rust/tests/ui/moves/issue-72649-uninit-in-loop.rs
Esteban Küber d68f2a6b71 Mention when type parameter could be Clone
```
error[E0382]: use of moved value: `t`
  --> $DIR/use_of_moved_value_copy_suggestions.rs:7:9
   |
LL | fn duplicate_t<T>(t: T) -> (T, T) {
   |                   - move occurs because `t` has type `T`, which does not implement the `Copy` trait
...
LL |     (t, t)
   |      -  ^ value used here after move
   |      |
   |      value moved here
   |
help: if `T` implemented `Clone`, you could clone the value
  --> $DIR/use_of_moved_value_copy_suggestions.rs:4:16
   |
LL | fn duplicate_t<T>(t: T) -> (T, T) {
   |                ^ consider constraining this type parameter with `Clone`
...
LL |     (t, t)
   |      - you could clone this value
help: consider restricting type parameter `T`
   |
LL | fn duplicate_t<T: Copy>(t: T) -> (T, T) {
   |                 ++++++
```

The `help` is new. On ADTs, we also extend the output with span labels:

```
error[E0507]: cannot move out of static item `FOO`
  --> $DIR/issue-17718-static-move.rs:6:14
   |
LL |     let _a = FOO;
   |              ^^^ move occurs because `FOO` has type `Foo`, which does not implement the `Copy` trait
   |
note: if `Foo` implemented `Clone`, you could clone the value
  --> $DIR/issue-17718-static-move.rs:1:1
   |
LL | struct Foo;
   | ^^^^^^^^^^ consider implementing `Clone` for this type
...
LL |     let _a = FOO;
   |              --- you could clone this value
help: consider borrowing here
   |
LL |     let _a = &FOO;
   |              +
```
2024-04-24 22:21:15 +00:00

87 lines
2.7 KiB
Rust

// Regression test for issue #72649
// Tests that we don't emit spurious
// 'value moved in previous iteration of loop' message
struct NonCopy;
//~^ NOTE if `NonCopy` implemented `Clone`
//~| NOTE if `NonCopy` implemented `Clone`
//~| NOTE if `NonCopy` implemented `Clone`
//~| NOTE if `NonCopy` implemented `Clone`
//~| NOTE consider implementing `Clone` for this type
//~| NOTE consider implementing `Clone` for this type
//~| NOTE consider implementing `Clone` for this type
//~| NOTE consider implementing `Clone` for this type
fn good() {
loop {
let value = NonCopy{};
let _used = value;
}
}
fn moved_here_1() {
loop {
let value = NonCopy{};
//~^ NOTE move occurs because `value` has type `NonCopy`, which does not implement the `Copy` trait
let _used = value;
//~^ NOTE value moved here
//~| NOTE you could clone this value
let _used2 = value; //~ ERROR use of moved value: `value`
//~^ NOTE value used here after move
}
}
fn moved_here_2() {
let value = NonCopy{};
//~^ NOTE move occurs because `value` has type `NonCopy`, which does not implement the `Copy` trait
loop { //~ NOTE inside of this loop
let _used = value;
//~^ NOTE value moved here
//~| NOTE you could clone this value
loop {
let _used2 = value; //~ ERROR use of moved value: `value`
//~^ NOTE value used here after move
}
}
}
fn moved_loop_1() {
let value = NonCopy{};
//~^ NOTE move occurs because `value` has type `NonCopy`, which does not implement the `Copy` trait
loop { //~ NOTE inside of this loop
let _used = value; //~ ERROR use of moved value: `value`
//~^ NOTE value moved here, in previous iteration of loop
//~| NOTE you could clone this value
}
}
fn moved_loop_2() {
let mut value = NonCopy{};
//~^ NOTE move occurs because `value` has type `NonCopy`, which does not implement the `Copy` trait
let _used = value;
value = NonCopy{};
loop { //~ NOTE inside of this loop
let _used2 = value; //~ ERROR use of moved value: `value`
//~^ NOTE value moved here, in previous iteration of loop
//~| NOTE you could clone this value
}
}
fn uninit_1() {
loop {
let value: NonCopy; //~ NOTE declared here
let _used = value; //~ ERROR binding `value` isn't initialized
//~^ NOTE `value` used here but it isn't initialized
}
}
fn uninit_2() {
let mut value: NonCopy; //~ NOTE declared here
loop {
let _used = value; //~ ERROR binding `value` isn't initialized
//~^ NOTE `value` used here but it isn't initialized
}
}
fn main() {}