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.
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`
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`
The to_string_in_display lint is renamed to recursive_format_impl
A check is added for the use of self formatted with Display or Debug
inside any format string in the same impl
The to_string_in_display check is kept as is - like in the
format_in_format_args lint
For now only Display and Debug are checked
This could also be extended to other Format traits (Binary, etc.)
Add lint `transmute_undefined_repr`
Partially implements #3999 and #546
This doesn't consider `enum`s at all right now as those are going to be a pain to deal with. This also allows `#[repr(Rust)]` structs with only one non-zero sized fields. I think those are technically undefined when transmuted.
changelog: Add lint `transmute_undefined_repr`
This pull request adds a lint against single character lifetime names, as they might not divulge enough information about the purpose of the lifetime. This can make code harder to understand. I placed this in `restriction` rather than `pedantic` (as suggested in #8233) since most of the Rust ecosystem already uses single character lifetime names (to my knowledge, at least) and since single character lifetime names aren't incorrect. I'd be happy to change this upon request, however. Fixes#8233.
- [x] Followed lint naming conventions
- [x] Added passing UI tests (including committed `.stderr` file)
- [x] `cargo test` passes locally
- [x] Executed `cargo dev update_lints`
- [x] Added lint documentation
- [x] Run `cargo dev fmt`
changelog: new lint: [`single_char_lifetime_names`]
This checks for sequences in strings that would be octal character
escapes in C, but are not supported in Rust. It suggests either
to use the `\x00` escape, or an equivalent hex escape if the octal
was intended.
Fix for #7889 and add new lint needless_splitn
fixes: #7889
1. Fix the problem of manual_split_once changing the original behavior.
2. Add a new lint needless_splitn.
changelog: Fix the problem of manual_split_once changing the original behavior and add a new lint needless_splitn.
1. Fix the problem of manual_split_once changing the original behavior.
2. Add a new lint needless_splitn.
changelog: Fix the problem of manual_split_once changing the original behavior and add a new lint needless_splitn.
* Finding pattern slices for `avoidable_slice_indexing`
* `avoidable_slice_indexing` analysing slice usage
* Add configuration to `avoidable_slice_indexing`
* Emitting `avoidable_slice_indexing` with suggestions
* Dogfooding and fixing bugs
* Add ui-toml test for `avoidable_slice_indexing`
* Correctly suggest `ref` keywords for `avoidable_slice_indexing`
* Test and document `mut` for `avoid_slice_indexing`
* Handle macros with `avoidable_slice_indexing` lint
* Ignore slices with sub patterns in `avoidable_slice_indexing`
* Update lint description for `avoidable_slice_indexing`
* Move `avoidable_slice_indexing` to nursery
* Added more tests for `avoidable_slice_indexing`
* Update documentation and message for `avoidable_slice_indexing`
* Teach `avoidable_slice_indexing` about `HirId`s and `Visitors`
* Rename lint to `index_refutable_slice` and connected config
Unseparated literal suffix
Closes#7658
Since `literal_suffix` style is opinionated, we should disable by default and only enforce if it's stated as so.
changelog: [`unseparated_literal_suffix`] is renamed to `literal_suffix`, adds a new configuration `literal-suffix-style` to enforce a certain style writing literal_suffix. Possible values for `literal-suffix-style`: `"separated"`, `"unseparated"`
Add unit-hash lint
changelog: [`unit_hash`] Add lint for hashing unit values
This will lint for situations where the end user is attempting to hash a unit value (`()`), as the implementation in `std` simply [does nothing][impl]. Closes#7159 .
Example:
```rust
().hash(&mut state);
// Should (probably) be replaced with:
0_u8.hash(&mut state);
```
[impl]: a5f164faad/library/core/src/hash/mod.rs (L656)
new lint: string-slice
This is a restriction lint to highlight code that should have tests containing non-ascii characters. See #6623.
changelog: new lint: [`string-slice`]
Warn on structs with a trailing zero-sized array but no `repr` attribute
Closes#2868
changelog: Implement ``[`trailing_empty_array`]``, which warns if a struct is defined where the last field is a zero-sized array but there are no `repr` attributes. Zero-sized arrays aren't very useful in Rust itself, so such a struct is likely being created to pass to C code or in some other situation where control over memory layout matters. Either way, a `repr` attribute is needed.
Add module_style lint to style
changelog: Add new [`module_style`] style lint
This is a configurable (no mod file/mod file) lint that determines if `mod.rs` is used consistently or if `mod.rs` is never used (using the new mod layout).
Add tests for disallowed_mod in ui-cargo test section
Use correct algorithm to determine if mod.rs is missing
Move to two lints and remove config option
Switch lint names so they read "warn on ..."
Emit the same help info for self_named_mod_file warnings
Bail when both lints are Allow
Reword help message for both module_style lints
Add new lint `negative_feature_names` and `redundant_feature_names`
Add new lint [`negative_feature_names`] to detect feature names with prefixes `no-` or `not-` and new lint [`redundant_feature_names`] to detect feature names with prefixes `use-`, `with-` or suffix `-support`
changelog: Add new lint [`negative_feature_names`] and [`redundant_feature_names`]
New lint: [`self_named_constructor`]
Adds the `self_named_constructor` lint for detecting when an implemented method has the same name as the type it is implemented for.
changelog: [`self_named_constructor`]
closes: #7142
Add macro_braces lint to check for irregular brace use in certain macros
The name is a bit long but this sounds good as `#[allow(unconventional_macro_braces)]` and it seems more clear that we are talking about the macro call not macro definitions, any feedback let me know. Thanks!
fixes#7278
changelog: Add ``[`unconventional_macro_braces`]`` lint that checks for uncommon brace usage with macros.
Rename unconventional -> nonstandard, add config field
Add standard_macro_braces fields so users can specify macro names and
brace combinations to lint for in the clippy.toml file.
Fix errors caused by nonstandard_macro_braces in other lint tests
Fix users ability to override the default nonstandard macro braces
Add type position macros impl `check_ty`
Add `needless_bitwise_bool` lint
fixes#6827fixes#1594
changelog: Add ``[`needless_bitwise_bool`]`` lint
Creates a new `bitwise_bool` lint to convert `x & y` to `x && y` when both `x` and `y` are booleans. I also had to adjust thh `needless_bool` lint slightly, and fix a couple failing dogfood tests. I made it a correctness lint as per flip1995's comment [here](https://github.com/rust-lang/rust-clippy/pull/3385#issuecomment-434715723), from a previous WIP attempt at this lint.
New lint: `unused_async`
changelog: Adds a lint, `unused_async`, which checks for async functions with no await statements
`unused_async` is a lint that reduces code smell and overhead by encouraging async functions to be refactored into synchronous functions.
Fixes#7176
### Examples
```rust
async fn get_random_number() -> i64 {
4 // Chosen by fair dice roll. Guaranteed to be random.
}
```
Could be written as:
```rust
fn get_random_number() -> i64 {
4 // Chosen by fair dice roll. Guaranteed to be random.
}
```
Something like this, however, should **not** be caught by clippy:
```rust
#[async_trait]
trait AsyncTrait {
async fn foo();
}
struct Bar;
#[async_trait]
impl AsyncTrait for Bar {
async fn foo() {
println!("bar");
}
}
```
The most recent changelog update 037ddf282b accompanying the 1.52 release added a second "Rust 1.52" section header, with the result that the Rust release announcement https://blog.rust-lang.org/2021/05/06/Rust-1.52.0.html is linking to the "current beta" changelog section for Clippy rather than the stable changelog. I don't know the release process but based on previous changes to this file, I assume the correct thing to do is to mark the topmost section as being for Rust 1.53, not 1.52.
Add lint to check for boolean comparison in assert macro calls
This PR adds a lint to check if an assert macro is using a boolean as "comparison value". For example:
```rust
assert_eq!("a".is_empty(), false);
```
Could be rewritten as:
```rust
assert!(!"a".is_empty());
```
PS: The dev guidelines are amazing. Thanks a lot for writing them!
changelog: Add `bool_assert_comparison` lint
* Added expression check for shared_code_in_if_blocks
* Finishing touches for the shared_code_in_if_blocks lint
* Applying PR suggestions
* Update lints yay
* Moved test into subfolder
Lint: filter(Option::is_some).map(Option::unwrap)
Fixes#6061
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog:
* add new lint for filter(Option::is_some).map(Option::unwrap)
First Rust PR, so I'm sure I've violated some idioms. Happy to change anything.
I'm getting one test failure locally -- a stderr diff for `compile_test`. I'm having a hard time seeing how I could be causing it, so I'm tentatively opening this in the hopes that it's an artifact of my local setup against `rustc`. Hoping it can at least still be reviewed in the meantime.
I'm gathering that since this is a method lint, and `.filter(...).map(...)` is already checked, the means of implementation needs to be a little different, so I didn't exactly follow the setup boilerplate. My way of checking for method calls seems a little too direct (ie, "is the second element of the expression literally the path for `Option::is_some`?"), but it seems like that's how some other lints work, so I went with it. I'm assuming we're not concerned about, eg, closures that just end up equivalent to `Option::is_some` by eta reduction.
Add the from_str_radix_10 lint
changelog: added the new `from_str_radix_10` which sometimes replaces calls to `primitive::from_str_radix` to `str::parse`
This is ready to be merged, although maybe the category should be `pedantic` instead of `style`? I'm not sure where it fits better.
Closes#6713.
New lint: default_numeric_fallback
fixes#6064
r? `@flip1995`
As we discussed in [here](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/Issue.20.236064/near/224647188) and [here](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/Issue.20clippy.236064/near/224746333), I start implementing this lint from the strictest version.
In this PR, I'll allow the below two cases to pass the lint to reduce FPs.
1. Appearances of unsuffixed numeric literals in `Local` if `Local` has a type annotation, for example:
```rust
// Good.
let x: i32 = 1;
// Also good.
let x: (i32, i32) = if cond {
(1, 2)
} else {
(2, 3)
};
```
2. Appearances of unsuffixed numeric literals in args of `Call` or `MethodCall` if corresponding arguments of their signature have concrete types, for example:
```rust
fn foo_mono(x: i32) -> i32 {
x
}
fn foo_poly<T>(t: T) -> t {
t
}
// Good.
let x = foo_mono(13);
// Still bad.
let x: i32 = foo_poly(13);
```
changelog: Added restriction lint: `default_numeric_fallback`
Add new lint `filter_map_identity`
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If you added a new lint, here's a checklist for things that will be
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- \[x] Followed [lint naming conventions][lint_naming]
- \[x] Added passing UI tests (including committed `.stderr` file)
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- \[x] Executed `cargo dev update_lints`
- \[x] Added lint documentation
- \[x] Run `cargo dev fmt`
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This commit adds a new lint named filter_map_identity.
This lint is the same as `flat_map_identity` except that it checks for the usage of `filter_map`.
---
Closes#6643
changelog: Added a new lint: `filter_map_identity`
This commit adds a new lint named `filter_map_identity`. This lint is
the same as `flat_map_identity` except that it checks for `filter_map`.
Closes#6643
New Lint: Manual Flatten
This is a draft PR for [Issue 6564](https://github.com/rust-lang/rust-clippy/issues/6564).
r? `@camsteffen`
- \[x] Followed [lint naming conventions][lint_naming]
- \[x] Added passing UI tests (including committed `.stderr` file)
- \[x] `cargo test` passes locally
- \[x] Executed `cargo dev update_lints`
- \[x] Added lint documentation
- \[x] Run `cargo dev fmt`
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: Add new lint [`manual_flatten`] to check for loops over a single `if let` expression with `Result` or `Option`.
New Lint: inspect_then_for_each
**Work In Progress**
This PR addresses [Issue 5209](https://github.com/rust-lang/rust-clippy/issues/5209) and adds a new lint called `inspect_then_for_each`.
Current seek some guidance.
If you added a new lint, here's a checklist for things that will be
checked during review or continuous integration.
- \[x] Followed [lint naming conventions][lint_naming]
- \[x] Added passing UI tests (including committed `.stderr` file)
- \[x] `cargo test` passes locally
- \[x] Executed `cargo dev update_lints`
- \[x] Added lint documentation
- \[x] Run `cargo dev fmt`
[lint_naming]: https://rust-lang.github.io/rfcs/0344-conventions-galore.html#lints
---
changelog: Add [`inspect_for_each`] lint for the use of `inspect().for_each()` on `Iterators`.
New lint: vec_init_then_push
fixes: #1483
This will trigger on `new`, `default`, and `with_capacity` when the given capacity is less than or equal to the number of push calls. Is there anything else this should trigger on?
changelog: Added lint: `vec_init_then_push`
This splits up clippy::collapsible_if into collapsible_if for
if x {
if y { }
}
=>
if x && y { }
and collapsible_else_if for
if x {
} else {
if y { }
}
=>
if x {
} else if y {
}
so that we can lint for only the latter but not the first if we desire.
changelog: collapsible_if: split up linting for if x {} else { if y {} } into collapsible_else_if lint
Add lint print_stderr
Resolves#6348
Almost identical to print_stdout, this lint applies to the `eprintln!` and `eprint!` macros rather than `println!` and `print!`.
changelog: Add new lint [`print_stderr`]. [`println_empty_string`] and [`print_with_newline`] now apply to `eprint!()` and `eprintln!()` respectively.
Also fix review comments:
- Use const arrays and iterate them for the method/function names
- merge 2 if_chain's into one using a rest pattern
- remove unnecessary unsafe block in test
And make the lint only point to the count expression instead of the entire function call
run `cargo dev new_lint --category correctness --name suspicious_chained_operators --pass early`
add (currently failing) tests for suspicious_chained_operators
add some tests to answer a question that came up during implementation
write usage code for functions we'll need to find or create
Complete left-right tracking TODO
get it compiling with several `todo!` invocations.
refactor to a set of incomplete functions that don't expect to be able to edit a `Span`
create placeholder for `suggestion_with_swapped_ident` function and correct some comments
add `inside_larger_boolean_expression` test
fill out `get_ident` and `suggestion_with_swapped_ident`
Implementi the `IdentIter`
start on implementing the `IdentIter`
handle the `ExprKind::Path` case in `IdentIter`
on second thought, make the iterator type dynamic so we don't need an explicit type for each one we will need
handle `ExprKind::MacCall` in `IdentIter`
Try handling `box x` expressions
restructure `IdentIter`
set `self.done` when returning `None`
Handle `ExprKind::Array`
reduce duplication with a macro that we expect to use several more times
handle ExprKind::Call
add `new_p` convenience method
handle `MethodCall`
handle `Tup` and `Binary`
handle `Unary`
simplify by not returning an additional `Expr` from the `IdentIter`
add cross product test against false positives
rename suspicious_chained_operators to suspicious_operation_groupings within files
For the record, the exact commands run were:
find . -type f -name "*.md" -exec sed -i 's/suspicious_chained_operators/suspicious_operation_groupings/g' {} +
find . -type f -name "*.rs" -exec sed -i 's/suspicious_chained_operators/suspicious_operation_groupings/g' {} +
find . -type f -name "*.rs" -exec sed -i 's/SUSPICIOUS_CHAINED_OPERATORS/SUSPICIOUS_OPERATION_GROUPINGS/g' {} +
find . -type f -name "*.rs" -exec sed -i 's/SuspiciousChainedOperators/SuspiciousOperationGroupings/g' {} +
Also:
rename file to match module name
rename test file to match lint name
start implementing `IdentDifference` creation
add `IdentIter` utility
use `ident_iter::IdentIter`
fix bug in `suggestion_with_swapped_ident`
add `inside_if_statements` test
implement `Add` `todo`s
register `SuspiciousOperationGroupings` lint pass
fill in `chained_binops`, and fill in a stopgap version of `ident_difference_expr`, but then notice that the lint does not seem to ever be run in the tests
run `cargo dev update_lints` and not that the `suspicious_operation_groupings` lint still does not seem to be run
fix base index incrementing bug
fix paired_identifiers bug, and remove ident from `Single`
change help prefix and note our first successful lint messages!
add odd_number_of_pairs test
get the `non_boolean_operators` test passing, with two copies of the error message
extract `is_useless_with_eq_exprs` so we can know when `eq_op` will already handle something
add `not_caught_by_eq_op` tests since `s1.b * s1.b` was (reasonably) not caught by `eq_op`
cover the case where the change should be made on either side of the expression with `not_caught_by_eq_op` tests
produce the expected suggestion on the `not_caught_by_eq_op_middle_change_left` test
confirm that the previous tests still pass and update references
fix early continue bug and get `not_caught_by_eq_op_middle_change_right` passing
note that `not_caught_by_eq_op_start` already passes
fix bugs based on misunderstanding of what `Iterator::skip` does, and note that `not_caught_by_eq_op_end` now passes
add several parens tests and make some of them pass
handle parens inside `chained_binops_helper` and note that this makes several tests pass
get `inside_larger_boolean_expression_with_unsorted_ops` test passing by extracting out `check_same_op_binops` function
also run `cargo dev fmt`
note that `inside_function_call` already passes
add another `if_statement` test
remove the matching op requirement, making `inside_larger_boolean_expression_with_unsorted_ops` pass
prevent non-change suggestions from being emitted
get the `Nested` tests passing, and remove apparently false note about eq_op
add a test to justify comment in `ident_difference_expr_with_base_location` but find that the failure mode seems different than expected
complete `todo` making `do_not_give_bad_suggestions_for_this_unusual_expr` pass and add some more tests that already pass
add test to `eq_op`
note that `inside_fn_with_similar_expression` already passes
fix `inside_an_if_statement` and note that it already passes
attempt to implement if statement extraction and notice that we don't seem to handle unary ops correctly
add `maximum_unary_minus_right_tree` test and make it pass
add two tests and note one of them passes
filter out unary operations in several places, and find that the issue seems to be that we don't currently recognize the error in `multiple_comparison_types_and_unary_minus` even so.
remove filtering that was causing bad suggestions
remove tests that were deemed too much for now
run `cargo dev fmt`
correct eq_op post-merge
fill out the description and delete debugging code
run `cargo dev update_lints`
update eq_op references
add parens to work around rustfmt issue #3666 and run rustfmt
https://github.com/rust-lang/rustfmt/issues/3666#issuecomment-714612257
update references after formatting
fix dogfood issues
fix multi-cursor edit
fix missed dogfood error
fix more dogfood pedantic issues, including function length
even more nesting
insert hidden definition of Vec3 so docs compile
add spaces to second struct def
reword test description comment
Co-authored-by: llogiq <bogusandre@gmail.com>
add local `use BinOpKind::*;`
Apply suggestions from code review
Co-authored-by: llogiq <bogusandre@gmail.com>
switch `SUSPICIOUS_OPERATION_GROUPINGS` to a style lint
run `cargo dev update_lints`
put both usages of `op_types` in the same closure to satisfy `borrowck`
fix compile error
Check when `from_utf8` is called from sliced byte array from string
---
*Please keep the line below*
changelog: Fix#5487: Add linter to check when `from_utf8` is called from sliced byte array from string.
Add lint for 'field_reassign_with_default` #568
changelog: Add lint for field_reassign_with_default that checks if mutable object + field modification is used to edit a binding initialized with Default::default() instead of struct constructor.
Fixes#568
Notes:
- Checks for reassignment of one or more fields of a binding initialized with Default::default().
- Implemented using EarlyLintPass, might be future proofed better with LateLintPass.
- Does not trigger if Default::default() is used via another type implementing Default.
- This is a re-open of [PR#4761](https://github.com/rust-lang/rust-clippy/pull/4761), but I couldn't figure out how to re-open that one so here's a new one with the requested changes :S
Add lint 'ref_option_ref' #1377
This lint checks for usage of `&Option<&T>` which can be simplified as `Option<&T>` as suggested in #1377.
This WIP PR is here to get feedback on the lint as there's more cases to be handled:
* statics/consts,
* associated types,
* type alias,
* function/method parameter/return,
* ADT definitions (struct/tuple struct fields, enum variants)
changelog: Add 'ref_option_ref' lint
Add lint: from_iter_instead_of_collect
Fixes#5679
This implements lint for `::from_iter()` from #5679 not the general issue (`std::ops::Add::add`, etc.).
This lint checks if expression is function call with `from_iter` name and if it's implementation of the `std::iter::FromIterator` trait.
changelog: Introduce from_iter_instead_of_collect lint
- Implement `field_reassign_with_default` as a `LateLintPass`
- Avoid triggering `default_trait_access` on a span already linted by
`field_reassigned_with_default`
- Merge `default_trait_access` and `field_reassign_with_default` into
`Default`
- Co-authored-by: Eduardo Broto <ebroto@tutanota.com>
- Fixes#568
Add lint for comparing to empty slices instead of using .is_empty()
Hey first time making a clippy lint
I added the implementation of the lint the `len_zero` since it shared a lot of the code, I would otherwise have to rewrite. Just tell me if the lint should use it's own file instead
changelog: Add lint for comparing to empty slices
Fixes#6217
