This lint checks if Option::take() is used on a temporary value (a value
that is not of type &mut Option and that is not a Place expression) to
suggest omitting take()
Check for loops/closures in `local_used_after_expr`
Follow up to #8646, catches when a local is used multiple times because it's in a loop or a closure
changelog: none
fix unnecessary_to_owned about msrv
This PR fixes ``[`unnecessary_owned`]``.
## What
```rust
# sample code
fn _msrv_1_35() {
#![clippy::msrv = "1.35"]
let _ = &["x"][..].to_vec().into_iter();
}
fn _msrv_1_36() {
#![clippy::msrv = "1.36"]
let _ = &["x"][..].to_vec().into_iter();
}
```
If we will check this code using clippy, ``[`unnecessary_owned`]`` will modify the code as follows.
```rust
error: unnecessary use of `to_vec`
--> $DIR/unnecessary_to_owned.rs:219:14
|
LL | let _ = &["x"][..].to_vec().into_iter();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use: `["x"][..].iter().copied()`
error: unnecessary use of `to_vec`
--> $DIR/unnecessary_to_owned.rs:224:14
|
LL | let _ = &["x"][..].to_vec().into_iter();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use: `["x"][..].iter().copied()`
```
This is incorrect. Because `Iterator::copied` was estabilished in 1.36.
## Why
This bug was caused by not separating "copied" and "clone" by reference to msrv.
89ee6aa6e3/clippy_lints/src/methods/unnecessary_to_owned.rs (L195)
So, I added a conditional branch and described the corresponding test.
Thank you in advance.
changelog: fix wrong suggestions about msrv in [`unnecessary_to_owned`]
r! `@giraffate`
Don't lint `manual_non_exhaustive` when the enum variant is used
fixes#5714
changelog: Don't lint `manual_non_exhaustive` when the enum variant is used
Do not trigger ``[`rest_pat_in_fully_bound_structs`]`` on `#[non_exhaustive]` structs
fixes#8029
Just adds an additional check to ensure that the`ty::VariantDef` is not marked as `#[non_exhaustive]`.
changelog: Do not apply ``[`rest_pat_in_fully_bound_structs`]`` on structs marked as non exhaustive.
New lint `is_digit_ascii_radix`
Closes#6399
changelog: Added [`is_digit_ascii_radix`]: recommend `is_ascii_digit()` or `is_ascii_hexdigit()` in place of `is_digit(10)` and `is_digit(16)`
Fix subtraction overflow in `cast_possible_truncation`
changelog: Fix false negative due to subtraction overflow in `cast_possible_truncation`
I *think* a false negative is the worst that can happen from this
Don't lint various match lints when expanded by a proc-macro
fixes#4952
As always for proc-macro output this is a hack-job of a fix. It would be really nice if more proc-macro authors would set spans correctly.
changelog: Don't lint various lints on proc-macro output.
Fix `same_functions_in_if_condition` FP
fixes#8139
changelog: Don't consider `Foo<{ SomeConstant }>` and `Foo<{ SomeOtherConstant }>` to be the same, even if the constants have the same value.
Remove overlap between `manual_split_once` and `needless_splitn`
changelog: Remove overlap between [`manual_split_once`] and [`needless_splitn`]. Fixes some incorrect `rsplitn` suggestions for [`manual_split_once`]
Things that can trigger `needless_splitn` no longer trigger `manual_split_once`, e.g.
```rust
s.[r]splitn(2, '=').next();
s.[r]splitn(2, '=').nth(0);
s.[r]splitn(3, '=').next_tuple();
```
Fixes some suggestions:
```rust
let s = "should not match";
s.rsplitn(2, '.').nth(1);
// old -> Some("should not match")
Some(s.rsplit_once('.').map_or(s, |x| x.0));
// new -> None
s.rsplit_once('.').map(|x| x.0);
s.rsplitn(2, '.').nth(1)?;
// old -> "should not match"
s.rsplit_once('.').map_or(s, |x| x.0);
// new -> early returns
s.rsplit_once('.')?.0;
```
- Create hir_crate_items query which traverses tcx.hir_crate(()).owners to return a hir::ModuleItems
- use tcx.hir_crate_items in tcx.hir().items() to return an iterator of hir::ItemId
- add par_items(impl Fn(hir::ItemId)) to traverse all items in parallel
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
ignore `&x | &y` in unnested_or_patterns
replacing it with `&(x | y)` is actually more characters
Fixes#6973
changelog: [`unnested_or_patterns`] ignore `&x | &y`, nesting would result in more characters
Add a lint to detect cast to unsigned for abs() and suggest unsigned_…
…abs()
changelog: Add a [`cast_abs_to_unsigned`] that checks for uses of `abs()` that are cast to the corresponding unsigned integer type and suggest to replace them with `unsigned_abs()`.
Fix `as_deref_mut` false positives in `needless_option_as_deref`
Also moves it into `methods/`
Fixes#7846Fixes#8047
changelog: [`needless_option_as_deref`]: No longer lints for `as_deref_mut` on Options that cannot be moved
supersedes #8064
fix FP in lint `[needless_match]`
fixes: #8542fixes: #8551fixes: #8595fixes: #8599
---
changelog: check for more complex custom type, and ignore type coercion in [`needless_match`]
Suggest from_utf8_unchecked in const contexts
Unfortunately I couldn't figure out how to check whether a given expression is in an `unsafe` context or not, so I just unconditionally emit the wrapping `unsafe {}` block in the suggestion. If there is an easy way to get it to work better then I would love to hear it.
changelog: Suggest `from_utf8_unchecked` instead of `from_utf8` in const contexts for ``[`transmute_bytes_to_str`]``
refs: #8379
Fix unnecessary_cast suggestion for type aliasses
Fix#6923. The [`unnecessary_cast`] lint now will skip casting to non-primitive type.
changelog: fix lint [`unnecessary_cast `]
`indexing_slicing` should not fire if a valid array index comes from a constant function that is evaluated at compile-time
fix#8348
changelog: [`indexing_slicing`] fewer false positives in `const` contexts and with `const` indices
Rework `undocumented_unsafe_blocks`
fixes: #8264fixes: #8449
One thing came up while working on this. Currently comments on the same line are supported like so:
```rust
/* SAFETY: reason */ unsafe {}
```
Is this worth supporting at all? Anything other than a couple of words doesn't really fit well.
edit: [zulip topic](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/.60undocumented_unsafe_blocks.60.20same.20line.20comment)
changelog: Don't lint `undocumented_unsafe_blocks` when the unsafe block comes from a proc-macro.
changelog: Don't lint `undocumented_unsafe_blocks` when the preceding line has a safety comment and the unsafe block is a sub-expression.
add `empty_structs_with_brackets`
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Closes#8591
I'm already sorry for the massive diff 😅
changelog: New lint [`empty_structs_with_brackets`]
single_element_loop: handle arrays for Edition2021
changelog: [`single_element_loop`] handle arrays in Edition 2021, handle `.iter_mut()` and `.into_iter()`, and wrap in parens if necessary
Add `crate_in_macro_def` lint
This PR adds a lint to check for `crate` as opposed to `$crate` used in a macro definition.
I think this can close#4798. That issue focused on the case where the macro author "imports something into said macro."
But I think use of `crate` is likely to be a bug whether it appears in a `use` statement or not. There could be some use case I am failing to see, though. (cc: `@nilscript` `@flip1995)`
changelog: `crate_in_macro_def`
new lint: `only_used_in_recursion`
changed:
- added `only_used_in_recursion`.
- fixed code that variables are only used in recursion.
- this would not lint when `unused_variable`
This fixes: #8390
-----
changelog: add lint [`only_used_in_recursion`]
Llint for casting between raw slice pointers with different element sizes
This lint disallows using `as` to convert from a raw pointer to a slice (e.g. `*const [i32]`, `*mut [Foo]`) to any other raw pointer to a slice if the element types have different sizes. When a raw slice pointer is cast, the data pointer and count metadata are preserved. This means that when the size of the inner slice's element type changes, the total number of bytes pointed to by the count changes. For example a `*const [i32]` with length 4 (four `i32` elements) is cast `as *const [u8]` the resulting pointer points to four `u8` elements at the same address, losing most of the data. When the size *increases* the resulting pointer will point to *more* data, and accessing that data will be UB.
On its own, *producing* the pointer isn't actually a problem, but because any use of the pointer as a slice will either produce surprising behavior or cause UB I believe this is a correctness lint. If the pointer is not intended to be used as a slice, the user should instead use any of a number of methods to produce just a data pointer including an `as` cast to a thin pointer (e.g. `p as *const i32`) or if the pointer is being created from a slice, the `as_ptr` method on slices. Detecting the intended use of the pointer is outside the scope of this lint, but I believe this lint will also lead users to realize that a slice pointer is only for slices.
There is an exception to this lint when either of the slice element types are zero sized (e.g `*mut [()]`). The total number of bytes pointed to by the slice with a zero sized element is zero. In that case preserving the length metadata is likely intended as a workaround to get the length metadata of a slice pointer though a zero sized slice.
The lint does not forbid casting pointers to slices with the *same* element size as the cast was likely intended to reinterpret the data in the slice as some equivalently sized data and the resulting pointer will behave as intended.
---
changelog: Added ``[`cast_slice_different_sizes`]``, a lint that disallows using `as`-casts to convert between raw pointers to slices when the elements have different sizes.
Only point at the end of the crate. We could try making it point at the
beginning of the crate, but that is confused with `DUMMY_SP`, causing
the output to be *worse*.
This change will make it so that VSCode will *not* underline the whole
file when `main` is missing, so other errors will be visible.
Add lint to detect `allow` attributes without reason
I was considering putting this lint into the pedantic group. However, that would result in countless warnings for existing projects. Having it in restriction also seems good to me 🙃 (And now I need sleep 💤 )
---
changelog: New lint [`allow_lint_without_reason`] (Requires the `lint_reasons` feature)
Closes: rust-lang/rust-clippy#8502
Add `unnecessary_find_map` lint
This PR adds an `unnecessary_find_map` lint. It is essentially just a minor enhancement of `unnecessary_filter_map`.
Closes#8467
changelog: New lint `unnecessary_find_map`
fix false positives of large_enum_variant
fixes: #8321
The size of enums containing generic type was calculated to be 0.
I changed [large_enum_variant] so that such enums are not linted.
changelog: none
Don't lint `match` expressions with `cfg`ed arms
Somehow there are no open issues related to this for any of the affected lints. At least none that I could fine from a quick search.
changelog: Don't lint `match` expressions with `cfg`ed arms in many cases
Fix `await_holding_lock` not linting `parking_lot` Mutex/RwLock
This adds tests for `RwLock` and `parking_lot::{Mutex, RwLock}`, which were added before in 2dc8c083f5, but never tested in UI tests. I noticed this while reading [fasterthanli.me](https://fasterthanli.me/articles/a-rust-match-made-in-hell) latest blog post, complaining that Clippy doesn't catch this for `parking_lot`. (Too many people read his blog, he's too powerful)
Some more things:
- Adds a test for #6446
- Improves the lint message
changelog: [`await_holding_lock`]: Now also lints for `parking_lot::{Mutex, RwLock}`
Improve `redundant_slicing` lint
fixes#7972fixes#7257
This can supersede #7976
changelog: Fix suggestion for `redundant_slicing` when re-borrowing for a method call
changelog: New lint `deref_as_slicing`
Don't lint `needless_borrow` in method receiver positions
fixes#8408fixes#8407fixes#8391fixes#8367fixes#8380
This is a temporary fix for `needless_borrow`. The proper fix is included in #8355.
This should probably be merged into rustc before beta branches on Friday. This issue has been reported six or seven times in the past couple of weeks.
changelog: Fix various issues with `needless_borrow` n´. Note to changelog writer: those issues might have been introduced in this release cycle, so this might not matter in the changelog.
