Rework `octal_escapes`
Main changes are not doing UTF-8 decoding, noting each occurrence as an individual lint emission, and narrowing the span to point to the escape itself.
changelog: none
Fix ICE in `upper_case_acronyms`
fixes#12284
The logic has been rewritten to avoid allocations. The old version allocated multiple vecs and strings for each identifier. The new logic allocates a single string only when the lint triggers.
This also no longer lints on strings which don't start with an uppercase letter (e.g. `something_FOO`).
changelog: none
Avoid emitting `assigning_clones` when cloned data borrows from the place to clone into
Fixes#12444Fixes#12460Fixes#12749Fixes#12757Fixes#12929
I think the documentation for the function should describe what- and how this is fixing the issues well.
It avoids emitting a warning when the data being cloned borrows from the place to clone into, which is information that we can get from `PossibleBorrowerMap`. Unfortunately, it is a tiny bit tedious to match on the MIR like that and I'm not sure if this is possibly relying a bit too much on the exact MIR lowering for assignments.
Things left to do:
- [x] Handle place projections (or verify that they work as expected)
- [x] Handle non-`Drop` types
changelog: [`assigning_clones`]: avoid warning when the suggestion would lead to a borrow-check error
When both `std::` and `core::` items are available, only suggest the
`std::` ones. We ensure that in `no_std` crates we suggest `core::`
items.
Ensure that the list of items suggested to be imported are always in the
order of local crate items, `std`/`core` items and finally foreign crate
items.
Tweak wording of import suggestion: if there are multiple items but they
are all of the same kind, we use the kind name and not the generic "items".
Fix#83564.
Let `qualify_min_const_fn` deal with drop terminators
Fixes#12677
The `method_accepts_droppable` check that was there seemed overly conservative.
> Returns true if any of the method parameters is a type that implements `Drop`.
> The method can't be made const then, because `drop` can't be const-evaluated.
Accepting parameters that implement `Drop` should still be fine as long as the parameter isn't actually dropped, as is the case in the linked issue where the droppable is moved into the return place. This more accurate analysis ("is there a `drop` terminator") is already done by `qualify_min_const_fn` [here](f5e250180c/clippy_utils/src/qualify_min_const_fn.rs (L298)), so I don't think this additional check is really necessary?
Fixing the other, second case in the linked issue was only slightly more involved, since `Vec::new()` is a function call that has the ability to panic, so there must be a `drop()` terminator for cleanup, however we should be able to freely ignore that. [Const checking ignores cleanup blocks](https://github.com/rust-lang/rust/blob/master/compiler/rustc_const_eval/src/transform/check_consts/check.rs#L382-L388), so we should, too?
r? `@Jarcho`
----
changelog: [`missing_const_for_fn`]: continue linting on fns with parameters implementing `Drop` if they're not actually dropped
Don't lint indexing_slicing lints on proc macros
This pr fixes https://github.com/rust-lang/rust-clippy/issues/12824
Even though the issue mentions the indexing case only, it was easy to apply the fix to the slicing case as well.
changelog: [`out_of_bounds_indexing`, `indexing_slicing`]: Don't lint on procedural macros.
Handle single chars with `to_string()` for `single_char_add_str`
Add support for single chars / literals with `to_string()` call for `push_str()` and `insert_str()`.
changelog: [`single_char_add_str`]: handle single chars with `to_string()` call
Closes#12775
- remove now dead code in ASSERTIONS_ON_CONSTANTS
cc #11966
- Partially revert "ignore `assertions-on-constants` in const contexts"
This reverts commit c7074de420a2192fb40d3f2194a20dd0d1b65cc6.
Don't lint blocks in closures for blocks_in_conditions
Seemed like an outlier for the lint which generally caught only the syntactically confusing cases, it lints blocks in closures but excludes closures passed to iterator methods, this changes it to ignore closures in general
changelog: none
Remove `lazy_static` mention
I planned to replace any mention with `LazyLock` but I think `thread_local` is more appropriate here - `const`s that aren't `Sync` wouldn't be able to go in a `lazy_static`/`static LazyLock` either
Also removed a test file that was mostly commented out so wasn't testing anything
changelog: none
Make `for_each_expr` visit closures by default, rename the old version `for_each_expr_without_closures`
A lot of the time `for_each_expr` is picked when closures should be visited so I think it makes sense for this to be the default with the alternative available for when you don't need to visit them.
The first commit renames `for_each_expr` to `for_each_expr_without_closures` and `for_each_expr_with_closures` to `for_each_expr`
The second commit switches a few uses that I caught over to include closures to fix a few bugs
changelog: none
Handle const effects inherited from parent correctly in `type_certainty`
This fixes a (debug) ICE in `type_certainty` that happened in the [k256 crate]. (I'm sure you can also specifically construct an edge test case that will run into type_certainty false positives visible outside of debug builds from this bug)
<details>
<summary>Minimal ICE repro</summary>
```rs
use std::ops::Add;
Add::add(1_i32, 1).add(i32::MIN);
```
</details>
The subtraction here overflowed:
436675b477/clippy_utils/src/ty/type_certainty/mod.rs (L209)
... when we have something like `Add::add` where `add` fn has 0 generic params but the `host_effect_index` is `Some(2)` (inherited from the parent generics, the const trait `Add`), and we end up executing `0 - 1`.
(Even if the own generics weren't empty and we didn't overflow, this would still be wrong because it would assume that a trait method with 1 generic parameter didn't have any generics).
So, *only* exclude the "host" generic parameter if it's actually bound by the own generics
changelog: none
[k256 crate]: https://github.com/RustCrypto/elliptic-curves/tree/master/k256
Revert: create const block bodies in typeck via query feeding
as per the discussion in https://github.com/rust-lang/rust/pull/125806#discussion_r1622563948
It was a mistake to try to shoehorn const blocks and some specific anon consts into the same box and feed them during typeck. It turned out not simplifying anything (my hope was that we could feed `type_of` to start avoiding the huge HIR matcher, but that didn't work out), but instead making a few things more fragile.
reverts the const-block-specific parts of https://github.com/rust-lang/rust/pull/124650
`@bors` rollup=never had a small perf impact previously
fixes https://github.com/rust-lang/rust/issues/125846
r? `@compiler-errors`
This commit fixes a bug introduced in #12706, where the behavior of the
lint has been changed, to avoid suggestions that introduce a move. The
motivation in the commit message is quite poor (if the detection for
significant drops is not sufficient because it's not transitive, the
proper fix would be to make it transitive). However, #12454, the linked
issue, provides a good reason for the change — if the value being
borrowed is bound to a variable, then moving it will only introduce
friction into future refactorings.
Thus #12706 changes the logic so that the lint triggers if the value
being borrowed is Copy, or is the result of a function call, simplifying
the logic to the point where analysing "is this the only use of this
value" isn't necessary.
However, said PR also introduces an undocumented carveout, where
referents that themselves are mutable references are treated as Copy,
to catch some cases that we do want to lint against. However, that is
not sound — it's possible to consume a mutable reference by moving it.
To avoid emitting false suggestions, this PR reintroduces the
referent_used_exactly_once logic and runs that check for referents that
are themselves mutable references.
Thinking about the code shape of &mut x, where x: &mut T, raises the
point that while removing the &mut outright won't work, the extra
indirection is still undesirable, and perhaps instead we should suggest
reborrowing: &mut *x. That, however, is left as possible future work.
Fixes#12856
Fix grammer for the Safety documentation check
The original message ("unsafe function's docs miss `# Safety` section") reads quite awkwardly. I've changed it to "unsafe function's docs are missing a `# Safety` section" to have it read better.
```
changelog: [`missing_headers`]: Tweak the grammar in the lint message
```
[`overly_complex_bool_expr`]: Fix trigger wrongly on never type
fixes#12689
---
changelog: fix [`overly_complex_bool_expr`] triggers wrongly on never type
Dedup nonminimal_bool_methods diags
Relates to #12379
Fix `nonminimal_bool` lint so that it doesn't check the same span multiple times.
`NotSimplificationVisitor` was called for each expression from `NonminimalBoolVisitor` whereas `NotSimplificationVisitor` also recursively checked all expressions.
---
changelog: [`nonminimal_bool`]: Fix duplicate diagnostics
The original message ("unsafe function's docs miss `# Safety` section")
reads quite awkwardly. I've changed it to "unsafe function's docs are missing
a `# Safety` section" to have it read better.
Signed-off-by: Paul R. Tagliamonte <paultag@gmail.com>
Modify str_to_string to be machine-applicable
Fixes https://github.com/rust-lang/rust-clippy/issues/12768
I'm not sure if there is any potential for edge cases with this - since it only ever acts on `&str` types I can't think of any, and especially since the methods do the same thing anyway.
changelog: allow `str_to_string` lint to be automatically applied
Disable `indexing_slicing` for custom Index impls
Fixes https://github.com/rust-lang/rust-clippy/issues/11525
Disables `indexing_slicing` for custom Index impls, specifically any implementations that also do not have a `get` method anywhere along the deref chain (so, for example, it still lints on Vec, which has its `get` method as part of the deref chain).
Thanks `@y21` for pointing me in the right direction with a couple of handy util functions for deref chain and inherent methods, saved a headache there!
changelog: FP: Disable `indexing_slicing` for custom Index impls
fix: let non_canonical_impls skip proc marco
Fixed#12788
Although the issue only mentions `NON_CANONICAL_CLONE_IMPL`, this fix will also affect `NON_CANONICAL_PARTIAL_ORD_IMPL` because I saw
> Because of these unforeseeable or unstable behaviors, macro expansion should often not be regarded as a part of the stable API.
on Clippy Documentation and these two lints are similar, so I think it might be good, not sure if it's right or not.
---
changelog: `NON_CANONICAL_CLONE_IMPL`, `NON_CANONICAL_PARTIAL_ORD_IMPL` will skip proc marco now
[`many_single_char_names`]: Deduplicate diagnostics
Relates to #12379
Fix `many_single_char_names` lint so that it doesn't emit diagnostics when the current level of the scope doesn't contain any single character name.
```rust
let (a, b, c, d): (i32, i32, i32, i32);
match 1 {
1 => (),
e => {},
}
```
produced the exact same MANY_SINGLE_CHAR_NAMES diagnostic at each of the Arm `e => {}` and the Block `{}`.
---
changelog: [`many_single_char_names`]: Fix duplicate diagnostics
Fix `unnecessary_to_owned` interaction with macro expansion
fixes#12821
In the case of an unnecessary `.iter().cloned()`, the lint `unnecessary_to_owned` might suggest to remove the `&` from references without checking if such references are inside a macro expansion. This can lead to unexpected behavior or even broken code if the lint suggestion is applied blindly. See issue #12821 for an example.
This PR checks if such references are inside macro expansions and skips this part of the lint suggestion in these cases.
changelog: [`unnecessary_to_owned`]: Don't suggest to remove `&` inside macro expansion
[perf] Delay the construction of early lint diag structs
Attacks some of the perf regressions from https://github.com/rust-lang/rust/pull/124417#issuecomment-2123700666.
See individual commits for details. The first three commits are not strictly necessary.
However, the 2nd one (06bc4fc67145e3a7be9b5a2cf2b5968cef36e587, *Remove `LintDiagnostic::msg`*) makes the main change way nicer to implement.
It's also pretty sweet on its own if I may say so myself.
`significant_drop_in_scrutinee`: Trigger lint only if lifetime allows early significant drop
I want to argue that the following code snippet should not trigger `significant_drop_in_scrutinee` (https://github.com/rust-lang/rust-clippy/issues/8987). The iterator holds a reference to the locked data, so it is expected that the mutex guard must be alive until the entire loop is finished.
```rust
use std::sync::Mutex;
fn main() {
let mutex_vec = Mutex::new(vec![1, 2, 3]);
for number in mutex_vec.lock().unwrap().iter() {
dbg!(number);
}
}
```
However, the lint should be triggered when we clone the vector. In this case, the iterator does not hold any reference to the locked data.
```diff
- for number in mutex_vec.lock().unwrap().iter() {
+ for number in mutex_vec.lock().unwrap().clone().iter() {
```
Unfortunately, it seems that regions on the types of local variables are mostly erased (`ReErased`) in the late lint pass. So it is hard to tell if the final expression has a lifetime relevant to the value with a significant drop.
In this PR, I try to make a best-effort guess based on the function signatures. To avoid false positives, no lint is issued if the result is uncertain. I'm not sure if this is acceptable or not, so any comments are welcome.
Fixes https://github.com/rust-lang/rust-clippy/issues/8987
changelog: [`significant_drop_in_scrutinee`]: Trigger lint only if lifetime allows early significant drop.
r? `@flip1995`
* instead simply set the primary message inside the lint decorator functions
* it used to be this way before [#]101986 which introduced `msg` to prevent
good path delayed bugs (which no longer exist) from firing under certain
circumstances when lints were suppressed / silenced
* this is no longer necessary for various reasons I presume
* it shaves off complexity and makes further changes easier to implement
fulfill expectations in `check_unsafe_derive_deserialize`
The utility function `clippy_utils::fulfill_or_allowed` is not used because using it would require to move the check for allowed after the check iterating over all inherent impls of the type, doing possibly unnecessary work.
Instead, `is_lint_allowed` is called as before, but additionally, once certain that the lint should be emitted, `span_lint_hir_and_then` is called instead of `span_lint_and_help` to also fulfill expectations.
Note: as this is my first contribution, please feel free to nitpick or request changes. I am happy to adjust the implementation.
fixes: #12802
changelog: fulfill expectations in [`unsafe_derive_deserialize`]
Add new lint `while_float`
This PR adds a nursery lint that checks for while loops comparing floating point values.
changelog:
```
changelog: [`while_float`]: Checks for while loops comparing floating point values.
```
Fixes#758
This avoids event spans that would otherwise cause crashes, since an
End's span covers the range of the tag (which will be earlier than the
line break within the tag).
Add configuration option for ignoring `panic!()` in tests
```
changelog: [`panic`]: Now can be disabled in tests with the `allow-panic-in-tests` option
```
I often find myself using `panic!(…)` in tests a lot, where I often do something like:
```rust
match enam {
Enam::A => …,
Enam::B => …,
_ => panic!("This should not happen at all."),
}
```
I think this patch should go nicely with already existing `allow-unwrap-in-tests` and `allow-expect-in-tests`.
make sure the msrv for `const_raw_ptr_deref` is met when linting [`missing_const_for_fn`]
fixes: #8864
---
changelog: make sure the msrv for `const_ptr_deref` is met when linting [`missing_const_for_fn`]
less aggressive needless_borrows_for_generic_args
Current implementation looks for significant drops, that can change the behavior, but that's not enough - value might not have a `Drop` itself but one of its children might have it.
A good example is passing a reference to `PathBuf` to `std::fs::File::open`. There's no benefits to pass `PathBuf` by value, but since `clippy` can't see `Drop` on `Vec` several layers down it complains forcing pass by value and making it impossible to use the same name later.
New implementation only looks at copy values or values created in place so existing variable will never be moved but things that take a string reference created and value is created inplace `&"".to_owned()` will make it to suggest to use `"".to_owned()` still.
Fixes https://github.com/rust-lang/rust-clippy/issues/12454
changelog: [`needless_borrows_for_generic_args`]: avoid moving variables
improve [`match_same_arms`] messages, enable rustfix test
closes: #9251
don't worry about the commit size, most of them are generated
---
changelog: improve [`match_same_arms`] lint messages
`significant_drop_in_scrutinee`: Fix false positives due to false drops of place expressions
Place expressions do not really create temporaries, so they will not create significant drops. For example, the following code snippet is quite good (#8963):
```rust
fn main() {
let x = std::sync::Mutex::new(vec![1, 2, 3]);
let x_guard = x.lock().unwrap();
match x_guard[0] {
1 => println!("1!"),
x => println!("{x}"),
}
drop(x_guard); // Some "usage"
}
```
Also, the previous logic thinks that references like `&MutexGuard<_>`/`Ref<'_, MutexGuard<'_, _>>` have significant drops, which is simply not true, so it is fixed together in this PR.
Fixes https://github.com/rust-lang/rust-clippy/issues/8963
Fixes https://github.com/rust-lang/rust-clippy/issues/9072
changelog: [`significant_drop_in_scrutinee`]: Fix false positives due to false drops of place expressions.
r? `@blyxyas`
add new lint that disallow renaming parameters in trait functions
fixes: #11443fixes: #486
changelog: add new lint [`renamed_function_params`]
Note that the lint name is not final, because I have a bad reputation in naming things, and I don't trust myself.
Lint direct priority conflicts in `[workspace.lints]`
Partially addresses #12729
This still doesn't do any workspace resolution stuff, so it will not catch any virtual workspaces or conflicts from inherited definitions. But while we're parsing the `Cargo.toml` we might as well check the workspace definitions if we find them
changelog: none
Handle `rustc_on_unimplemented` in duplicated_attributes
```rust
#[rustc_on_unimplemented(
on(
_Self = "&str",
label = "`a"
),
on(
_Self = "alloc::string::String",
label = "a"
),
)]
```
The lint treats this as a repetition because `rustc_on_unimplemented:🔛:label` appears twice, but that's ok.
Fixes#12619
changelog: [`duplicated_attributes`]: fix handling of `rustc_on_unimplemented`
Add new lint `doc_lazy_continuation`
changelog: [`doc_lazy_continuation`]: add lint that warns on so-called "lazy paragraph continuations"
This is a follow-up for https://github.com/rust-lang/rust/pull/121659, since most cases of unintended block quotes are lazy continuations. The lint is designed to be more generally useful than that, though, because it will also catch unintended list items and unintended block quotes that didn't coincidentally hit a pulldown-cmark bug.
The second commit is the result of running `cargo dev dogfood --fix`, and manually fixing anything that seems wrong. NOTE: this lint's suggestions should never change the parser's interpretation of the markdown, but in many cases, it seems that doc comments in clippy were written without regard for this feature of Markdown (which, I suppose, is why this lint should exist).
fix: use hir_with_context to produce correct snippets for assigning_clones
The `assigning_clones` lint is producing wrong output when the assignment is a macro call.
Since Applicability level `Unspecified` will never be changed inside `hir_with_applicability`, so it is safe here to replace `hir_with_applicability` with `hir_with_context` to generate snippets of the macro call instead of the expansion.
fixes#12776
changelog: [`assigning_clones`]: use `hir_with_context` to produce correct snippets
fix false positive in Issue/12098 because lack of consideration of mutable caller
fixes [Issue#12098](https://github.com/rust-lang/rust-clippy/issues/12098)
In issue#12098, the former code doesn't consider the caller for clone is mutable, and suggests to delete clone function.
In this change, we first get the inner caller requests for clone,
and if it's immutable, the following code will suggest deleting clone.
If it's mutable, the loop will check whether a borrow check violation exists,
if exists, the lint should not execute, and the function will directly return;
otherwise, the following code will handle this.
changelog: [`clippy::unnecessary_to_owned`]: fix false positive
This is a follow-up for https://github.com/rust-lang/rust/pull/121659,
since most cases of unintended block quotes are lazy continuations.
The lint is designed to be more generally useful than that, though,
because it will also catch unintended list items and unintended
block quotes that didn't coincidentally hit a pulldown-cmark bug.
Allow more attributes in `clippy::useless_attribute`
Fixes#12753Fixes#4467Fixes#11595Fixes#10878
changelog: [`useless_attribute`]: Attributes allowed on `use` items now include `ambiguous_glob_exports`, `hidden_glob_reexports`, `dead_code`, `unused_braces`, and `clippy::disallowed_types`.
Current implementation looks for significant drops, that can change the
behavior, but that's not enough - value might not have a Drop itself but
one of its children might have it.
A good example is passing a reference to `PathBuf` to `std::fs::File::open`.
There's no benefits to pass `PathBuf` by value, but since clippy can't
see `Drop` on `Vec` several layers down it complains forcing pass by
value and making it impossible to use the same name later.
New implementation only looks at copy values or values created inplace
so existing variable will never be moved but things that take a string
reference created and value is created inplace `&"".to_owned()` will
make it to suggest to use `"".to_owned()` still.
Fixes https://github.com/rust-lang/rust-clippy/issues/12454
Suggest collapsing nested or patterns if the MSRV allows it
Nested `or` patterns have been stable since 1.53, so we should be able to suggest `Some(1 | 2)` if the MSRV isn't set below that.
This change adds an msrv check and also moves it to `matches/mod.rs`, because it's also needed by `redundant_guards`.
changelog: [`collapsible_match`]: suggest collapsing nested or patterns if the MSRV allows it
fix suggestion error for [`manual_is_ascii_check`] with missing type
fixes: #11324fixes: #11776
changelog: improve [`manual_is_ascii_check`] to suggest labeling type in closure, fix FP with type generics, and improve linting on ref expressions.
suppress `readonly_write_lock` for underscore-prefixed bindings
Fixes#12733
Unsure if there's a better way to prevent this kind of false positive but this is the one that made most sense to me.
In my experience, prefixing bindings with an underscore is the usual way to name variables that aren't used and that exist purely for executing drop code at the end of the scope.
-------
changelog: suppress [`readonly_write_lock`] for underscore-prefixed bindings
check if closure as method arg has read access in [`collection_is_never_read`]
fixes: #11783
---
changelog: fix [`collection_is_never_read`] misfires when use `retain` for iteration
configurably allow `useless_vec` in tests
This adds a `àllow-useless-vec-in-test` configuration which, when set to `true` will allow the `useless_vec` lint in `#[test]` functions and code within `#[cfg(test)]`. It also moves a `is_in_test` helper to `clippy_utils`.
---
changelog: configurably allow [`useless_vec`] in test code
This adds a `àllow-useless-vec-in-test` configuration which, when set
to `true` will allow the `useless_vec` lint in `#[test]` functions and
code within `#[cfg(test)]`. It also moves a `is_in_test` helper to
`clippy_utils`.
fix [`large_stack_arrays`] linting in `vec` macro
fixes: #12586
this PR also adds a wrapper function `matching_root_macro_call` to `clippy_utils::macros`, considering how often that same pattern appears in the codebase.
(I'm always very indecisive towards naming, so, if anyone have better idea of how that function should be named, feel free to suggest it)
---
changelog: fix [`large_stack_arrays`] linting in `vec` macro; add `matching_root_macro_call` to clippy_utils
[`non_canonical_partial_ord_impl`]: Fix emitting warnings which conflict with `needless_return`
fixes#12683
---
changelog: fix [`non_canonical_partial_ord_impl`] emitting warnings which conflict with `needless_return`
Disallow ambiguous attributes on expressions
This implements the suggestion in [#15701](https://github.com/rust-lang/rust/issues/15701#issuecomment-2033124217) to disallow ambiguous outer attributes on expressions. This should resolve one of the concerns blocking the stabilization of `stmt_expr_attributes`.
reduce `single_char_pattern` to only lint on ascii chars
This should mostly fix the `single_char_pattern` lint, because with a single byte, the optimizer will usually see through the char-to-string-expansion and single loop iteration. This fixes#11675 and #8111.
Update: As per the meeting on November 28th, 2023, we voted to also downgrade the lint to pedantic.
---
changelog: downgrade [`single_char_pattern`] to `pedantic`
Fix `is_test_module_or_function`
The rustdoc comment for `is_test_module_or_function` states: 2795a60189/clippy_utils/src/lib.rs (L2561-L2566)
Given `item`, the function calls `is_in_test_function` with `item.hir_id()`. However, `is_in_test_function` considers only `item`'s parents, not `item` itself. This PR fixes the problem.
The `test_with_disallowed_name` test fails without the fix, but passes once applied.
changelog: none
Rework interior mutability detection
Replaces the existing interior mutability detection, the two main changes being
- It now follows references/pointers e.g. `struct S(&Cell)`
- `mutable_key_type` ignores pointers as it did before
- The `ignore_interior_mutability` config now applies to types containing the ignored type, e.g. `http::HeaderName`
Fixes https://github.com/rust-lang/rust-clippy/issues/7752
Fixes https://github.com/rust-lang/rust-clippy/issues/9776
Fixes https://github.com/rust-lang/rust-clippy/issues/9801
changelog: [`mutable_key_type`], [`declare_interior_mutable_const`]: now considers types that have references to interior mutable types as interior mutable
This commit introduces a check to ensure that the lint won't trigger when the initializer is
unreachable, such as:
```
thread_local! {
static STATE: Cell<usize> = panic!();
}
```
This is achieved by looking at the unpeeled initializer expression and ensuring that the parent
macro is not `panic!()`, `todo!()`, `unreachable!()`, `unimplemented!()`.
fixes#12637
changelog: [`threadlocal_initializer_can_be_made_const`] will no longer trigger on `unreachable` macros.
