Look at the expression that was parsed when trying to recover from a bad `if` condition to determine what was likely intended by the user beyond "maybe this was meant to be an `else` body".
```
error: expected `{`, found `map`
--> $DIR/missing-dot-on-if-condition-expression-fixable.rs:4:30
|
LL | for _ in [1, 2, 3].iter()map(|x| x) {}
| ^^^ expected `{`
|
help: you might have meant to write a method call
|
LL | for _ in [1, 2, 3].iter().map(|x| x) {}
| +
```
This is consistent with all other diagnostics I could find containing
features and enables the use of `DiagSymbolList` for generalizing
diagnostics for unstable library features to multiple features.
When a trait is not implemented for a type, but there *is* an `impl`
for another type or different trait params, we format the output to
use highlighting in the same way that E0308 does for types.
The logic accounts for 3 cases:
- When both the type and trait in the expected predicate and the candidate are different
- When only the types are different
- When only the trait generic params are different
For each case, we use slightly different formatting and wording.
Remove the "which is required by `{root_obligation}`" post-script in
"the trait `X` is not implemented for `Y`" explanation in E0277. This
information is already conveyed in the notes explaining requirements,
making it redundant while making the text (particularly in labels)
harder to read.
```
error[E0277]: the trait bound `NotCopy: Copy` is not satisfied
--> $DIR/wf-static-type.rs:10:13
|
LL | static FOO: IsCopy<Option<NotCopy>> = IsCopy { t: None };
| ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopy`
|
= note: required for `Option<NotCopy>` to implement `Copy`
note: required by a bound in `IsCopy`
--> $DIR/wf-static-type.rs:7:17
|
LL | struct IsCopy<T:Copy> { t: T }
| ^^^^ required by this bound in `IsCopy`
```
vs the prior
```
error[E0277]: the trait bound `NotCopy: Copy` is not satisfied
--> $DIR/wf-static-type.rs:10:13
|
LL | static FOO: IsCopy<Option<NotCopy>> = IsCopy { t: None };
| ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopy`, which is required by `Option<NotCopy>: Copy`
|
= note: required for `Option<NotCopy>` to implement `Copy`
note: required by a bound in `IsCopy`
--> $DIR/wf-static-type.rs:7:17
|
LL | struct IsCopy<T:Copy> { t: T }
| ^^^^ required by this bound in `IsCopy`
```
Stop inverting expectation in normalization errors
We have some funky special case logic to invert the expectation and actual type for normalization errors depending on their cause code. IMO most of the error messages get better, except for `try {}` blocks' type expectations. I think that these need to be special cased in some other way, rather than via this hack.
Fixes#131763
To fix the linker errors, we need to set the output extension to `.js` instead
of `.wasm`. Setting the output to a `.wasm` file puts Emscripten into standalone
mode which is effectively a distinct target. We need to set the runner to be
`node` as well.
This fixes most of the ui tests. I fixed a few more tests with simple problems:
- `intrinsics/intrinsic-alignment.rs` and `structs-enums/rec-align-u64.rs` --
Two `#[cfg]` macros match for Emscripten so we got a duplicate definition of
`mod m`.
- `issues/issue-12699.rs` -- Seems to hang so I disabled it
- `process/process-sigpipe.rs` -- Not expected to work on Emscripten so I
disabled it
Compiler & its UI tests: Rename remaining occurrences of "object safe" to "dyn compatible"
Follow-up to #130826.
Part of #130852.
1. 1st commit: Fix stupid oversights. Should've been part of #130826.
2. 2nd commit: Rename the unstable feature `object_safe_for_dispatch` to `dyn_compatible_for_dispatch`. Might not be worth the churn, you decide.
3. 3rd commit: Apply the renaming to all UI tests (contents and paths).
Instead of
```
error[E0277]: the size for values of type `(dyn ThriftService<(), AssocType = _> + 'static)` cannot be known at compilation time
--> $DIR/issue-59324.rs:23:20
|
LL | fn with_factory<H>(factory: dyn ThriftService<()>) {}
| ^^^^^^^ doesn't have a size known at compile-time
```
output
```
error[E0277]: the size for values of type `(dyn ThriftService<(), AssocType = _> + 'static)` cannot be known at compilation time
--> $DIR/issue-59324.rs:23:29
|
LL | fn with_factory<H>(factory: dyn ThriftService<()>) {}
| ^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
```
Suggest the correct pattern syntax on usage of unit variant pattern for a struct variant
Closes#126243
I add a suggestion on usage of unit variant pattern for a struct variant.
Detect `*` operator on `!Sized` expression
The suggestion is new:
```
error[E0277]: the size for values of type `str` cannot be known at compilation time
--> $DIR/unsized-str-in-return-expr-arg-and-local.rs:15:9
|
LL | let x = *"";
| ^ doesn't have a size known at compile-time
|
= help: the trait `Sized` is not implemented for `str`
= note: all local variables must have a statically known size
= help: unsized locals are gated as an unstable feature
help: references to `!Sized` types like `&str` are `Sized`; consider not dereferencing the expression
|
LL - let x = *"";
LL + let x = "";
|
```
Fix#128199.
bump conflicting_repr_hints lint to be shown in dependencies
This has been a future compatibility lint for years, let's bump it up to be shown in dependencies (so that hopefully we can then make it a hard error fairly soon).
Cc https://github.com/rust-lang/rust/issues/68585
```
error[E0277]: the size for values of type `str` cannot be known at compilation time
--> $DIR/unsized-str-in-return-expr-arg-and-local.rs:15:9
|
LL | let x = *"";
| ^ doesn't have a size known at compile-time
|
= help: the trait `Sized` is not implemented for `str`
= note: all local variables must have a statically known size
= help: unsized locals are gated as an unstable feature
help: references are always `Sized`, even if they point to unsized data; consider not dereferencing the expression
|
LL - let x = *"";
LL + let x = "";
|
```
Rustc of course already WF-checked the field types at the definition
site, but for error tainting of consts to work properly, there needs to
be an error emitted at the use site. Previously, with no use-site error,
we proceeded with CTFE and ran into ICEs since we are running code with
type errors.
Emitting use-site errors also brings struct-like constructors more in
line with fn-like constructors since they already emit use-site errors
for WF issues.
turn `invalid_type_param_default` into a `FutureReleaseErrorReportInDeps`
`````@rust-lang/types````` I assume the plan is still to disallow this? It has been a future-compat lint for a long time, seems ripe to go for hard error.
However, turns out that outright removing it right now would lead to [tons of crater regressions](https://github.com/rust-lang/rust/pull/127655#issuecomment-2228285460), so for now this PR just makes this future-compat lint show up in cargo's reports, so people are warned when they use a dependency that is affected by this.
Fixes https://github.com/rust-lang/rust/issues/27336 by removing the feature gate (so there's no way to silence the lint even on nightly)
CC https://github.com/rust-lang/rust/issues/36887
elaborate unknowable goals
A reimplemented version of #124532 affecting only the new solver. Always trying to prove super traits ends up causing a fatal overflow error in diesel, so we cannot land this in the old solver.
The following test currently does not pass coherence:
```rust
trait Super {}
trait Sub<T>: Super {}
trait Overlap<T> {}
impl<T, U: Sub<T>> Overlap<T> for U {}
impl<T> Overlap<T> for () {}
fn main() {}
```
We check whether `(): Sub<?t>` holds. This stalls with ambiguity as downstream crates may add an impl for `(): Sub<Local>`. However, its super trait bound `(): Super` cannot be implemented downstream, so this one is known not to hold.
By trying to prove that all the super bounds of a trait before adding a coherence unknowable candidate, this compiles. This is necessary to prevent breakage from enabling `-Znext-solver=coherence` (#121848), see tests/ui/coherence/super-traits/super-trait-knowable-2.rs for more details. The idea is that while there may be an impl of the trait itself we don't know about, if we're able to prove that a super trait is definitely not implemented, then that impl would also never apply/not be well-formed.
This approach is different from #124532 as it allows tests/ui/coherence/super-traits/super-trait-knowable-3.rs to compile. The approach in #124532 only elaborating the root obligations while this approach tries it for all unknowable trait goals.
r? `@compiler-errors`
Replace ASCII control chars with Unicode Control Pictures
Replace ASCII control chars like `CR` with Unicode Control Pictures like `␍`:
```
error: bare CR not allowed in doc-comment
--> $DIR/lex-bare-cr-string-literal-doc-comment.rs:3:32
|
LL | /// doc comment with bare CR: '␍'
| ^
```
Centralize the checking of unicode char width for the purposes of CLI display in one place. Account for the new replacements. Remove unneeded tracking of "zero-width" unicode chars, as we calculate these in the `SourceMap` as needed now.
Reorder trait bound modifiers *after* `for<...>` binder in trait bounds
This PR suggests changing the grammar of trait bounds from:
```
[CONSTNESS] [ASYNCNESS] [?] [BINDER] [TRAIT_PATH]
const async ? for<'a> Sized
```
to
```
([BINDER] [CONSTNESS] [ASYNCNESS] | [?]) [TRAIT_PATH]
```
i.e., either
```
? Sized
```
or
```
for<'a> const async Sized
```
(but not both)
### Why?
I think it's strange that the binder applies "more tightly" than the `?` trait polarity. This becomes even weirder when considering that we (or at least, I) want to have `async` trait bounds expressed like:
```
where T: for<'a> async Fn(&'a ()) -> i32,
```
and not:
```
where T: async for<'a> Fn(&'a ()) -> i32,
```
### Fallout
No crates on crater use this syntax, presumably because it's literally useless. This will require modifying the reference grammar, though.
### Alternatives
If this is not desirable, then we can alternatively keep parsing `for<'a>` after the `?` but deprecate it with either an FCW (or an immediate hard error), and begin parsing `for<'a>` *before* the `?`.
When encountering `-> Trait`, suggest `-> Box<dyn Trait>` (instead of `-> Box<Trait>`.
If there's a single returned type within the `fn`, suggest `-> impl Trait`.
Tweak suggestions when using incorrect type of enum literal
More accurate suggestions when writing wrong style of enum variant literal:
```
error[E0533]: expected value, found struct variant `E::Empty3`
--> $DIR/empty-struct-braces-expr.rs:18:14
|
LL | let e3 = E::Empty3;
| ^^^^^^^^^ not a value
|
help: you might have meant to create a new value of the struct
|
LL | let e3 = E::Empty3 {};
| ++
```
```
error[E0533]: expected value, found struct variant `E::V`
--> $DIR/struct-literal-variant-in-if.rs:10:13
|
LL | if x == E::V { field } {}
| ^^^^ not a value
|
help: you might have meant to create a new value of the struct
|
LL | if x == (E::V { field }) {}
| + +
```
```
error[E0618]: expected function, found enum variant `Enum::Unit`
--> $DIR/suggestion-highlights.rs:15:5
|
LL | Unit,
| ---- enum variant `Enum::Unit` defined here
...
LL | Enum::Unit();
| ^^^^^^^^^^--
| |
| call expression requires function
|
help: `Enum::Unit` is a unit enum variant, and does not take parentheses to be constructed
|
LL - Enum::Unit();
LL + Enum::Unit;
|
```
```
error[E0599]: no variant or associated item named `tuple` found for enum `Enum` in the current scope
--> $DIR/suggestion-highlights.rs:36:11
|
LL | enum Enum {
| --------- variant or associated item `tuple` not found for this enum
...
LL | Enum::tuple;
| ^^^^^ variant or associated item not found in `Enum`
|
help: there is a variant with a similar name
|
LL | Enum::Tuple(/* i32 */);
| ~~~~~~~~~~~~~~~~;
|
```
Tweak "field not found" suggestion when giving struct literal for tuple struct type:
```
error[E0560]: struct `S` has no field named `x`
--> $DIR/nested-non-tuple-tuple-struct.rs:8:19
|
LL | pub struct S(f32, f32);
| - `S` defined here
...
LL | let _x = (S { x: 1.0, y: 2.0 }, S { x: 3.0, y: 4.0 });
| ^ field does not exist
|
help: `S` is a tuple struct, use the appropriate syntax
|
LL | let _x = (S(/* f32 */, /* f32 */), S { x: 3.0, y: 4.0 });
| ~~~~~~~~~~~~~~~~~~~~~~~
No longer track "zero-width" chars in `SourceMap`, read directly from the line when calculating the `display_col` of a `BytePos`. Move `char_width` to `rustc_span` and use it from the emitter.
This change allows the following to properly align in terminals (depending on the font, the replaced control codepoints are rendered as 1 or 2 width, on my terminal they are rendered as 1, on VSCode text they are rendered as 2):
```
error: this file contains an unclosed delimiter
--> $DIR/issue-68629.rs:5:17
|
LL | ␜␟ts␀![{i
| -- unclosed delimiter
| |
| unclosed delimiter
LL | ␀␀ fn rݻoa>rݻm
| ^
```
Use a multipart suggestion instead of a single whole-span replacement:
```
error[E0796]: creating a shared reference to a mutable static
--> $DIR/reference-to-mut-static-unsafe-fn.rs:10:18
|
LL | let _y = &X;
| ^^ shared reference to mutable static
|
= note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
help: use `addr_of!` instead to create a raw pointer
|
LL | let _y = addr_of!(X);
| ~~~~~~~~~ +
```
