Make "missing field" error message more natural
```rust
struct A {
x: i32,
y: i32,
z: i32,
}
fn main() {
A { };
}
```
```
error[E0063]: missing fields `x`, `y`, `z` in initializer of `A`
--> src/main.rs:8:5
|
8 | A { };
| ^ missing `x`, `y`, `z`
```
This error is now:
```
error[E0063]: missing fields `x`, `y` and `z` in initializer of `A`
--> src/main.rs:8:5
|
8 | A { };
| ^ missing `x`, `y` and `z`
```
I thought it looked nicer and more natural this way. Also, if there is >3 fields missing, there is an "and" as well ("missing \`x\`, \`y\`, \`z\` *and* 1 other field"), but for <=3 there is not. As such it improves consistency too.
As for the implementation, originally I ended up with a chunky `push_str` algorithm but then I figured I could just do the formatting manually since it's just 3 field names at maximum. It is comparatively readable.
As a sidenote, one thing I was wondering about is, isn't there more cases where you have a list of things like field names? Maybe this whole thing can at some point later be made into a more general function to be used in multiple areas.
[intra-doc links] Don't check feature gates of items re-exported across crates
It should be never break another crate to re-export a public item.
Note that this doesn't check the feature gate at
*all* for other crates:
- Feature-gates aren't currently serialized, so the only way to check
the gate is with ad-hoc attribute checking.
- Checking the feature gate twice (once when documenting the original
crate and one when documenting the current crate) seems not great.
This should still catch using the feature most of the time though, since
people tend to document their own crates.
Closes https://github.com/rust-lang/rust/issues/82284.
r? `@Manishearth`
Rollup of 11 pull requests
Successful merges:
- #81300 (BTree: share panicky test code & test panic during clear, clone)
- #81706 (Document BinaryHeap unsafe functions)
- #81833 (parallelize x.py test tidy)
- #81966 (Add new `rustc` target for Arm64 machines that can target the iphonesimulator)
- #82154 (Update RELEASES.md 1.50 to include methods stabilized in #79342)
- #82177 (Do not delete bootstrap.exe on Windows during clean)
- #82181 (Add check for ES5 in CI)
- #82229 (Add [A-diagnostics] bug report template)
- #82233 (try-back-block-type test: Use TryFromSliceError for From test)
- #82302 (Remove unsafe impl Send for CompletedTest & TestResult)
- #82349 (test: Print test name only once on timeout)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
try-back-block-type test: Use TryFromSliceError for From test
Using `i32` is rather fragile because it has many implementations. Recently in an early draft of another MR (#82228) I did something that introduced a new `i32 as From<something>` impl and this test broke.
TryFromSliceError is nice because it doesn't seem likely to grow new conversions. We still have one conversion, from Infallible.
My other MR is going to be reworked and won't need this any more but having done it I thought I would submit it rather than just throw it away. Sorry for the tiny MR.
Improve assert_eq! and assert_ne!
This PR improves `assert_eq!` and `assert_ne!` by moving the panicking code in an external function.
It does not change the fast path, but the move of the formatting in the cold path (the panic) may have a positive effect on in instruction cache use and with inlining.
Moreover, the use of trait objects instead of generic may improve compile times for `assert_eq!`-heavy code.
Godbolt link: ~~https://rust.godbolt.org/z/TYa9MT~~ \
Updated: https://rust.godbolt.org/z/bzE84x
Don't generate src link on dummy spans
Just realized that the "auto trait impls" had `[src]` links were leading to the crate root because they were dummy spans. This PR fixes this issue.
cc `@jyn514`
r? `@camelid`
Fix panic in 'remove semicolon' when types are not local
It's not possible to check if removing a semicolon fixes the type error
when checking match arms and one or both of the last arm's and the
current arm's return types are imported "opaque" types. In these cases
we don't generate a "consider removing semicolon" suggestions.
Fixes#81839
---
I'm not sure how to add a test for this. I think the test would need at least two crates. Do we have any existing tests that do this so that I can take a look?
It should be never break another crate to re-export a public item.
Note that this doesn't check the feature gate at
*all* for other crates:
- Feature-gates aren't currently serialized, so the only way to check
the gate is with ad-hoc attribute checking.
- Checking the feature gate twice (once when documenting the original
crate and one when documenting the current crate) seems not great.
This should still catch using the feature most of the time though, since
people tend to document their own crates.
rustdoc: Support argument files
Factors out the `rustc_driver` logic that handles argument files so that rustdoc supports them as well, e.g.:
rustdoc `@argfile`
This is needed to be able to generate docs for projects that already use argument files when compiling them, e.g. projects that pass a huge number of `--cfg` arguments.
The feature was stabilized for `rustc` in #66172.
Do not ICE when evaluating locals' types of invalid `yield`
When a `yield` is outside of a generator, check its value regardless to
avoid an ICE while trying to get all locals' types in writeback.
Fix#78653.
ast: Keep expansion status for out-of-line module items
I.e. whether a module `mod foo;` is already loaded from a file or not.
This is a pre-requisite to correctly treating inner attributes on such modules (https://github.com/rust-lang/rust/issues/81661).
With this change AST structures for `mod` items diverge even more for AST structure for the crate root, which previously used `ast::Mod`.
Therefore this PR removes `ast::Mod` from `ast::Crate` in the first commit, these two things are sufficiently different from each other, at least at syntactic level.
Customization points for visiting a "`mod` item or crate root" were also removed from AST visitors (`fn visit_mod`).
`ast::Mod` itself was refactored away in the second commit in favor of `ItemKind::Mod(Unsafe, ModKind)`.
name async generators something more human friendly in type error diagnostic
fixes#81457
Some details:
1. I opted to load the generator kind from the hir in TyCategory. I also use 1 impl in the hir for the descr
2. I named both the source of the future, in addition to the general type (`future`), not sure what is preferred
3. I am not sure what is required to make sure "generator" is not referred to anywhere. A brief `rg "\"generator\"" showed me that most diagnostics correctly distinguish from generators and async generator, but the `descr` of `DefKind` is pretty general (not sure how thats used)
4. should the descr impl of AsyncGeneratorKind use its display impl instead of copying the string?
Factors out the `rustc_driver` logic that handles argument files
so that rustdoc supports them as well, e.g.:
rustdoc @argfile
This is needed to be able to generate docs for projects that
already use argument files when compiling them, e.g. projects
that pass a huge number of `--cfg` arguments.
The feature was stabilized for `rustc` in #66172.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Replace if-let and while-let with `if let` and `while let`
This pull request replaces if-let and while-let with `if let` and `while let`.
closes https://github.com/rust-lang/rust/issues/82205
const_generics: Dont evaluate array length const when handling yet another error
Same ICE as #82009 except triggered by a different error.
cc ``@lcnr``
r? ``@varkor``
Ensure valid TraitRefs are created for GATs
This fixes `ProjectionTy::trait_ref` to use the correct substs. Places that need all of the substs have been updated to not use `trait_ref`.
r? ````@jackh726````
[libtest] Run the test synchronously when hitting thread limit
libtest currently panics if it hits the thread limit. This often results in spurious test failures (<code>thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 11, kind: WouldBlock, message: "Resource temporarily unavailable" }'</code> ... `error: test failed, to rerun pass '--lib'`). This PR makes it continue to run the test synchronously if it runs out of threads.
Closes#78165.
``@rustbot`` label: A-libtest T-libs
Crate root is sufficiently different from `mod` items, at least at syntactic level.
Also remove customization point for "`mod` item or crate root" from AST visitors.
Add diagnostics for specific cases for const/type mismatch err
For now, this adds at least more information so better diagnostics can be emitted for const mismatch errors.
I'm not sure what exactly we want to emit, so I've left notes there temporarily, also to see if this is the right approach
r? ```@lcnr```
cc: ```@estebank```
Implement RFC 2580: Pointer metadata & VTable
RFC: https://github.com/rust-lang/rfcs/pull/2580
~~Before merging this PR:~~
* [x] Wait for the end of the RFC’s [FCP to merge](https://github.com/rust-lang/rfcs/pull/2580#issuecomment-759145278).
* [x] Open a tracking issue: https://github.com/rust-lang/rust/issues/81513
* [x] Update `#[unstable]` attributes in the PR with the tracking issue number
----
This PR extends the language with a new lang item for the `Pointee` trait which is special-cased in trait resolution to implement it for all types. Even in generic contexts, parameters can be assumed to implement it without a corresponding bound.
For this I mostly imitated what the compiler was already doing for the `DiscriminantKind` trait. I’m very unfamiliar with compiler internals, so careful review is appreciated.
This PR also extends the standard library with new unstable APIs in `core::ptr` and `std::ptr`:
```rust
pub trait Pointee {
/// One of `()`, `usize`, or `DynMetadata<dyn SomeTrait>`
type Metadata: Copy + Send + Sync + Ord + Hash + Unpin;
}
pub trait Thin = Pointee<Metadata = ()>;
pub const fn metadata<T: ?Sized>(ptr: *const T) -> <T as Pointee>::Metadata {}
pub const fn from_raw_parts<T: ?Sized>(*const (), <T as Pointee>::Metadata) -> *const T {}
pub const fn from_raw_parts_mut<T: ?Sized>(*mut (),<T as Pointee>::Metadata) -> *mut T {}
impl<T: ?Sized> NonNull<T> {
pub const fn from_raw_parts(NonNull<()>, <T as Pointee>::Metadata) -> NonNull<T> {}
/// Convenience for `(ptr.cast(), metadata(ptr))`
pub const fn to_raw_parts(self) -> (NonNull<()>, <T as Pointee>::Metadata) {}
}
impl<T: ?Sized> *const T {
pub const fn to_raw_parts(self) -> (*const (), <T as Pointee>::Metadata) {}
}
impl<T: ?Sized> *mut T {
pub const fn to_raw_parts(self) -> (*mut (), <T as Pointee>::Metadata) {}
}
/// `<dyn SomeTrait as Pointee>::Metadata == DynMetadata<dyn SomeTrait>`
pub struct DynMetadata<Dyn: ?Sized> {
// Private pointer to vtable
}
impl<Dyn: ?Sized> DynMetadata<Dyn> {
pub fn size_of(self) -> usize {}
pub fn align_of(self) -> usize {}
pub fn layout(self) -> crate::alloc::Layout {}
}
unsafe impl<Dyn: ?Sized> Send for DynMetadata<Dyn> {}
unsafe impl<Dyn: ?Sized> Sync for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Debug for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Unpin for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Copy for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Clone for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Eq for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> PartialEq for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Ord for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> PartialOrd for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Hash for DynMetadata<Dyn> {}
```
API differences from the RFC, in areas noted as unresolved questions in the RFC:
* Module-level functions instead of associated `from_raw_parts` functions on `*const T` and `*mut T`, following the precedent of `null`, `slice_from_raw_parts`, etc.
* Added `to_raw_parts`
Implement reborrow for closure captures
The strategy for captures is detailed here with examples: https://hackmd.io/PzxYMPY4RF-B9iH9uj9GTA
Key points:
- We only need to reborrow a capture in case of move closures.
- If we mutate something via a `&mut` we store it as a `MutBorrow`/`UniqueMuBorrow` of the path containing the `&mut`,
- Similarly, if it's read via `&` ref we just store it as a `ImmBorrow` of the path containing the `&` ref.
- If a path doesn't deref a `&mut`, `&`, then that path is captured by Move.
- If the use of a path results in a move when the closure is called, then that path is truncated before any deref and the truncated path is moved into the closure.
- In the case of non-move closure if a use of a path results in a move, then the path is truncated before any deref and the truncated path is moved into the closure.
Note that the implementation differs a bit from the document to allow for truncated path to be used in the ClosureKind analysis that happens as part of the first capture analysis pass.
Closes: https://github.com/rust-lang/project-rfc-2229/issues/31
r? ````@nikomatsakis````
Placeholder lifetime error cleanup
- Remove note of trait definition
- Avoid repeating the same self type
- Use original region names when possible
- Use this error kind more often
- Print closure signatures when they are suppose to implement `Fn*` traits
Works towards #57374
r? ```@nikomatsakis```
Fix SourceMap::start_point
`start_point` needs to return the *first* character's span, but it would
previously call `find_width_of_character_at_span` which returns the span
of the *last* character. The implementation is now fixed.
Other changes:
- Docs for start_point, end_point, find_width_of_character_at_span
updated
- Minor simplification in find_width_of_character_at_span code
Fixes#81800
Document that `assert!` format arguments are evaluated lazily
It can be useful to do some computation in `assert!` format arguments, in order to get better error messages. For example:
```rust
assert!(
some_condition,
"The state is invalid. Details: {}",
expensive_call_to_get_debugging_info(),
);
```
It seems like `assert!` only evaluates the format arguments if the assertion fails, which is useful but doesn't appear to be documented anywhere. This PR documents the behavior and adds some tests.
Don't fail to remove files if they are missing
In the backend we may want to remove certain temporary files, but in
certain other situations these files might not be produced in the first
place. We don't exactly care about that, and the intent is really that
these files are gone after a certain point in the backend.
Here we unify the backend file removing calls to use `ensure_removed`
which will attempt to delete a file, but will not fail if it does not
exist (anymore).
The tradeoff to this approach is, of course, that we may miss instances
were we are attempting to remove files at wrong paths due to some bug –
compilation would silently succeed but the temporary files would remain
there somewhere.
