new lint: `unnecessary_fallible_conversions`
Closes#11577
A new lint that looks for calls such as `i64::try_from(1i32)` and suggests `i64::from(1i32)`. See lint description (and linked issue) for more details for why.
There's a tiny bit of overlap with the `useless_conversion` lint, in that the other one warns `T::try_from(T)` (i.e., fallibly converting to the same type), so this lint ignores cases like `i32::try_from(1i32)` to avoid emitting two warnings for the same expression.
Also, funnily enough, with this one exception, this lint would warn on exactly every case in the `useless_conversion_try` ui test that `useless_conversion` didn't cover (but never two warnings at the same time), which is neat. I did add an `#![allow]` though since we don't want interleaved warnings from multiple lints in the same uitest.
changelog: new lint: `unnecessary_fallible_conversions`
fix enum_variant_names depending lint depending on order
changelog: [`enum_variant_names`]: fix single word variants preventing lint of later variant pre/postfixed with the enum name
fixes#11494
Single word variants prevented checking the `check_enum_start` and `check_enum_end` for being run on later variants
Use multiple pushes in `vec_init_then_push` example
Makes the perf argument clearer, since a single push doesn't have unnecessary allocations compared to `vec![x]`
changelog: none
Remove internal feature from clippy_utils
It's only used to gate a few `const`s, removing the feature gate means it doesn't have to be recompiled when moving between a normal and `-F internal` build/test/etc
changelog: none
ignore lower-camel-case words in `doc_markdown`
This fixes#11568 by ignoring camelCase words starting with a lower case letter.
r? `@blyxyas`
---
changelog: none
move `read_zero_byte_vec` to nursery
I think the concerns in #9274 are valid, and we should move this to nursery while we're reworking this.
changelog: [`read_zero_byte_vec`] moved to nursery
Expand docs on clippy::todo
https://doc.rust-lang.org/nightly/core/macro.todo.html describes that `todo!()` is intended for explicitly unfinished code. Explain this, and mention `unimplemented!()` as an alternative.
Whilst we're here, improve the punctuation on the other lints.
changelog: [`todo`]: expand docs
Fix missing parenthesis in suboptimal floating point help
This fixes#11559 by adding a branch in the `Neg` implementation for `Sugg` that adds parentheses to keep precedence in order, then using that in the suggestion. I also removed some needless `.to_string()`s while I was at it.
---
changelog: none
[`iter_without_into_iter`]: fix papercuts in suggestion and restrict linting to exported types
See #11692 for more context.
tldr: the lint `iter_without_into_iter` has suggestions that don't compile, which imo isn't that problematic because it does have the appropriate `Applicability` that tells external tools that it shouldn't be auto-applied.
However there were some obvious "errors" in the suggestion that really should've been included in my initial PR adding the lint, which is fixed by this PR:
- `IntoIterator::into_iter` needs a `self` argument.
- `IntoIterator::Iter` associated type doesn't exist. This should've just been `Item`.
This still doesn't make it machine applicable, and the remaining things are imho quite non-trivial to implement, as I've explained in https://github.com/rust-lang/rust-clippy/issues/11692#issuecomment-1773886111.
I personally think it's fine to leave it there and let the user change the remaining errors when copy-pasting the suggestion (e.g. errors caused by lifetimes that were permitted in fn return-position but are not in associated types).
This is how many of our other lint suggestions already work.
Also, we now restrict linting to only exported types. This required moving basically all of the tests around since they were previously in the `main` function. Same for `into_iter_without_iter`. The git diff is a bit useless here...
changelog: [`iter_without_into_iter`]: fix papercuts in suggestion and restrict linting to exported types
(cc `@lopopolo,` figured I should mention you since you created the issue)
https://doc.rust-lang.org/nightly/core/macro.todo.html
describes that `todo!()` is intended for explicitly unfinished
code. Explain this, and mention `unimplemented!()` as an alternative.
Whilst we're here, improve the punctuation on the other lints.
Add `waker_clone_and_wake` lint to check needless `Waker` clones
Check for patterns of `waker.clone().wake()` and replace them with `waker.wake_by_ref()`.
An alternative name could be `waker_clone_then_wake`
changelog: [ `waker_clone_wake`]: new lint
Remove the `internal_warn` lint category
`LINT_AUTHOR` and `DUMP_HIR` can be removed since their corresponding lint passes are only used for side effects
The metadata collector lint can be made an `internal` lint since `clippy::internal` is set to deny when running the collector
Also renames some internal lints/passes
changelog: none
Create `clippy_config` crate, hide internal representation from docs
r? `@flip1995`
The first commit moves a decent chunk of code out of `clippy_lints`/`clippy_utils` into a new crate `clippy_config`
The second commit changes how `--explain`, the book and the site render configuration values. The internal type is now hidden and the displayed defaults are now valid TOML values instead of `Debug` output
changelog: none
Set doc-tests to `no_run`
This excludes `should_panic` tests, those are still run to ensure they panic. Most of our other doc snippets don't gain much from being run though so this frees up a nice bit of CI time
It also fixes the occasional issue such as `foo.txt`s being created f942470ca7/clippy_lints/src/permissions_set_readonly_false.rs (L19)
changelog: none
suggest passing function instead of calling it in closure for [`option_if_let_else`]
fixes: #11429
changelog: suggest passing function instead of calling it in closure for [`option_if_let_else`]
Skip if_not_else lint for '!= 0'-style checks
Currently, clippy makes unhelpful suggestions such as this:
```
warning: unnecessary `!=` operation
--> src/vm.rs:598:36
|
598 | *destination = if source & 0x8000 != 0 { 0xFFFF } else { 0 };
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: change to `==` and swap the blocks of the `if`/`else`
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#if_not_else
= note: `-W clippy::if-not-else` implied by `-W clippy::pedantic`
```
Bit tests often take on the form `if foo & 0x1234 != 0 { … } else { … }`, and the `!= 0` part reads as "has any bits set". Therefore, this code already has the "correct" order, and shouldn't be changed.
This PR disables the lint for these cases, and in fact all cases where the condition is "foo is non-zero".
I did my homework:
- \[X] Followed [lint naming conventions][lint_naming] → Not applicable, this PR fixes an existing lint
- \[X] Added passing UI tests (including committed `.stderr` file) → Yes, `tests/ui/if_not_else_bittest.rs`
- \[X] `cargo test` passes locally
- \[X] Executed `cargo dev update_lints`
- \[X] Added lint documentation → Not applicable, this PR fixes an existing lint
- \[X] Run `cargo dev fmt`
changelog: Fix [`if_not_else`] false positive when something like `bitflags != 0` is used
[`map_identity`]: recognize tuple identity function
Fixes#7189
This lint now recognizes `.map(|(a, b)| (a, b))` as a useless `map` call.
changelog: [`map_identity`]: recognize tuple identity function
Now `declare_interior_mutable_const` and `borrow_interior_mutable_const` respect the `ignore-interior-mutability` configuration entry
Fix#10537
changelog: Now `declare_interior_mutable_const` and `borrow_interior_mutable_const` respect the `ignore-interior-mutability` configuration entry
[`map_identity`]: allow closure with type annotations
Fixes#9122
`.map(|a: u32| a)` can help type inference, so we should probably allow this and not warn about "unnecessary map of the identity function"
changelog: [`map_identity`]: allow closure with type annotations
Implement rustc part of RFC 3127 trim-paths
This PR implements (or at least tries to) [RFC 3127 trim-paths](https://github.com/rust-lang/rust/issues/111540), the rustc part. That is `-Zremap-path-scope` with all of it's components/scopes.
`@rustbot` label: +F-trim-paths
