If an error message is emitted that spans several files, only the
primary file currently has line and column data attached. This is
useful information, even in files other than the one in which the error
occurs. We can often work out which line and column the error
corresponds to in other files — in this case it is helpful to add them
(in the case of ambiguity, the first relevant line/column is picked,
which is still helpful than none).
do not ICE when return type includes unconstrained anon region
It turns out that this *can* happen after all, if the region is only
used in projections from the input types.
Fixes https://github.com/rust-lang/rust/issues/47511
r? @eddyb
Fix spans in unused import lint for nested groups
This fixes an inconsistency for empty nested groups, and adds a test for all the possible cases of the lint.
```
warning: unused imports: `*`, `Foo`, `baz::{}`, `foobar::*`
--> test.rs:16:11
|
16 | use foo::{Foo, bar::{baz::{}, foobar::*}, *};
| ^^^ ^^^^^^^ ^^^^^^^^^ ^
|
= note: #[warn(unused_imports)] on by default
warning: unused import: `*`
--> test.rs:17:24
|
17 | use foo::bar::baz::{*, *};
| ^
warning: unused import: `use foo::{};`
--> test.rs:18:1
|
18 | use foo::{};
| ^^^^^^^^^^^^
```
cc #44494
Fix into() cast paren check precedence
As discussed in #47699 the logic for determining if an expression needs parenthesis when suggesting an `.into()` cast is incorrect. Two broken examples from nightly are:
```
error[E0308]: mismatched types
--> main.rs:4:10
|
4 | test(foo as i8);
| ^^^^^^^^^ expected i32, found i8
help: you can cast an `i8` to `i32`, which will sign-extend the source value
|
4 | test(foo as i8.into());
|
```
```
error[E0308]: mismatched types
--> main.rs:4:10
|
4 | test(*foo);
| ^^^^ expected i32, found i8
help: you can cast an `i8` to `i32`, which will sign-extend the source value
|
4 | test(*foo.into());
|
```
As suggested by @petrochenkov switch the precedence check to `PREC_POSTFIX`. This catches both `as` and unary operators. Fixes#47699.
r? @petrochenkov
On missing method do not suggest private traits
When encountering a method call for an ADT that doesn't have any
implementation of it, we search for traits that could be implemented
that do have that method. Filter out private non-local traits that would
not be able to be implemented.
This doesn't account for public traits that are in a private scope, but
works as a first approximation and is a more correct behavior than the
current one.
Fix#45781.
As discussed in #47699 the logic for determining if an expression needs
parenthesis when suggesting an `.into()` cast is incorrect. Two broken
examples from nightly are:
```
error[E0308]: mismatched types
--> main.rs:4:10
|
4 | test(foo as i8);
| ^^^^^^^^^ expected i32, found i8
help: you can cast an `i8` to `i32`, which will sign-extend the source value
|
4 | test(foo as i8.into());
|
```
```
error[E0308]: mismatched types
--> main.rs:4:10
|
4 | test(*foo);
| ^^^^ expected i32, found i8
help: you can cast an `i8` to `i32`, which will sign-extend the source value
|
4 | test(*foo.into());
|
```
As suggested by @petrochenkov switch the precedence check to
PREC_POSTFIX. This catches both `as` and unary operators. Fixes#47699.
When E0277's span points at a `for` loop, the actual issue is in the
element being iterated. Instead of pointing at the entire loop, point
only at the first line (when possible) so that the span ends in the
element for which E0277 was triggered.
Immovable generators
This adds support for immovable generators which allow you to borrow local values inside generator across suspension points. These are declared using a `static` keyword:
```rust
let mut generator = static || {
let local = &Vec::new();
yield;
local.push(0i8);
};
generator.resume();
// ERROR moving the generator after it has resumed would invalidate the interior reference
// drop(generator);
```
Region inference is no longer affected by the types stored in generators so the regions inside should be similar to other code (and unaffected by the presence of `yield` expressions). The borrow checker is extended to pick up the slack so interior references still result in errors for movable generators. This fixes#44197, #45259 and #45093.
This PR depends on [PR #44917 (immovable types)](https://github.com/rust-lang/rust/pull/44917), I suggest potential reviewers ignore the first commit as it adds immovable types.
When encountering a method call for an ADT that doesn't have any
implementation of it, we search for traits that could be implemented
that do have that method. Filter out private non-local traits that would
not be able to be implemented.
This doesn't account for public traits that are in a private scope, but
works as a first approximation and is a more correct behavior than the
current one.
renumber regions in generators
This fixes#47189, but I think we still have to double check various things around how to treat generators in MIR type check + borrow check (e.g., what borrows should be invalidated by a `Suspend`? What consistency properties should type check be enforcing anyway around the "interior" type?)
Also fixes#47587 thanks to @spastorino's commit.
r? @pnkfelix
Implement repr(transparent)
r? @eddyb for the functional changes. The bulk of the PR is error messages and docs, might be good to have a doc person look over those.
cc #43036
cc @nox
Custom error when moving arg outside of its closure
When given the following code:
```rust
fn give_any<F: for<'r> FnOnce(&'r ())>(f: F) {
f(&());
}
fn main() {
let mut x = None;
give_any(|y| x = Some(y));
}
```
provide a custom error:
```
error: borrowed data cannot be moved outside of its closure
--> file.rs:7:27
|
6 | let mut x = None;
| ----- borrowed data cannot be moved into here...
7 | give_any(|y| x = Some(y));
| --- ^ cannot be moved outside of its closure
| |
| ...because it cannot outlive this closure
```
instead of the generic lifetime error:
```
error[E0495]: cannot infer an appropriate lifetime due to conflicting requirements
--> file.rs:7:27
|
7 | give_any(|y| x = Some(y));
| ^
|
note: first, the lifetime cannot outlive the anonymous lifetime #2 defined on the body at 7:14...
--> file.rs:7:14
|
7 | give_any(|y| x = Some(y));
| ^^^^^^^^^^^^^^^
note: ...so that expression is assignable (expected &(), found &())
--> file.rs:7:27
|
7 | give_any(|y| x = Some(y));
| ^
note: but, the lifetime must be valid for the block suffix following statement 0 at 6:5...
--> file.rs:6:5
|
6 | / let mut x = None;
7 | | give_any(|y| x = Some(y));
8 | | }
| |_^
note: ...so that variable is valid at time of its declaration
--> file.rs:6:9
|
6 | let mut x = None;
| ^^^^^
```
Fix#45983.
Tweaks to invalid ctor messages
- Do not suggest using a constructor that isn't accessible
- Suggest the appropriate syntax (`()`/`{}` as appropriate)
- Add note when trying to use `Self` as a ctor
CC #22488, fix#47085.
Closure argument mismatch tweaks
- use consistent phrasing for expected and found arguments
- suggest changing arguments to tuple if possible
- suggest changing single tuple argument to arguments if possible
Fix#44150.
- use consistent phrasing for expected and found arguments
- suggest changing arugments to tuple if possible
- suggest changing single tuple argument to arguments if possible
On E0283, point at method with the requirements
On required type annotation diagnostic error, point at method with the
requirements if the span is available.
CC #45453.
