When there're more than one suggestions in the same diagnostic, they are
displayed in their own block, instead of inline. In order to reduce
confusion, those blocks now display the line number.
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`
```
Prior to this PR, when we aborted because a "critical pass" failed, we
displayed the number of errors from that critical pass. While that's the
number of errors that caused compilation to abort in *that place*,
that's not what people really want to know. Instead, always report the
total number of errors, and don't bother to track the number of errors
from the last pass that failed.
This changes the compiler driver API to handle errors more smoothly,
and therefore is a compiler-api-[breaking-change].
Fixes#42793.
Adding diagnostic code 0611 for lifetime errors with one named, one anonymous lifetime parameter
This is a fix for #42517
Note that this only handles the above case for **function declarations** and **traits**.
`impl items` and `closures` will be handled in a later PR.
Example
```
fn foo<'a>(x: &i32, y: &'a i32) -> &'a i32 {
if x > y { x } else { y }
}
```
now displays the following error message. ui tests have been added for the same.
```
error[E0611]: explicit lifetime required in the type of `x`
11 | fn foo<'a>(x: &i32, y: &'a i32) -> &'a i32 {
| ^ consider changing the type of `x` to `&'a i32`
12 | if x > y { x } else { y }
| - lifetime `'a` required
```
#42516
r? @nikomatsakis
Coerce fields to the expected field type
Fully fixes#31260.
This needs a crater run. I was supposed to do this last month but it slipped. Let's get this done.
Detect missing `;` on methods with return type `()`
- Point out the origin of a type requirement when it is the return type
of a method
- Point out possibly missing semicolon when the return type is `()` and
the implicit return makes sense as a statement
- Suggest changing the return type of methods with default return type
- Don't suggest changing the return type on `fn main()`
- Don't suggest changing the return type on impl fn
- Suggest removal of semicolon (instead of being help)
only set "overruled by outer forbid" once for lint groups, by group name
Previously, conflicting forbid/allow attributes for a lint group would
result in a separate "allow(L) overruled by outer forbid(L)" error for
every lint L in the group. This was needlessly and annoyingly verbose;
we prefer to just have one error pointing out the conflicting
attributes.
(Also, while we're touching context.rs, clean up some unused arguments.)
Resolves#42873.
- Point out the origin of a type requirement when it is the return type
of a method
- Point out possibly missing semicolon when the return type is () and
the implicit return makes sense as a statement
- Suggest changing the return type of methods with default return type
- Don't suggest changing the return type on fn main()
- Don't suggest changing the return type on impl fn
Previously, conflicting forbid/allow attributes for a lint group would
result in a separate "allow(L) overruled by outer forbid(L)" error for
every lint L in the group. This was needlessly and annoyingly verbose;
we prefer to just have one error pointing out the conflicting
attributes.
Resolves#42873.
Print the two types in the span label for transmute errors.
Fixes#37157. I'm not entirely happy with the changes here but overall it's better in my opinion; we certainly avoid the odd language in that issue, which changes to:
```
error[E0512]: transmute called with differently sized types: <C as TypeConstructor<'a>>::T (size can vary because of <C as TypeConstructor>::T) to <C as TypeConstructor<'b>>::T (size can vary because of <C as TypeConstructor>::T)
--> test.rs:8:5
|
8 | ::std::mem::transmute(x)
| ^^^^^^^^^^^^^^^^^^^^^ transmuting between <C as TypeConstructor<'a>>::T and <C as TypeConstructor<'b>>::T
error: aborting due to previous error(s)
```
Implement lazy loading of external crates' sources. Fixes#38875Fixes#38875. This is a follow-up to #42507. When a (now correctly translated) span from an external crate is referenced in a error, warning or info message, we still don't have the source code being referenced.
Since stuffing the source in the serialized metadata of an rlib is extremely wasteful, the following scheme has been implemented:
* File maps now contain a source hash that gets serialized as well.
* When a span is rendered in a message, the source hash in the corresponding file map(s) is used to try and load the source from the corresponding file on disk. If the file is not found or the hashes don't match, the failed attempt is recorded (and not retried).
* The machinery fetching source lines from file maps is augmented to use the lazily loaded external source as a secondary fallback for file maps belonging to external crates.
This required a small change to the expected stderr of one UI test (it now renders a span, where previously was none).
Further work can be done based on this - some of the machinery previously used to hide external spans is possibly obsolete and the hashing code can be reused in different places as well.
r? @eddyb
Report error for assignment in `if` condition
For code like `if x = 3 {}`, output:
```
error[E0308]: mismatched types
--> $DIR/issue-17283.rs:25:8
|
25 | if x = x {
| ^^^^^
| |
| help: did you mean to compare equality? `x == x`
| expected bool, found ()
|
= note: expected type `bool`
found type `()`
```
Fix#40926.
