Use ordinal number in argument error
Add an ordinal number to two argument errors ("unexpected" and "missing") for ease of understanding error.
```
error[E0061]: this function takes 3 arguments but 2 arguments were supplied
--> test.rs:11:5
|
11 | f(42, 'a');
| ^ --- 2nd argument of type `f32` is missing
|
(snip)
error[E0061]: this function takes 3 arguments but 4 arguments were supplied
--> test.rs:12:5
|
12 | f(42, 42, 1.0, 'a');
| ^ ----
| | |
| | unexpected 2nd argument of type `{integer}`
| help: remove the extra argument
```
To get an ordinal number, I copied `ordinalize` from other crate `rustc_resolve` because I think it is too much to link `rustc_resolve` for this small function. Please let me know if there is a better way.
Go over all structured parser suggestions and make them verbose style.
When suggesting to add or remove delimiters, turn them into multiple suggestion parts.
Use parenthetical notation for `Fn` traits
Always use the `Fn(T) -> R` format when printing closure traits instead of `Fn<(T,), Output = R>`.
Address #67100:
```
error[E0277]: expected a `Fn()` closure, found `F`
--> file.rs:6:13
|
6 | call_fn(f)
| ------- ^ expected an `Fn()` closure, found `F`
| |
| required by a bound introduced by this call
|
= note: wrap the `F` in a closure with no arguments: `|| { /* code */ }`
note: required by a bound in `call_fn`
--> file.rs:1:15
|
1 | fn call_fn<F: Fn() -> ()>(f: &F) {
| ^^^^^^^^^^ required by this bound in `call_fn`
help: consider further restricting this bound
|
5 | fn call_any<F: std::any::Any + Fn()>(f: &F) {
| ++++++
```
Always use the `Fn(T) -> R` format when printing closure traits instead of `Fn<(T,), Output = R>`.
Fix#67100:
```
error[E0277]: expected a `Fn()` closure, found `F`
--> file.rs:6:13
|
6 | call_fn(f)
| ------- ^ expected an `Fn()` closure, found `F`
| |
| required by a bound introduced by this call
|
= note: wrap the `F` in a closure with no arguments: `|| { /* code */ }`
note: required by a bound in `call_fn`
--> file.rs:1:15
|
1 | fn call_fn<F: Fn() -> ()>(f: &F) {
| ^^^^^^^^^^ required by this bound in `call_fn`
help: consider further restricting this bound
|
5 | fn call_any<F: std::any::Any + Fn()>(f: &F) {
| ++++++
```
Allow coercing functions whose signature differs in opaque types in their defining scope into a shared function pointer type
r? `@compiler-errors`
This accepts more code on stable. It is now possible to have match arms return a function item `foo` and a different function item `bar` in another, and that will constrain OpaqueTypeInDefiningScope to have the hidden type ConcreteType and make the type of the match arms a function pointer that matches the signature. So the following function will now compile, but on master it errors with a type mismatch on the second match arm
```rust
fn foo<T>(t: T) -> T {
t
}
fn bar<T>(t: T) -> T {
t
}
fn k() -> impl Sized {
fn bind<T, F: FnOnce(T) -> T>(_: T, f: F) -> F {
f
}
let x = match true {
true => {
let f = foo;
bind(k(), f)
}
false => bar::<()>,
};
todo!()
}
```
cc https://github.com/rust-lang/rust/issues/116652
This is very similar to https://github.com/rust-lang/rust/pull/123794, and with the same rationale:
> this is for consistency with `-Znext-solver`. the new solver does not have the concept of "non-defining use of opaque" right now and we would like to ideally keep it that way. Moving to `DefineOpaqueTypes::Yes` in more cases removes subtlety from the type system. Right now we have to be careful when relating `Opaque` with another type as the behavior changes depending on whether we later use the `Opaque` or its hidden type directly (even though they are equal), if that later use is with `DefineOpaqueTypes::No`*
Start pointing to where bindings were declared when they are captured in closures:
```
error[E0597]: `x` does not live long enough
--> $DIR/suggest-return-closure.rs:23:9
|
LL | let x = String::new();
| - binding `x` declared here
...
LL | |c| {
| --- value captured here
LL | x.push(c);
| ^ borrowed value does not live long enough
...
LL | }
| -- borrow later used here
| |
| `x` dropped here while still borrowed
```
Suggest cloning in more cases involving closures:
```
error[E0507]: cannot move out of `foo` in pattern guard
--> $DIR/issue-27282-move-ref-mut-into-guard.rs:11:19
|
LL | if { (|| { let mut bar = foo; bar.take() })(); false } => {},
| ^^ --- move occurs because `foo` has type `&mut Option<&i32>`, which does not implement the `Copy` trait
| |
| `foo` is moved here
|
= note: variables bound in patterns cannot be moved from until after the end of the pattern guard
help: consider cloning the value if the performance cost is acceptable
|
LL | if { (|| { let mut bar = foo.clone(); bar.take() })(); false } => {},
| ++++++++
```
- Firstly get all the information about generics matching out of the HIR
- Secondly the labelling for the function is more coherent now
- Lastly a few error message improvements
This function is now used to check `#[panic_handler]`, `start` lang item, `main`, `#[start]` and intrinsic functions.
The diagnosis produced are now closer to the ones produced by trait/impl method signature mismatch.
This solves a regression where `0.0.cmp()` was ambiguous when a custom
trait with a `cmp` method was in scope.
FOr integers it shouldn't be a problem in practice so I wasn't able to
add a test.
- On compiler-error's suggestion of moving this lower down the stack,
along the path of `report_mismatched_types()`, which is used
by `rustc_hir_analysis` and `rustc_hir_typeck`.
- update ui tests, add test
- add suggestions for references to fn pointers
- modify `TypeErrCtxt::same_type_modulo_infer` to take `T: relate::Relate` instead of `Ty`