From 218caa410aa38c29984be31a5229b9fa717560ee Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:19:13 +0200 Subject: Merging upstream version 1.68.2+dfsg1. Signed-off-by: Daniel Baumann --- tests/ui/borrowck/borrowck-closures-unique.rs | 54 +++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 tests/ui/borrowck/borrowck-closures-unique.rs (limited to 'tests/ui/borrowck/borrowck-closures-unique.rs') diff --git a/tests/ui/borrowck/borrowck-closures-unique.rs b/tests/ui/borrowck/borrowck-closures-unique.rs new file mode 100644 index 000000000..67f91dfa8 --- /dev/null +++ b/tests/ui/borrowck/borrowck-closures-unique.rs @@ -0,0 +1,54 @@ +// Tests that a closure which requires mutable access to the referent +// of an `&mut` requires a "unique" borrow -- that is, the variable to +// be borrowed (here, `x`) will not be borrowed *mutably*, but +// may be *immutable*, but we cannot allow +// multiple borrows. + + + +fn get(x: &isize) -> isize { + *x +} + +fn set(x: &mut isize) -> isize { + *x +} + +fn a(x: &mut isize) { + let c1 = || get(x); + let c2 = || get(x); + c1(); + c2(); +} + +fn b(x: &mut isize) { + let c1 = || get(x); + let c2 = || set(x); //~ ERROR closure requires unique access to `x` + c1; +} + +fn c(x: &mut isize) { + let c1 = || get(x); + let c2 = || { get(x); set(x); }; //~ ERROR closure requires unique access to `x` + c1; +} + +fn d(x: &mut isize) { + let c1 = || set(x); + let c2 = || set(x); //~ ERROR two closures require unique access to `x` at the same time + c1; +} + +fn e(x: &'static mut isize) { + let c1 = |y: &'static mut isize| x = y; + //~^ ERROR cannot assign to `x`, as it is not declared as mutable + c1; +} + +fn f(x: &'static mut isize) { + let c1 = || x = panic!(); // OK assignment is unreachable. + c1; +} + +fn main() { +} -- cgit v1.2.3