rust/tests/ui/higher-ranked
Matthias Krüger af99946700
Rollup merge of #120507 - estebank:issue-108428, r=davidtwco
Account for non-overlapping unmet trait bounds in suggestion

When a method not found on a type parameter could have been provided by any
of multiple traits, suggest each trait individually, instead of a single
suggestion to restrict the type parameter with *all* of them.

Before:

```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
  --> $DIR/method-on-unbounded-type-param.rs:5:10
   |
LL |     (&a).cmp(&b)
   |          ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
   |
   = note: the following trait bounds were not satisfied:
           `T: Ord`
           which is required by `&T: Ord`
           `&T: Iterator`
           which is required by `&mut &T: Iterator`
           `T: Iterator`
           which is required by `&mut T: Iterator`
help: consider restricting the type parameters to satisfy the trait bounds
   |
LL | fn g<T>(a: T, b: T) -> std::cmp::Ordering where T: Iterator, T: Ord {
   |                                           +++++++++++++++++++++++++
```

After:

```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
  --> $DIR/method-on-unbounded-type-param.rs:5:10
   |
LL |     (&a).cmp(&b)
   |          ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
   |
   = note: the following trait bounds were not satisfied:
           `T: Ord`
           which is required by `&T: Ord`
           `&T: Iterator`
           which is required by `&mut &T: Iterator`
           `T: Iterator`
           which is required by `&mut T: Iterator`
   = help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
   |
LL | fn g<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
   |       +++++
LL | fn g<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
   |       ++++++++++
```

Fix #108428.

Follow up to #120396, only last commit is relevant.
2024-02-06 22:45:42 +01:00
..
subtype recurse into refs when comparing tys for diagnostics 2023-12-07 23:00:46 -05:00
trait-bounds Rollup merge of #120507 - estebank:issue-108428, r=davidtwco 2024-02-06 22:45:42 +01:00
higher-lifetime-bounds.rs Simple modification of diagnostic information 2023-12-21 10:17:11 +08:00
higher-lifetime-bounds.stderr Simple modification of diagnostic information 2023-12-21 10:17:11 +08:00
higher-ranked-lifetime-error.rs Try to use approximate placeholder regions when outputting an AscribeUserType error in borrowck 2023-09-24 02:10:30 -04:00
higher-ranked-lifetime-error.stderr use Vec for region constraints 2023-12-17 07:31:07 +00:00
leak-check-in-selection.rs update use of feature flags 2023-12-14 15:22:37 +01:00