Commit Graph

67 Commits

Author SHA1 Message Date
Esteban Küber
028a920c53 Tweak fn pointer suggestion span
Use a more targeted span when suggesting casting an `fn` item to an `fn` pointer.

```
error[E0308]: cannot coerce functions which must be inlined to function pointers
  --> $DIR/cast.rs:10:33
   |
LL |     let _: fn(isize) -> usize = callee;
   |            ------------------   ^^^^^^ cannot coerce functions which must be inlined to function pointers
   |            |
   |            expected due to this
   |
   = note: expected fn pointer `fn(_) -> _`
                 found fn item `fn(_) -> _ {callee}`
   = note: fn items are distinct from fn pointers
help: consider casting to a fn pointer
   |
LL |     let _: fn(isize) -> usize = callee as fn(isize) -> usize;
   |                                        +++++++++++++++++++++
```
```
error[E0308]: mismatched types
  --> $DIR/fn-pointer-mismatch.rs:42:30
   |
LL |     let d: &fn(u32) -> u32 = foo;
   |            ---------------   ^^^ expected `&fn(u32) -> u32`, found fn item
   |            |
   |            expected due to this
   |
   = note: expected reference `&fn(_) -> _`
                found fn item `fn(_) -> _ {foo}`
help: consider using a reference
   |
LL |     let d: &fn(u32) -> u32 = &foo;
   |                              +
```
Previously we'd point at the whole expression for replacement, instead of marking what was being added.

We could also modify the suggestions for `&(name as fn())`, but for that we require storing more accurate spans than we have now.
2025-02-02 00:46:02 +00:00
Jacob Pratt
64550d1ed8
Rollup merge of #136032 - estebank:issue-136028, r=SparrowLii
Account for mutable borrow in argument suggestion

```
error: value assigned to `object` is never read
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:21:5
   |
LL |     object = &mut object2;
   |     ^^^^^^
   |
help: you might have meant to mutate the pointed at value being passed in, instead of changing the reference in the local binding
   |
LL ~ fn change_object3(object: &mut Object) {
LL |
LL |     let object2 = Object;
LL ~     *object = object2;
   |
```
instead of
```
error: value assigned to `object` is never read
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:21:5
   |
LL |     object = &mut object2;
   |     ^^^^^^
   |
help: you might have meant to mutate the pointed at value being passed in, instead of changing the reference in the local binding
   |
LL ~ fn change_object3(object: &mut mut Object) {
LL |
LL |     let object2 = Object;
LL ~     *object = object2;
   |
```

Fix #136028.
2025-01-25 23:27:01 -05:00
Esteban Küber
1dfc437aaf Account for mutable borrow in argument suggestion
```
error: value assigned to `object` is never read
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:21:5
   |
LL |     object = &mut object2;
   |     ^^^^^^
   |
help: you might have meant to mutate the pointed at value being passed in, instead of changing the reference in the local binding
   |
LL ~ fn change_object3(object: &mut Object) {
LL |
LL |     let object2 = Object;
LL ~     *object = object2;
   |
```
instead of
```
error: value assigned to `object` is never read
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:21:5
   |
LL |     object = &mut object2;
   |     ^^^^^^
   |
help: you might have meant to mutate the pointed at value being passed in, instead of changing the reference in the local binding
   |
LL ~ fn change_object3(object: &mut mut Object) {
LL |
LL |     let object2 = Object;
LL ~     *object = object2;
   |
```

Fix #136028.
2025-01-24 23:34:34 +00:00
许杰友 Jieyou Xu (Joe)
8a0310a0b1 tests: use needs-subprocess instead of ignore-{wasm32,emscripten,sgx} 2025-01-23 20:51:29 +08:00
Esteban Küber
4438b3211f review comments and make test run-rustfix 2025-01-11 01:58:32 +00:00
Esteban Küber
ec98df4bb6 On unused assign lint, detect mut arg: &Ty meant to be arg: &mut Ty
```
error: value assigned to `object` is never read
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:11:5
   |
LL |     object = &object2;
   |     ^^^^^^
   |
note: the lint level is defined here
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:1:9
   |
LL | #![deny(unused_assignments, unused_variables)]
   |         ^^^^^^^^^^^^^^^^^^
help: you might have meant to mutate the pointed at value being passed in, instead of changing the reference in the local binding
   |
LL ~ fn change_object2(object: &mut Object) {
LL |     let object2 = Object;
LL ~     *object = object2;
   |
```

This might be the first thing someone tries to write to mutate the value *behind* an argument, trying to avoid an E0308.
2025-01-11 01:34:23 +00:00
Esteban Küber
c2ae386c85 On E0308, detect mut arg: &Ty meant to be arg: &mut Ty
```
error[E0308]: mismatched types
  --> $DIR/mut-arg-of-borrowed-type-meant-to-be-arg-of-mut-borrow.rs:6:14
   |
LL | fn change_object(mut object: &Object) {
   |                              ------- expected due to this parameter type
LL |     let object2 = Object;
LL |     object = object2;
   |              ^^^^^^^ expected `&Object`, found `Object`
   |
help: you might have meant to mutate the pointed at value being passed in, instead of changing the reference in the local binding
   |
LL ~ fn change_object(object: &mut Object) {
LL |     let object2 = Object;
LL ~     *object = object2;
   |
```

This might be the first thing someone tries to write to mutate the value *behind* an argument. We avoid suggesting `object = &object2;`, as that is less likely to be what was intended.
2025-01-11 01:34:23 +00:00
Esteban Küber
57f9f8f883 Add test for mut arg: &Ty meant to be arg: &mut Ty
This is a mistake I've seen newcomers make where they want to express an "out" argument.
2025-01-11 01:34:23 +00:00
dianne
fe8b12f8cf only avoid blaming assignments from argument patterns 2025-01-06 16:12:11 -08:00
dianne
10061b3a4f make outlives constraints from generic arguments less boring 2025-01-06 16:12:11 -08:00
dianne
6421d4cf80 best_blame_constraint: prioritize blaming interesting-seeming constraints 2025-01-06 16:12:11 -08:00
dianne
50222dba2e best_blame_constraint: avoid blaming assignments without user-provided types 2025-01-06 16:12:11 -08:00
dianne
ac922245f0 best_blame_constraint: don't filter constraints by sup SCC
The SCCs of the region graph are not a reliable heuristic to use for blaming an interesting
constraint for diagnostics. For region errors, if the outlived region is `'static`, or the involved
types are invariant in their lifetiems, there will be cycles in the constraint graph containing both
the target region and the most interesting constraints to blame. To get better diagnostics in these
cases, this commit removes that heuristic.
2025-01-06 16:08:29 -08:00
Guillaume Gomez
0d9a57d979
Rollup merge of #133470 - jieyouxu:ugly, r=compiler-errors
Cleanup: delete `//@ pretty-expanded` directive

This PR removes the `//@ pretty-expanded` directive support in compiletest and removes its usage inside ui tests because it does not actually do anything, and its existence is itself misleading. This PR is split into two commits:

1. The first commit just drops `pretty-expanded` directive support in compiletest.
2. The second commit is created by `sd '//@ pretty-expanded.*\n' '' tests/ui/**/*.rs`[^1], reblessing, and slightly adjusting some leading whitespace in a few tests.

We can tell this is fully removed because compiletest doesn't complain about unknown directive when running the `ui` test suite.

cc #23616

### History

Originally, there was some effort to introduce more test coverage for `-Z unpretty=expanded` (in 2015 this was called `--pretty=expanded`). In [Make it an error to not declare used features #23598][pr-23598], there was a flip from `//@ no-pretty-expanded` (opt-out of `-Z
unpretty=expanded` test) to `//@ pretty-expanded` (opt-in to `-Z unpretty=expanded` test). This was needed because back then the dedicated `tests/pretty` ("pretty") test suite did not existed, and the pretty tests were grouped together under `run-pass` tests (I believe the `ui` test suite didn't exist back then either). Unfortunately, in this process the replacement `//@ pretty-expanded` directives contained a `FIXME #23616` linking to [There are very few tests for `-Z unpretty` expansion #23616][issue-23616]. But this was arguably backwards and somewhat misleading, as noted in [#23616](https://github.com/rust-lang/rust/issues/23616#issuecomment-484999901):

    The attribute is off by default and things just work if you don't
    test it, people have not been adding the `pretty-expanded`
    annotation to new tests even if it would work.

Which basically renders this useless.

### Current status

As of Nov 2024, we have a dedicated `pretty` test suite, and some time over the years the split between `run-pass` into `ui` and `pretty` test suites caused all the `//@ pretty-expanded` in `ui` tests to do absolutely nothing: the compiletest logic for `pretty-expanded` only triggers in the *pretty* test suite, but none of the pretty tests use it. Oops.

Nobody remembers this, nobody uses this, it's misleading in ui tests. Let's get rid of this directive altogether.

[pr-23598]: https://github.com/rust-lang/rust/pull/23598
[issue-23616]: https://github.com/rust-lang/rust/issues/23616

### Follow-ups

- [x] Yeet this directive from rustc-dev-guide docs. https://github.com/rust-lang/rustc-dev-guide/pull/2147

[^1]: https://github.com/chmln/sd

r? compiler
2024-11-26 15:32:18 +01:00
许杰友 Jieyou Xu (Joe)
95ff642797 tests: remove //@ pretty-expanded usages
Done with

```bash
sd '//@ pretty-expanded.*\n' '' tests/ui/**/*.rs
```

and

```
sd '//@pretty-expanded.*\n' '' tests/ui/**/*.rs
```
2024-11-26 02:50:48 +08:00
Michael Goulet
d26e29ff3a Tweak parameter mismatch explanation to not say unknown 2024-11-25 03:04:07 +00:00
Michael Goulet
6a891ec4fe Enforce supertrait outlives obligations hold when confirming impl 2024-08-05 09:55:14 -04:00
Michael Goulet
91acacf85b Peel off explicit (or implicit) deref before suggesting clone on move error in borrowck 2024-07-26 14:41:56 -04:00
Matthias Krüger
2b34490da6
Rollup merge of #125042 - long-long-float:suggest-move-arg-outside, r=fmease
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.
2024-07-17 16:22:26 +02:00
long-long-float
332b41dbce Use ordinal number in argument error
Fix error message

Fix tests

Format
2024-07-14 13:50:09 +09:00
Esteban Küber
692bc344d5 Make parse error suggestions verbose and fix spans
Go over all structured parser suggestions and make them verbose style.

When suggesting to add or remove delimiters, turn them into multiple suggestion parts.
2024-07-12 03:02:57 +00:00
yukang
81c86ddf8e show fnsig's output when there is difference 2024-07-06 23:29:58 +08:00
Esteban Küber
ff92ab0903 More accurate mutability suggestion 2024-07-04 05:36:34 +00:00
bors
1d52972dd8 Auto merge of #125778 - estebank:issue-67100, r=compiler-errors
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) {
  |                              ++++++
```
2024-06-03 08:14:03 +00:00
León Orell Valerian Liehr
34c56c45cf
Rename HIR TypeBinding to AssocItemConstraint and related cleanup 2024-05-30 22:52:33 +02:00
Esteban Küber
e6bd6c2044 Use parenthetical notation for Fn traits
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) {
  |                              ++++++
```
2024-05-29 22:26:54 +00:00
Matthias Krüger
abcf400a28
Rollup merge of #124297 - oli-obk:define_opaque_types13, r=jackh726
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`*
2024-05-23 14:09:22 +02:00
Esteban Küber
4aba2c55e6 Modify find_expr from Span to better account for closures
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 } => {},
   |                                         ++++++++
```
2024-04-24 22:21:13 +00:00
Oli Scherer
5c55d6a128 Register hidden types when equating function definitions in coercion 2024-04-24 10:05:33 +00:00
Oli Scherer
ca4a18fafc Add some FnDef LUB coercion tests 2024-04-24 10:05:32 +00:00
Oli Scherer
c24148ef7b Allow coercing functions whose signature differs in opaque types in their defining scope into a shared function pointer type 2024-04-23 14:38:17 +00:00
Oli Scherer
a18f043033 Add regression test 2024-04-23 14:30:46 +00:00
Esteban Küber
bce78102c3 Account for unops when suggesting cloning 2024-04-11 16:41:41 +00:00
Esteban Küber
fa2fc3ab96 Suggest .clone() when moved while borrowed 2024-04-11 16:41:41 +00:00
lcnr
2b67f0104a check FnDef return type for WF 2024-04-04 01:55:29 +01:00
Matthias Krüger
0c8c18fcc6
Rollup merge of #123291 - c410-f3r:testsssssss, r=petrochenkov
Move some tests

r? `@petrochenkov`
2024-04-03 22:11:01 +02:00
Caio
4c0aea0d47 Move some tests 2024-03-31 14:58:17 -03:00
Steven Trotter
8a5245e7dd Refactored a few bits:
- 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
2024-03-15 13:37:41 +00:00
Steven Trotter
df93364057 Added ability to report on generic argument mismatch better
Needs some checking over and some tests have altered that need sanity checking, but overall this is starting to get somewhere now.
2024-03-15 08:37:32 +00:00
许杰友 Jieyou Xu (Joe)
ec2cc761bc
[AUTO-GENERATED] Migrate ui tests from // to //@ directives 2024-02-16 20:02:50 +00:00
Oli Scherer
5f6390f947 Continue compilation after check_mod_type_wf errors 2024-02-14 11:00:30 +00:00
Oli Scherer
eab2adb660 Continue to borrowck even if there were previous errors 2024-02-08 08:10:43 +00:00
Oli Scherer
0978f6e010 Avoid silencing relevant follow-up errors 2024-01-09 21:08:16 +00:00
jyn
b5d8361909 rename to verbose-internals 2023-12-19 13:35:37 -05:00
jyn
eb53721a34 recurse into refs when comparing tys for diagnostics 2023-12-07 23:00:46 -05:00
Nilstrieb
41e8d152dc Show number in error message even for one error
Co-authored-by: Adrian <adrian.iosdev@gmail.com>
2023-11-24 19:15:52 +01:00
Michael Goulet
c83f642f12 Pretty print Fn traits in rustc_on_unimplemented 2023-11-02 20:57:05 +00:00
Ali MJ Al-Nasrawy
a8830631b9 remove trailing dots 2023-10-08 10:06:17 +00:00
Ali MJ Al-Nasrawy
996ffcb718 always show and explain sub region 2023-10-08 09:59:51 +00:00
Eduardo Sánchez Muñoz
c599761140 rustc_hir_analysis: add a helper to check function the signature mismatches
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.
2023-09-19 18:15:23 +02:00