The assertion in `assert-long-condition.rs` used to be fail like this, all on
one line:
```
thread 'main' panicked at 'assertion failed: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18\n + 19 + 20 + 21 + 22 + 23 + 24 + 25 == 0', tests/ui/macros/assert-long-condition.rs:7:5
```
The `\n` and subsequent indent is because the condition is pretty-printed, and
the pretty-printer inserts a newline. Printing the newline in this way is
arguably reasonable given that the message appears within single quotes, which
is very similar to a string literal.
However, after the assertion printing improvements that were released in 1.73,
the assertion now fails like this:
```
thread 'main' panicked at tests/ui/macros/assert-long-condition.rs:7:5:
assertion failed: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18\n + 19 + 20 + 21 + 22 + 23 + 24 + 25 == 0
```
Now that there are no single quotes around the pretty-printed condition, the
`\n` is quite strange.
This commit gets rid of the `\n`, by removing the `escape_debug` done on the
pretty-printed message. This results in the following:
```
thread 'main' panicked at tests/ui/macros/assert-long-condition.rs:7:5:
assertion failed: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18
+ 19 + 20 + 21 + 22 + 23 + 24 + 25 == 0
```
The overly-large indent is still strange, but that's a separate pretty-printing issue.
This change helps with #108341.
Properly export function defined in test which uses global_asm!()
Currently the test passes with the LLVM backend as the codegen unit partitioning logic happens to place both the global_asm!() and the function which calls the function defined by the global_asm!() in the same CGU. With the Cranelift backend it breaks however as it will place all assembly in separate codegen units to be passed to an external linker.
Detect missing `=>` after match guard during parsing
```
error: expected one of `,`, `:`, or `}`, found `.`
--> $DIR/missing-fat-arrow.rs:25:14
|
LL | Some(a) if a.value == b {
| - while parsing this struct
LL | a.value = 1;
| -^ expected one of `,`, `:`, or `}`
| |
| while parsing this struct field
|
help: try naming a field
|
LL | a: a.value = 1;
| ++
help: you might have meant to start a match arm after the match guard
|
LL | Some(a) if a.value == b => {
| ++
```
Fix#78585.
Show more information when multiple `impl`s apply
- When there are `impl`s without type params, show only those (to avoid showing overly generic `impl`s).
```
error[E0283]: type annotations needed
--> $DIR/multiple-impl-apply.rs:34:9
|
LL | let y = x.into();
| ^ ---- type must be known at this point
|
note: multiple `impl`s satisfying `_: From<Baz>` found
--> $DIR/multiple-impl-apply.rs:14:1
|
LL | impl From<Baz> for Bar {
| ^^^^^^^^^^^^^^^^^^^^^^
...
LL | impl From<Baz> for Foo {
| ^^^^^^^^^^^^^^^^^^^^^^
= note: required for `Baz` to implement `Into<_>`
help: consider giving `y` an explicit type
|
LL | let y: /* Type */ = x.into();
| ++++++++++++
```
- Lower the importance of `T: Sized`, `T: WellFormed` and coercion errors, to prioritize more relevant errors. The pre-existing deduplication logic deals with hiding redundant errors better that way, and we show errors with more metadata that is useful to the user.
- Show `<SelfTy as Trait>::assoc_fn` suggestion in more cases.
```
error[E0790]: cannot call associated function on trait without specifying the corresponding `impl` type
--> $DIR/cross-return-site-inference.rs:38:16
|
LL | return Err(From::from("foo"));
| ^^^^^^^^^^ cannot call associated function of trait
|
help: use a fully-qualified path to a specific available implementation
|
LL | return Err(</* self type */ as From>::from("foo"));
| +++++++++++++++++++ +
```
Fix#88284.
Clarify `invalid_reference_casting` lint around interior mutable types
This is PR intends to clarify the `invalid_reference_casting` lint around interior mutable types by adding a note for them saying that they should go through `UnsafeCell::get`.
So for this code:
```rust
let cell = &std::cell::UnsafeCell::new(0);
let _num = &mut *(cell as *const _ as *mut i32);
```
the following note will be added to the lint output:
```diff
error: casting `&T` to `&mut T` is undefined behavior, even if the reference is unused, consider instead using an `UnsafeCell`
--> $DIR/reference_casting.rs:68:16
|
LL | let _num = &mut *(cell as *const _ as *mut i32);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: for more information, visit <https://doc.rust-lang.org/book/ch15-05-interior-mutability.html>
+ = note: even for types with interior mutability, the only legal way to obtain a mutable pointer from a shared reference is through `UnsafeCell::get`
```
Suggestion are welcome around the note contents.
Fixes https://github.com/rust-lang/rust/issues/116410
cc `@RalfJung`
Currently the test passes with the LLVM backend as the codegen unit
partitioning logic happens to place both the global_asm!() and the
function which calls the function defined by the global_asm!() in the
same CGU. With the Cranelift backend it breaks however as it will place
all assembly in separate codegen units to be passed to an external
linker.
Add a note to duplicate diagnostics
Helps explain why there may be a difference between manual testing and the test suite output and highlights them as something to potentially look into
For existing duplicate diagnostics I just blessed them other than a few files that had other `NOTE` annotations in
Diagnostics: Be more careful when suggesting struct fields
Consolidate the various places which filter out struct fields that shouldn't be suggested into a single function.
Previously, each of those code paths had slightly different and incomplete metrics for no good reason. Now, there's only a single 'complete' metric (namely `is_field_suggestable`) which also filters out hygienic fields that come from different syntax contexts.
Fixes#116334.
More accurately point to where default return type should go
When getting the "default return type" span, instead of pointing to the low span of the next token, point to the high span of the previous token. This:
1. Makes forming return type suggestions more uniform, since we expect them all in the same place.
2. Arguably makes labels easier to understand, since we're pointing to where the implicit `-> ()` would've gone, rather than the starting brace or the semicolon.
r? ```@estebank```
In `report_fullfillment_errors` push back `T: Sized`, `T: WellFormed`
and coercion errors to the end of the list. The pre-existing
deduplication logic eliminates redundant errors better that way, keeping
the resulting output with fewer errors than before, while also having
more detail.
```
error: expected one of `,`, `:`, or `}`, found `.`
--> $DIR/missing-fat-arrow.rs:25:14
|
LL | Some(a) if a.value == b {
| - while parsing this struct
LL | a.value = 1;
| -^ expected one of `,`, `:`, or `}`
| |
| while parsing this struct field
|
help: try naming a field
|
LL | a: a.value = 1;
| ++
help: you might have meant to start a match arm after the match guard
|
LL | Some(a) if a.value == b => {
| ++
```
Fix#78585.
non_lifetime_binders: fix ICE in lint opaque-hidden-inferred-bound
Opaque types like `impl for<T> Trait<T>` would previously lead to an ICE.
r? `@compiler-errors`
Suggest `pin!()` instead of `Pin::new()` when appropriate
When encountering a type that needs to be pinned but that is `!Unpin`, suggest using the `pin!()` macro.
Fix#57994.
Don't suggest nonsense suggestions for unconstrained type vars in `note_source_of_type_mismatch_constraint`
The way we do type inference for suggestions in `note_source_of_type_mismatch_constraint` is a bit strange. We compute the "ideal" method signature, which takes the receiver that we *want* and uses it to compute the types of the arguments that would have given us that receiver via type inference, and use *that* to suggest how to change an argument to make sure our receiver type is inferred correctly.
The problem is that sometimes we have totally unconstrained arguments (well, they're constrained by things outside of the type checker per se, like associated types), and therefore type suggestions are happy to coerce anything to that unconstrained argument. This leads to bogus suggestions, like #116155. This is partly due to above, and partly due to the fact that `emit_type_mismatch_suggestions` doesn't double check that its suggestions are actually compatible with the program other than trying to satisfy the type mismatch.
This adds a hack to make sure that at least the types are fully constrained, but I guess I could also rip out this logic altogether. There would be some sad diagnostics regressions though, such as `tests/ui/type/type-check/point-at-inference-4.rs`.
Fixes#116155
We're stabilizing `async fn` in trait (AFIT), but we have some
reservations about how people might use this in the definitions of
publicly-visible traits, so we're going to lint about that.
This is a bit of an odd lint for `rustc`. We normally don't lint just
to have people confirm that they understand how Rust works. But in
this one exceptional case, this seems like the right thing to do as
compared to the other plausible alternatives.
In this commit, we describe the nature of this odd lint.