Also, remove the explicit code detecting borrows over a yield. It
turns out not to be necessary -- any such borrow winds up with a
lifetime that is part of the generator type, and therefore which will
outlive the generator expression itself, which yields an
`err_out_of_scope`. So instead we intercept those errors and display
them in a nicer way.
Extended error message for mut borrow conflicts in loops
RFC issue: https://github.com/rust-lang/rfcs/issues/2080
The error message for multiple mutable borrows on the same value over loop iterations now makes it clear that the conflict comes from the borrow outlasting the loop. The wording of the error is based on the special case of the moved-value error for a value moved in a loop. Following the example of that error, the code remains the same for the special case.
This is mainly because I felt the current message is confusing in the loop case : https://github.com/rust-lang/rust/issues/43437. It's not clear that the two conflicting borrows are in different iterations of the loop, and instead it just looks like the compiler has an issue with a single line.
Point at path segment on module not found
Point at the correct path segment on a import statement where a module
doesn't exist.
New output:
```rust
error[E0432]: unresolved import `std::bar`
--> <anon>:1:10
|
1 | use std::bar::{foo1, foo2};
| ^^^ Could not find `bar` in `std`
```
instead of:
```rust
error[E0432]: unresolved import `std::bar::foo1`
--> <anon>:1:16
|
1 | use std::bar::{foo1, foo2};
| ^^^^ Could not find `bar` in `std`
error[E0432]: unresolved import `std::bar::foo2`
--> <anon>:1:22
|
1 | use std::bar::{foo1, foo2};
| ^^^^ Could not find `bar` in `std`
```
Fix#43040.
Make the "main" constructors of NonZero/Shared/Unique return Option
Per discussion in https://github.com/rust-lang/rust/issues/27730#issuecomment-303939441.
This is a breaking change to unstable APIs.
The old behavior is still available under the name `new_unchecked`. Note that only that one can be `const fn`, since `if` is currently not allowed in constant contexts.
In the case of `NonZero` this requires adding a new `is_zero` method to the `Zeroable` trait. I mildly dislike this, but it’s not much worse than having a `Zeroable` trait in the first place. `Zeroable` and `NonZero` are both unstable, this can be reworked later.
Point at the correct path segment on a import statement where a module
doesn't exist.
New output:
```rust
error[E0432]: unresolved import `std::bar`
--> <anon>:1:10
|
1 | use std::bar::{foo1, foo2};
| ^^^ Could not find `bar` in `std`
```
instead of:
```rust
error[E0432]: unresolved import `std::bar::foo1`
--> <anon>:1:16
|
1 | use std::bar::{foo1, foo2};
| ^^^^ Could not find `bar` in `std`
error[E0432]: unresolved import `std::bar::foo2`
--> <anon>:1:22
|
1 | use std::bar::{foo1, foo2};
| ^^^^ Could not find `bar` in `std`
```
Point at `:` when using it instead of `;`
When triggering type ascription in such a way that we can infer a
statement end was intended, add a suggestion for the change. Always
point out the reason for the expectation of a type is due to type
ascription.
Fix#42057, #41928.
Less verbose output for unused arguments
Closes#37718
This is my first contribution to rust, so sorry if I'm missing anything!
The output now looks like this:
<img width="831" alt="screen shot 2017-07-18 at 5 01 32 pm" src="https://user-images.githubusercontent.com/12972285/28347566-dbfa9962-6c05-11e7-8730-c2e8062a04cc.png">
It's not the prettiest, but whenever #41850 gets resolved, this should be able to be improved.
**EDIT:** This also does not seem
r? @Mark-Simulacrum
Now there's a way to add suggestions that hide the suggested code when
presented inline, to avoid weird wording when short code snippets are
added at the end.
The produced paths aren't stable between builds, since
reporting paths inside resolve, before resolve is finished
might produce paths resolved to type aliases instead of
the concrete type.
Compile-fail tests can match just parts of messages, so they
don't "suffer" from this issue.
This is just a workaround, the instability should be fixed
in the future.
When triggering type ascription in such a way that we can infer a
statement end was intended, add a suggestion for the change. Always
point out the reason for the expectation of a type is due to type
ascription.
We want the suggested replacement (which IDE tooling and such might offer to
automatically swap in) to, like, actually be correct: suggesting `MyVariant(x)`
when the actual fix is `MyEnum::MyVariant(x)` might be better than nothing, but
Rust is supposed to be the future of computing: we're better than better than
nothing.
As an exceptional case, we excise the prelude path, preferring to suggest
`Some` or `Ok` rather than `std::prelude::v1::Some` and
`std::prelude::v2::Ok`. (It's not worth the effort to future-proof against
hypothetical preludes v2, v3, &c.: we trust our successors to grep—excuse me,
ripgrep—for that.)
Also, don't make this preëmpt the existing probe-for-return-type suggestions,
despite their being looked unfavorably upon, at least in this situation
(https://github.com/rust-lang/rust/issues/42764#issuecomment-311388958): Cody
Schafer pointed out that that's a separate issue
(https://github.com/rust-lang/rust/pull/43178#issuecomment-314953229).
This is in the matter of #42764.
`rustc_on_unimplemented` supports referring to trait
Add support to `rustc_on_unimplemented` to reference the full path of
the annotated trait. For the following code:
```rust
pub mod Bar {
#[rustc_on_unimplemented = "test error `{Self}` with `{Bar}` `{Baz}` `{Quux}` in `{Foo}`"]
pub trait Foo<Bar, Baz, Quux> {}
}
```
the error message will be:
```
test error `std::string::String` with `u8` `_` `u32` in `Bar::Foo`
```
Fold E0612, E0613 into E0609
As discussed in #42945, with PR 1506 tuple indices are no longer considered a separate case from normal field. This PR folds E06012 ("tuple index out of bounds") and E0613 ("type is not a tuple") into E0609 ("type does not have field with that name")
Resolves#42945
