Fix LitKind's byte buffer to use refcounted slice
While working on adding a new lint for clippy (see https://github.com/rust-lang/rust-clippy/pull/6044) for avoiding shared ownership of "mutable buffer" types (such as using `Rc<Vec<T>>` instead of `Rc<[T]>`), I noticed a type exported from rustc_ast and used by clippy gets caught by the lint. This PR fixes the exported type.
This PR includes the actual change to clippy too, but I will open a PR directly against clippy for that part (although it will currently fail to build there).
unnecessary sort by: avoid dereferencing the suggested closure parameter
This change tries to simplify the solution for problematic cases but is less restrictive than #6006.
* We can't dereference shared references to non-Copy types, so the new suggestion does not do that. Note that this implies that the suggested closure parameter will be a reference.
* We can't take a reference to the closure parameter in the returned key, so we don't lint in those cases. This can happen either because the key borrows from the parameter (e.g. `|a| a.borrows()`), or because we suggest `|a| Reverse(a)`. If we did we would hit this error:
```
error: lifetime may not live long enough
--> /home/ebroto/src/ebroto-clippy/tests/ui/unnecessary_sort_by.fixed:19:25
|
19 | vec.sort_by_key(|b| Reverse(b));
| -- ^^^^^^^^^^ returning this value requires that `'1` must outlive `'2`
| ||
| |return type of closure is Reverse<&'2 isize>
| has type `&'1 isize`
error: aborting due to previous error
```
Note that Clippy does not currently have the (MIR-based) machinery necessary to check that what is borrowed is actually the closure parameter.
changelog: [`unnecessary_sort_by`]: avoid dereferencing the suggested closure parameter
Fixes#6001
Do not lint float fractions in `mistyped_literal_suffixes`
As suggested in https://github.com/rust-lang/rust-clippy/issues/4706#issuecomment-544797928, the fractional part is now ignored (the integer part is checked instead).
Fixes: #4706
changelog: `mistyped_literal_suffixes` no longer warns on the fractional part of a float (e.g. 713.23_64)
Lint for invisible Unicode characters other than ZWSP
This PR extends the existing `zero_width_space` lint to look for other invisible characters as well (in this case, `\\u{ad}` soft hyphen.
I feel like this lint is the logical place to add the check, but I also realize the lint name is not particularly flexible, but I also understand that it shouldn't be renamed for compatibility reasons.
Open questions:
- What other characters should trigger the lint?
- What should be done with the lint name?
- How to indicate the change in functionality?
Motivation behind this PR: https://github.com/rust-lang/rust/issues/77417 - I managed to shoot myself in the foot by an invisible character pasted into my test case.
changelog: rename [`zero_width_space`] to [`invisible_characters`] and add SHY and WJ to the list.
Downgrade interior_mutable_const lints to warn by default
This change updates the two lints in the file non_copy_const.rs to be warn by default rather than deny by default. It also updates the known problems for declare_interior_mutable_const to mention some issues that are affected by the lints.
This is a repeat pull request since I botched the first one (#6012). Apart from my messing up the commits of that one, I also had a problem where the stderr of the tests didn't change despite me changing both lints to warn by default. Is this normal behaviour for some lints or do I need to adjust the tests to accommodate the change?
fixes#5863
changelog: none
Don't emit a lint for the suggestion leading to errors in `needless_range_loop`
Fix#5945
changelog: Don't emit a lint for the suggestion leading to errors in `needless_range_loop`
needless arbitrary self: handle macros
This fixes two cases related to macros:
* If the parameter comes from expansion, do not lint as the user has no possibility of changing it. This is not directly related to the fixed issue, but we should probably do that.
* If *only* the lifetime name comes from expansion, lint, but allow the user decide the name of the lifetime. In the related issue, the lifetime was unnamed and then renamed by `async_trait`, so just removing the name in the suggestion would work, but in the general case a macro can rename a lifetime that was named differently, and we can't reliably know that name anymore.
As a hint for the reviewer, the expanded code for the test can be checked with this command (from the root dir of the repo):
```sh
rustc -L target/debug/test_build_base/needless_arbitrary_self_type_unfixable.stage-id.aux -Zunpretty=expanded tests/ui/needless_arbitrary_self_type_unfixable.rs
```
changelog: [`needless_arbitrary_self_type`]: handle macros
Fixes#6089
