 2018 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. + +// This is a regression test for #52967, where we discovered that in +// the initial deployment of NLL for the 2018 edition, I forgot to +// turn on two-phase-borrows in addition to `-Z borrowck=migrate`. + +// revisions: ast zflags edition +//[zflags]compile-flags: -Z borrowck=migrate -Z two-phase-borrows +//[edition]compile-flags: --edition 2018 + +// run-pass + +fn the_bug() { + let mut stuff = ("left", "right"); + match stuff { + (ref mut left, _) if *left == "left" => { *left = "new left"; } + _ => {} + } + assert_eq!(stuff, ("new left", "right")); +} + +fn main() { + the_bug(); +} |