diff options
Diffstat (limited to 'tests')
| -rw-r--r-- | tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.rs | 46 | ||||
| -rw-r--r-- | tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.stderr | 89 |
2 files changed, 135 insertions, 0 deletions
diff --git a/tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.rs b/tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.rs new file mode 100644 index 00000000000..934aac8383d --- /dev/null +++ b/tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.rs @@ -0,0 +1,46 @@ +// https://github.com/rust-lang/rust/issues/133941 +use std::marker::PhantomData; + +struct Bar<'a>(PhantomData<&'a mut i32>); + +impl<'a> Drop for Bar<'a> { + fn drop(&mut self) {} +} + +struct Foo(); + +impl Foo { + fn f(&mut self) -> Option<Bar<'_>> { + None + } + + fn g(&mut self) {} +} + +fn main() { + let mut foo = Foo(); + while let Some(_) = foo.f() { + //~^ HELP matches! + foo.g(); + //~^ ERROR [E0499] + } + if let Some(_) = foo.f() { + //~^ HELP matches! + foo.g(); + //~^ ERROR [E0499] + } + while let Some(_x) = foo.f() { + foo.g(); + //~^ ERROR [E0499] + } + if let Some(_x) = foo.f() { + foo.g(); + //~^ ERROR [E0499] + } + while let Some(_x) = {let _x = foo.f(); foo.g(); None::<()>} { + //~^ ERROR [E0499] + } + if let Some(_x) = {let _x = foo.f(); foo.g(); None::<()>} { + //~^ ERROR [E0499] + } +} diff --git a/tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.stderr b/tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.stderr new file mode 100644 index 00000000000..bb21caccbaf --- /dev/null +++ b/tests/ui/borrowck/already-borrowed-as-mutable-if-let-133941.stderr @@ -0,0 +1,89 @@ +error[E0499]: cannot borrow `foo` as mutable more than once at a time + --> $DIR/already-borrowed-as-mutable-if-let-133941.rs:24:9 + | +LL | while let Some(_) = foo.f() { + | ------- + | | + | first mutable borrow occurs here + | a temporary with access to the first borrow is created here ... +LL | +LL | foo.g(); + | ^^^ second mutable borrow occurs here +LL | +LL | } + | - ... and the first borrow might be used here, when that temporary is dropped and runs the destructor for type `Option<Bar<'_>>` + | +help: consider using the `matches!` macro + | +LL | while matches!(foo.f(), Some(_)) { + | ~~~~~~~~~~~~~~~~~~~~~~~~~~ + +error[E0499]: cannot borrow `foo` as mutable more than once at a time + --> $DIR/already-borrowed-as-mutable-if-let-133941.rs:29:9 + | +LL | if let Some(_) = foo.f() { + | ------- + | | + | first mutable borrow occurs here + | a temporary with access to the first borrow is created here ... +LL | +LL | foo.g(); + | ^^^ second mutable borrow occurs here +LL | +LL | } + | - ... and the first borrow might be used here, when that temporary is dropped and runs the destructor for type `Option<Bar<'_>>` + | +help: consider using the `matches!` macro + | +LL | if matches!(foo.f(), Some(_)) { + | ~~~~~~~~~~~~~~~~~~~~~~~~~~ + +error[E0499]: cannot borrow `foo` as mutable more than once at a time + --> $DIR/already-borrowed-as-mutable-if-let-133941.rs:33:9 + | +LL | while let Some(_x) = foo.f() { + | ------- + | | + | first mutable borrow occurs here + | a temporary with access to the first borrow is created here ... +LL | foo.g(); + | ^^^ second mutable borrow occurs here +LL | +LL | } + | - ... and the first borrow might be used here, when that temporary is dropped and runs the destructor for type `Option<Bar<'_>>` + +error[E0499]: cannot borrow `foo` as mutable more than once at a time + --> $DIR/already-borrowed-as-mutable-if-let-133941.rs:37:9 + | +LL | if let Some(_x) = foo.f() { + | ------- + | | + | first mutable borrow occurs here + | a temporary with access to the first borrow is created here ... +LL | foo.g(); + | ^^^ second mutable borrow occurs here +LL | +LL | } + | - ... and the first borrow might be used here, when that temporary is dropped and runs the destructor for type `Option<Bar<'_>>` + +error[E0499]: cannot borrow `foo` as mutable more than once at a time + --> $DIR/already-borrowed-as-mutable-if-let-133941.rs:40:45 + | +LL | while let Some(_x) = {let _x = foo.f(); foo.g(); None::<()>} { + | --- ^^^ - first borrow might be used here, when `_x` is dropped and runs the destructor for type `Option<Bar<'_>>` + | | | + | | second mutable borrow occurs here + | first mutable borrow occurs here + +error[E0499]: cannot borrow `foo` as mutable more than once at a time + --> $DIR/already-borrowed-as-mutable-if-let-133941.rs:43:42 + | +LL | if let Some(_x) = {let _x = foo.f(); foo.g(); None::<()>} { + | --- ^^^ - first borrow might be used here, when `_x` is dropped and runs the destructor for type `Option<Bar<'_>>` + | | | + | | second mutable borrow occurs here + | first mutable borrow occurs here + +error: aborting due to 6 previous errors + +For more information about this error, try `rustc --explain E0499`. |