Look for `implied_bounds_in_impls` in more positions
With this, we lint `impl Trait` implied bounds in more positions:
- Type alias impl trait
- Associated type position impl trait
- Argument position impl trait
- these are not opaque types, but instead are desugared to `where` clauses, so we need extra logic for finding them (`check_generics`), however the rest of the logic is the same
Before this, we'd only lint RPIT `impl Trait`s.
"Hide whitespaces" and reviewing commits individually might make this easier
changelog: [`implied_bounds_in_impls`]: start linting implied bounds in APIT, ATPIT, TAIT
Merge `single_call_fn` post-crate visitor into lint pass
The `single_call_fn` lint worked by first collecting a list of function definitions in the lint pass, then populating the list of uses for each function in a second visitor after the crate is checked.
Doing another pass through the crate shouldn't be needed, and we should be able to do it in the same lint pass, by looking for path references to functions only and then processing them post-crate.
Other changes:
- `FxHashMap` -> `FxIndexMap` so that we emit warnings in a consistent order, as we see them (making the diff a bit confusing to look at, because warnings were moved around)
- no longer storing a `Vec<Span>` per function: an enum representing "seen once" or "seen more than once" should be enough (only the first element is used later)
- "used here" help is now a note
I also noticed that it lints on trait methods with a default implementation, but not on regular trait methods without a body (because that's what `check_fn` does). I'm not sure if that's useful though, maybe we shouldn't lint trait methods at all? It's not like you can avoid it sometimes (but then again it's a restriction lint). Either way, I left the behavior where it was before so that there are no functional changes made in this PR and it's purely a refactor. I can change it though
changelog: none
FIX(12243): redundant_guards
Fixed#12243
changelog: Fix[`redundant_guards`]
I have made a correction so that no warning does appear when y.is_empty() is used within a constant function as follows.
```rust
pub const fn const_fn(x: &str) {
match x {
// Shouldn't lint.
y if y.is_empty() => {},
_ => {},
}
}
```
Add new `unnecessary_get_then_check` lint
No issue linked to this as far as I can see. It's a lint I discovered that could be added when I worked on another lint.
r? `@llogiq`
changelog: Add new `unnecessary_get_then_check` lint
A warning is now suppressed when "<str_va> if <str_var>.is_empty" is used in a constant function.
FIX: instead of clippy_util::in_const
FIX: Merged `redundant_guards_const_fn.rs` into `redundant_guards.rs`.
Extend `unnecessary_to_owned` to handle `Borrow` trait in map types
Fixes https://github.com/rust-lang/rust-clippy/issues/8088.
Alternative to #12315.
r? `@y21`
changelog: Extend `unnecessary_to_owned` to handle `Borrow` trait in map types
----
UPDATE: add async block into test.
FIX: no_effect
Fixed asynchronous function parameter names with underscores so that warnings are not displayed when underscores are added to parameter names
ADD: test case
There are lots of functions that modify a diagnostic. This can be via a
`&mut Diagnostic` or a `&mut DiagnosticBuilder`, because the latter type
wraps the former and impls `DerefMut`.
This commit converts all the `&mut Diagnostic` occurrences to `&mut
DiagnosticBuilder`. This is a step towards greatly simplifying
`Diagnostic`. Some of the relevant function are made generic, because
they deal with both errors and warnings. No function bodies are changed,
because all the modifier methods are available on both `Diagnostic` and
`DiagnosticBuilder`.
This mostly works well, and eliminates a couple of delayed bugs.
One annoying thing is that we should really also add an
`ErrorGuaranteed` to `proc_macro::bridge::LitKind::Err`. But that's
difficult because `proc_macro` doesn't have access to `ErrorGuaranteed`,
so we have to fake it.
Ignore imported items in `min_ident_chars`
Suppress the `min_ident_chars` warning for items whose name we cannot control. Do not warn for `use a::b`, but warn for `use a::b as c`, since `c` is a local identifier.
Fixes#12232
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: [`min_ident_chars`]: Do not warn on non-local identifiers
[`incompatible_msrv`]: allow expressions that come from desugaring
Fixes#12273
changelog: [`incompatible_msrv`]: don't lint on the `IntoFuture::into_future` call desugared by `.await`
Suppress the `min_ident_chars` warning for items whose name we cannot
control. Do not warn for `use a::b`, but warn for `use a::b as c`, since
`c` is a local identifier.
Fixes#12232
[`implied_bounds_in_impls`]: avoid linting on overlapping associated tys
Fixes#11880
Before this change, we were simply ignoring associated types (except for suggestion purposes), because of an incorrect assumption (see the comment that I also removed).
For something like
```rs
trait X { type T; }
trait Y: X { type T; }
// Can't constrain `X::T` through `Y`
fn f() -> impl X<T = i32> + Y<T = u32> { ... }
```
We now avoid linting if the implied bound (`X<T = i32>`) "names" associated types that also exists in the implying trait (`trait Y`). Here that would be the case.
But if we only wrote `impl X + Y<T = u32>` then that's ok because `X::T` was never constrained in the first place.
I haven't really thought about how this interacts with GATs, but I think it's fine. Fine as in, it might create false negatives, but hopefully no false positives.
(The diff is slightly annoying because of formatting things. Really the only thing that changed in the if chain is extracting the `implied_by_def_id` which is needed for getting associated types from the trait, and of course actually checking for overlap)
cc `@Jarcho` ? idk if you want to review this or not. I assume you looked into this code a bit to find this bug.
changelog: [`implied_bounds_in_impls`]: avoid linting when associated type from supertrait can't be constrained through the implying trait bound
