```
error[E0277]: `()` is not a future
--> $DIR/unnecessary-await.rs:28:10
|
LL | e!().await;
| ^^^^^ `()` is not a future
|
= help: the trait `Future` is not implemented for `()`
= note: () must be a future or must implement `IntoFuture` to be awaited
= note: required for `()` to implement `IntoFuture`
help: remove the `.await`
|
LL - e!().await;
LL + e!();
|
```
```
error[E0277]: the trait bound `String: Copy` is not satisfied
--> $DIR/const-fn-in-vec.rs:1:47
|
LL | static _MAYBE_STRINGS: [Option<String>; 5] = [None; 5];
| ^^^^ the trait `Copy` is not implemented for `String`
|
= note: required for `Option<String>` to implement `Copy`
= note: the `Copy` trait is required because this value will be copied for each element of the array
help: create an inline `const` block
|
LL | static _MAYBE_STRINGS: [Option<String>; 5] = [const { None }; 5];
| +++++++ +
```
Remove the "which is required by `{root_obligation}`" post-script in
"the trait `X` is not implemented for `Y`" explanation in E0277. This
information is already conveyed in the notes explaining requirements,
making it redundant while making the text (particularly in labels)
harder to read.
```
error[E0277]: the trait bound `NotCopy: Copy` is not satisfied
--> $DIR/wf-static-type.rs:10:13
|
LL | static FOO: IsCopy<Option<NotCopy>> = IsCopy { t: None };
| ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopy`
|
= note: required for `Option<NotCopy>` to implement `Copy`
note: required by a bound in `IsCopy`
--> $DIR/wf-static-type.rs:7:17
|
LL | struct IsCopy<T:Copy> { t: T }
| ^^^^ required by this bound in `IsCopy`
```
vs the prior
```
error[E0277]: the trait bound `NotCopy: Copy` is not satisfied
--> $DIR/wf-static-type.rs:10:13
|
LL | static FOO: IsCopy<Option<NotCopy>> = IsCopy { t: None };
| ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopy`, which is required by `Option<NotCopy>: Copy`
|
= note: required for `Option<NotCopy>` to implement `Copy`
note: required by a bound in `IsCopy`
--> $DIR/wf-static-type.rs:7:17
|
LL | struct IsCopy<T:Copy> { t: T }
| ^^^^ required by this bound in `IsCopy`
```
Expand the primary span of E0277 when the immediate unmet bound is not what the user wrote:
```
error[E0277]: the trait bound `i32: Bar` is not satisfied
--> f100.rs:6:6
|
6 | <i32 as Foo>::foo();
| ^^^ the trait `Bar` is not implemented for `i32`, which is required by `i32: Foo`
|
help: this trait has no implementations, consider adding one
--> f100.rs:2:1
|
2 | trait Bar {}
| ^^^^^^^^^
note: required for `i32` to implement `Foo`
--> f100.rs:3:14
|
3 | impl<T: Bar> Foo for T {}
| --- ^^^ ^
| |
| unsatisfied trait bound introduced here
```
Fix#40120.
