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`
<!-- Thank you for making Clippy better!
We're collecting our changelog from pull request descriptions.
If your PR only includes internal changes, you can just write
`changelog: none`. Otherwise, please write a short comment
explaining your change. Also, it's helpful for us that
the lint name is put into brackets `[]` and backticks `` ` ` ``,
e.g. ``[`lint_name`]``.
If your PR fixes an issue, you can add "fixes #issue_number" into this
PR description. This way the issue will be automatically closed when
your PR is merged.
If you added a new lint, here's a checklist for things that will be
checked during review or continuous integration.
- \[ ] Followed [lint naming conventions][lint_naming]
- \[ ] Added passing UI tests (including committed `.stderr` file)
- \[ ] `cargo test` passes locally
- \[ ] Executed `cargo dev update_lints`
- \[ ] Added lint documentation
- \[ ] Run `cargo dev fmt`
[lint_naming]: https://rust-lang.github.io/rfcs/0344-conventions-galore.html#lints
Note that you can skip the above if you are just opening a WIP PR in
order to get feedback.
Delete this line and everything above before opening your PR.
--
*Please write a short comment explaining your change (or "none" for internal only changes)*
-->
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.
Don't lint Default::default if it is the udpate syntax base
changelog: Don't lint `Default::default` it is part of the update syntax
Current clippy warns about this:
```
warning: calling `Foo::default()` is more clear than this expression
--> src/main.rs:12:11
|
12 | ..Default::default()
| ^^^^^^^^^^^^^^^^^^ help: try: `Foo::default()`
|
```
With these changes, it will not lint that particular expression anymore.
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.)
Fix `transmute_undefined_repr` with single field `#[repr(C)]` structs
Fixes: #8417
The description has also been made more precise.
changelog: Fix `transmute_undefined_repr` with single field `#[repr(C)]` structs
changelog: Move `transmute_undefined_repr` back to `correctness`
Support `cargo dev bless` for tests with revisions
changelog: internal: Support `cargo dev bless` for tests with revisions
Previously bless wouldn't pick up the saved stderr from `target/debug/tests/manual_assert.stage-id.edition2021.stderr` or `target/debug/tests/manual_assert.stage-id.edition2018.stderr` due to there being multiple revisions of the test output
This tweaks compile-test so the built files end up in e.g. `target/debug/tests/ui`, `target/debug/tests/ui-cargo` rather than share the `tests` dir. `cargo dev bless` then uses that to update all the `.stdout/stdout/fixed` files it can find
Also removes an empty file I found, and the logic to remove empty outputs as compiletest doesn't produce empty `.stdout/stderr` files
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`
Add `explicit_write` suggestions for `write!`s with format args
changelog: Add [`explicit_write`] suggestions for `write!`s with format args
Fixes#4542
```rust
writeln!(std::io::stderr(), "macro arg {}", one!()).unwrap();
```
Now suggests:
```
error: use of `writeln!(stderr(), ...).unwrap()`
--> $DIR/explicit_write.rs:36:9
|
LL | writeln!(std::io::stderr(), "macro arg {}", one!()).unwrap();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `eprintln!("macro arg {}", one!())`
```
---------
r? `@camsteffen` (again, sorry 😛) for the `FormatArgsExpn` change
Before this change `inputs_span` returned a span pointing to just `1` in
```rust
macro_rules! one {
() => { 1 };
}
`writeln!(std::io::stderr(), "macro arg {}", one!()).unwrap();`
```
And the `source_callsite` of that span didn't include the format string, it was just `one!()`
make unwrap_used also trigger on .get().unwrap()
fixes#8124
changelog: make the [unwrap_used] lint trigger for code of the form such as `.get(i).unwrap()` and `.get_mut(i).unwrap()`
[explicit_counter_loop] suggests `.into_iter()`, despite that triggering [into_iter_on_ref] in some cases
I have modified `fn make_iterator_snippet` in clippy_lints/src/loops/utils.rs ,so this change has some little influence on another lint [manual_flatten] .
fixes#8155
---
changelog: Fix that [`explicit_counter_loop`] suggests `into_iter()` despite that triggering [`into_iter_on_ref`] in some cases
single_match: Don't lint non-exhaustive matches; support tuples
`single_match` lint:
* Don't lint exhaustive enum patterns without a wild.
Rationale: The definition of the enum could be changed, so the user can get non-exhaustive match after applying the suggested lint (see https://github.com/rust-lang/rust-clippy/issues/8282#issuecomment-1013566068 for context).
* Lint `match` constructions with tuples (as suggested at https://github.com/rust-lang/rust-clippy/issues/8282#issuecomment-1015621148)
Closes#8282
---
changelog: [`single_match`]: Don't lint exhaustive enum patterns without a wild.
changelog: [`single_match`]: Lint `match` constructions with tuples
Fix underflow in `manual_split_once` lint
Hi, a friend found clippy started crashing on a suspiciously large allocation of `u64::MAX` memory on their code.
The mostly minimized repro is:
```rust
fn _f01(title: &str) -> Option<()> {
let _ = title[1..].splitn(2, '[').next()?;
Some(())
}
```
The underflow happens in this case on line 57 of the patch but I've changed the other substraction to saturating as well since it could potentially cause the same issue.
I'm not sure where to put a regression test, or if it's even worth for such a thing.
Aside, has it been considered before to build clippy with overflow checks enabled?
changelog: fix ICE of underflow in `manual_split_once` lint
Fix `needless_borrow` causing mutable borrows to be moved
fixes#8191
changelog: Fix `needless_borrow` causing mutable borrows to be moved
changelog: Rename `ref_in_deref` to `needless_borrow`
changelog: Suggest removing the borrow on method call receivers in `needless_borrow`
Check usages in `ptr_arg`
fixes#214fixes#1981fixes#3381fixes#6406fixes#6964
This does not take into account the return type of the function currently, so `(&Vec<_>) -> &Vec<_>` functions may still be false positives.
The name given for the type also has to match the real type name, so `type Foo = Vec<u32>` won't trigger the lint, but `type Vec = Vec<u32>` will. I'm not sure if this is the best way to handle this, or if a note about the actual type should be added instead.
changelog: Check if the argument is used in a way which requires the original type in `ptr_arg`
changelog: Lint mutable references in `ptr_arg`
This commit changes the behavior of `single_match` lint.
After that, we won't lint non-exhaustive matches like this:
```rust
match Some(v) {
Some(a) => println!("${:?}", a),
None => {},
}
```
The rationale is that, because the type of `a` could be changed, so the
user can get non-exhaustive match after applying the suggested lint (see
https://github.com/rust-lang/rust-clippy/issues/8282#issuecomment-1013566068
for context).
We also will lint `match` constructions with tuples. When we see the
tuples on the both arms, we will check them both at the same time, and
if they form exhaustive match, we could display the warning.
Closes#8282
fix op_ref false positive
fixes#7572
changelog: `op_ref` don't lint for unnecessary reference in BinOp impl if removing the reference will lead to unconditional recursion
issue #8239: Printed hint for lint or_fun_call is cropped and does no…
fixesrust-lang/rust-clippy#8239
changelog: [`or_fun_call`]: if suggestion contains more lines than MAX_SUGGESTION_HIGHLIGHT_LINES it is stripped to one line
* Track the argument when used to initialize simple `let` bindings
* Check if the argument is passed to a function requiring the original type
* Use `multipart_suggestion` rather than multiple suggestions
* Check if the name given in the source code matches the name of the actual type
`manual_memcpy` fix
fixes#8160
Ideally this would work with `VecDeque`, but the current interface is unsuitable for it. At a minimum something like `range_as_slices` would be needed.
changelog: Don't lint `manual_memcpy` on `VecDeque`
changelog: Suggest `copy_from_slice` for `manual_memcpy` when applicable
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`]
Better detect when a field can be moved from in `while_let_on_iterator`
fixes#8113
changelog: Better detect when a field can be moved from in `while_let_on_iterator`
Fix `type_repetition_in_bounds`
fixes#7360fixes#8162fixes#8056
changelog: Check for full equality in `type_repetition_in_bounds` rather than just equal hashes
New macro utils
changelog: none
Sorry, this is a big one. A lot of interrelated changes and I wanted to put the new utils to use to make sure they are somewhat battle-tested. We may want to divide some of the lint-specific refactoring commits into batches for smaller reviewing tasks. I could also split into more PRs.
Introduces a bunch of new utils at `clippy_utils::macros::...`. Please read through the docs and give any feedback! I'm happy to introduce `MacroCall` and various functions to retrieve an instance. It feels like the missing puzzle piece. I'm also introducing `ExpnId` from rustc as "useful for Clippy too". `@rust-lang/clippy`
Fixes#7843 by not parsing every node of macro implementations, at least the major offenders.
I probably want to get rid of `is_expn_of` at some point.
changelog: none
Sorry, this is a big one. A lot of interrelated changes and I wanted to put the new utils to use to make sure they are somewhat battle-tested. We may want to divide some of the lint-specific refactoring commits into batches for smaller reviewing tasks. I could also split into more PRs.
Introduces a bunch of new utils at `clippy_utils::macros::...`. Please read through the docs and give any feedback! I'm happy to introduce `MacroCall` and various functions to retrieve an instance. It feels like the missing puzzle piece. I'm also introducing `ExpnId` from rustc as "useful for Clippy too". `@rust-lang/clippy`
Fixes#7843 by not parsing every node of macro implementations, at least the major offenders.
I probably want to get rid of `is_expn_of` at some point.
wrong_self_convention: Match `SelfKind::No` more restrictively
The `wrong_self_convention` lint uses a `SelfKind` type to decide
whether a method has the right kind of "self" for its name, or whether
the kind of "self" it has makes its name confusable for a method in
a common trait. One possibility is `SelfKind::No`, which is supposed
to mean "No `self`".
Previously, SelfKind::No matched everything _except_ Self, including
references to Self. This patch changes it to match Self, &Self, &mut
Self, Box<Self>, and so on.
For example, this kind of method was allowed before:
```
impl S {
// Should trigger the lint, because
// "methods called `is_*` usually take `self` by reference or no `self`"
fn is_foo(&mut self) -> bool { todo!() }
}
```
But since SelfKind::No matched "&mut self", no lint was triggered
(see #8142).
With this patch, the code above now gives a lint as expected.
fixes#8142
changelog: [`wrong_self_convention`] rejects `self` references in more cases
Inspired by a discussion in rust-lang/rust-clippy#8197
---
r? `@llogiq`
changelog: none
The lint is this on nightly, therefore no changelog entry for you xD
The `wrong_self_convention` lint uses a `SelfKind` type to decide
whether a method has the right kind of "self" for its name, or whether
the kind of "self" it has makes its name confusable for a method in
a common trait. One possibility is `SelfKind::No`, which is supposed
to mean "No `self`".
Previously, SelfKind::No matched everything _except_ Self, including
references to Self. This patch changes it to match Self, &Self, &mut
Self, Box<Self>, and so on.
For example, this kind of method was allowed before:
```
impl S {
// Should trigger the lint, because
// "methods called `is_*` usually take `self` by reference or no `self`"
fn is_foo(&mut self) -> bool { todo!() }
}
```
But since SelfKind::No matched "&mut self", no lint was triggered
(see #8142).
With this patch, the code above now gives a lint as expected.
Fixes#8142
changelog: [`wrong_self_convention`] rejects `self` references in more cases
This improves the quality of the genrated output and makes it
more in line with other lint messages.
changelog: [`unused_io_amount`]: Improve help text
Clippy helpfully warns about code like this, telling you that you
probably meant "write_all":
fn say_hi<W:Write>(w: &mut W) {
w.write(b"hello").unwrap();
}
This patch attempts to extend the lint so it also covers this
case:
async fn say_hi<W:AsyncWrite>(w: &mut W) {
w.write(b"hello").await.unwrap();
}
(I've run into this second case several times in my own programming,
and so have my coworkers, so unless we're especially accident-prone
in this area, it's probably worth addressing?)
This patch covers the Async{Read,Write}Ext traits in futures-rs,
and in tokio, since both are quite widely used.
changelog: [`unused_io_amount`] now supports AsyncReadExt and AsyncWriteExt.
Limit the ``[`identity_op`]`` lint to integral operands.
changelog: limit ``[`identity_op`]`` to integral operands
In the ``[`identity_op`]`` lint, if the operands are non-integers, then the lint is likely
wrong.
Fixed issues with to_radians and to_degrees lints
fixes#7651
I fixed the original problem as described in the issue, but the bug remains for complex expressions (the commented out TC I added is an example). I would also love some feedback on how to cleanup my code and reduce duplication. I hope it's not a problem that the issue has been claimed by someone else - that was over two months ago.
changelog: ``[`suboptimal_flops`]`` no longer proposes broken code with `to_radians` and `to_degrees`
Fix `enum_variants` FP on prefixes that are not camel-case
closes#8090
Fix FP on `enum_variants` when prefixes are only a substring of a camel-case word. Also adds some util helpers on `str_utils` to help parsing camel-case strings.
This changes how the lint behaves:
1. previously if the Prefix is only a length of 1, it's going to get ignored, i.e. these were previously ignored and now is warned
```rust
enum Foo {
cFoo,
cBar,
cBaz,
}
enum Something {
CCall,
CCreate,
CCryogenize,
}
```
2. non-ascii characters that doesn't have casing will not be split,
```rust
enum NonCaps {
PrefixXXX,
PrefixTea,
PrefixCake,
}
```
will be considered as `PrefixXXX`, `Prefix`, `Prefix`, so this won't lint as opposed to fired previously.
changelog: [`enum_variant_names`] Fix FP when first prefix are only a substring of a camel-case word.
---
(Edited by `@xFrednet` removed some non ascii characters)
closes#8177
previously, `needless_return` suggests an empty block `{}` to replace void `return` on match arms, this PR improve the suggestion by suggesting a unit instead.
changelog: `needless_return` suggests `()` instead of `{}` on match arms
Fix `SAFETY` comment tag casing in undocumented_unsafe_blocks
This changes the lint introduced in #7748 to suggest adding a `SAFETY` comment instead of a `Safety` comment.
Searching for `// Safety:` in rust-lang/rust yields 67 results while `// SAFETY:` yields 1072.
I think it's safe to say that this comment tag is written in upper case, just like `TODO`, `FIXME` and so on are. As such I would expect this lint to follow the official convention as well.
Note that I intentionally introduced some casing diversity in `tests/ui/undocumented_unsafe_blocks.rs` to test more cases than just `Safety:`.
changelog: Capitalize `SAFETY` comment in [`undocumented_unsafe_blocks`]
Don't emit RETURN_SELF_NOT_MUST_USE lint if `Self` already is marked as `#[must_use]`
New bug discovered with this lint. Hopefully, this is the last one.
---
changelog: none
Ensure that RETURN_SELF_NOT_MUST_USE is not emitted if the method already has `#[must_use]`
Fixes https://github.com/rust-lang/rust-clippy/issues/8140.
---
Edit:
changelog: none
(The lint is not in beta yet, this should therefore not be included inside the changelog :) )
Implement let-else type annotations natively
Tracking issue: #87335Fixes#89688, fixes#89807, edit: fixes #89960 as well
As explained in https://github.com/rust-lang/rust/issues/89688#issuecomment-940405082, the previous desugaring moved the let-else scrutinee into a dummy variable, which meant if you wanted to refer to it again in the else block, it had moved.
This introduces a new hir type, ~~`hir::LetExpr`~~ `hir::Let`, which takes over all the fields of `hir::ExprKind::Let(...)` and adds an optional type annotation. The `hir::Let` is then treated like a `hir::Local` when type checking a function body, specifically:
* `GatherLocalsVisitor` overrides a new `Visitor::visit_let_expr` and does pretty much exactly what it does for `visit_local`, assigning a local type to the `hir::Let` ~~(they could be deduplicated but they are right next to each other, so at least we know they're the same)~~
* It reuses the code in `check_decl_local` to typecheck the `hir::Let`, simply returning 'bool' for the expression type after doing that.
* ~~`FnCtxt::check_expr_let` passes this local type in to `demand_scrutinee_type`, and then imitates check_decl_local's pattern checking~~
* ~~`demand_scrutinee_type` (the blindest change for me, please give this extra scrutiny) uses this local type instead of of creating a new one~~
* ~~Just realised the `check_expr_with_needs` was passing NoExpectation further down, need to pass the type there too. And apparently this Expectation API already exists.~~
Some other misc notes:
* ~~Is the clippy code supposed to be autoformatted? I tried not to give huge diffs but maybe some rustfmt changes simply haven't hit it yet.~~
* in `rustc_ast_lowering/src/block.rs`, I noticed some existing `self.alias_attrs()` calls in `LoweringContext::lower_stmts` seem to be copying attributes from the lowered locals/etc to the statements. Is that right? I'm new at this, I don't know.
Tweak errors coming from `for`-loop, `?` and `.await` desugaring
* Suggest removal of `.await` on non-`Future` expression
* Keep track of obligations introduced by desugaring
* Remove span pointing at method for obligation errors coming from desugaring
* Point at called local sync `fn` and suggest making it `async`
```
error[E0277]: `()` is not a future
--> $DIR/unnecessary-await.rs:9:10
|
LL | boo().await;
| -----^^^^^^ `()` is not a future
| |
| this call returns `()`
|
= help: the trait `Future` is not implemented for `()`
help: do not `.await` the expression
|
LL - boo().await;
LL + boo();
|
help: alternatively, consider making `fn boo` asynchronous
|
LL | async fn boo () {}
| +++++
```
Fix#66731.
Stabilize asm! and global_asm!
Tracking issue: #72016
It's been almost 2 years since the original [RFC](https://github.com/rust-lang/rfcs/pull/2850) was posted and we're finally ready to stabilize this feature!
The main changes in this PR are:
- Removing `asm!` and `global_asm!` from the prelude as per the decision in #87228.
- Stabilizing the `asm` and `global_asm` features.
- Removing the unstable book pages for `asm` and `global_asm`. The contents are moved to the [reference](https://github.com/rust-lang/reference/pull/1105) and [rust by example](https://github.com/rust-lang/rust-by-example/pull/1483).
- All links to these pages have been removed to satisfy the link checker. In a later PR these will be replaced with links to the reference or rust by example.
- Removing the automatic suggestion for using `llvm_asm!` instead of `asm!` if you're still using the old syntax, since it doesn't work anymore with `asm!` no longer being in the prelude. This only affects code that predates the old LLVM-style `asm!` being renamed to `llvm_asm!`.
- Updating `stdarch` and `compiler-builtins`.
- Updating all the tests.
r? `@joshtriplett`
fix clippy format using `cargo fmt -p clippy_{lints,utils}`
manually revert rustfmt line truncations
rename to hir::Let in clippy
Undo the shadowing of various `expr` variables after renaming `scrutinee`
reduce destructuring of hir::Let to avoid `expr` collisions
cargo fmt -p clippy_{lints,utils}
bless new clippy::author output
Add new lint to warn when #[must_use] attribute should be used on a method
This lint is somewhat similar to https://rust-lang.github.io/rust-clippy/master/index.html#must_use_candidate but also different: it emits a warning by default and only targets methods (so not functions nor associated functions).
Someone suggested it to me after this tweet: https://twitter.com/m_ou_se/status/1466439813230477312
I think it would reduce the number of cases of API misuses quite a lot.
What do you think?
---
changelog: Added new [`return_self_not_must_use`] lint
Ignore associated types in traits when considering type complexity
changelog: Ignore associated types in traits when checking ``[`type_complexity`]`` lint.
fixes#1013
Fix bad suggestion on `option_if_let_else` when there is complex subpat
closes#7991
Prefer not warning any complex subpat in `option_if_let_else` rather than suggesting obscure suggestions.
changelog: [`option_if_let_else`] does not warn when complex subpat is present
Parenthesize blocks in `needless_bool` suggestion
Because the `if .. {}` statement already puts the condition in expression scope, contained blocks would be parsed as complete
statements, so any `&` binary expression whose left operand ended in a block would lead to a non-compiling suggestion.
We identify such expressions and add parentheses. Note that we don't make a difference between normal and unsafe blocks because the parsing problems are the same for both.
This fixes#8052.
---
changelog: none
Because the `if .. {}` statement already puts the condition in
expression scope, contained blocks would be parsed as complete
statements, so any `&` binary expression whose left operand ended in a
block would lead to a non-compiling suggestion.
This adds a visitor to identify such expressions and add parentheses.
This fixes#8052.
Consider NonNull as a pointer type
PR 1/2 for issue #8045. Add `NonNull` as a pointer class to suppress false positives like `UnsafeCell<NonNull<()>>`. However, this change is not sufficient to handle the cases shared in gtk-rs and Rug in the issue.
changelog: none
r? `@xFrednet`
Fix `any()` not taking reference in `search_is_some` lint
`find` gives reference to the item, but `any` does not, so suggestion is broken in some specific cases.
Fixes: #7392
changelog: [`search_is_some`] Fix suggestion for `any()` not taking item by reference
Add test for pattern_type_mismatch.
This issue has been fixed by [commit](8c1c763c2d)
This PR is used for close #7946(Fixes#7946).
changelog: Add test for pattern_type_mismatch.
Improve `strlen_on_c_string`
fixes: #7436
changelog: lint `strlen_on_c_string` when used without a fully-qualified path
changelog: suggest removing the surrounding unsafe block for `strlen_on_c_string` when possible
Prior to PR #91205, checking for errors in the overall obligation
would check checking the `ParamEnv`, due to an incorrect
`super_visit_with` impl. With this bug fixed, we will now
bail out of impl candidate assembly if the `ParamEnv` contains
any error types.
In practice, this appears to be overly conservative - when an error
occurs early in compilation, we end up giving up early for some
predicates that we could have successfully evaluated without overflow.
By only checking for errors in the predicate itself, we avoid causing
additional spurious 'type annotations needed' errors after a 'real'
error has already occurred.
With this PR, the diagnostic changes caused by PR #91205 are reverted.
Add `needless_late_init` lint
examples:
```rust
let a;
a = 1;
// to
let a = 1;
```
```rust
let b;
match 3 {
0 => b = "zero",
1 => b = "one",
_ => b = "many",
}
// to
let b = match 3 {
0 => "zero",
1 => "one",
_ => "many",
};
```
```rust
let c;
if true {
c = 1;
} else {
c = -1;
}
// to
let c = if true {
1
} else {
-1
};
```
changelog: Add [`needless_late_init`]
Visit `param_env` field in Obligation's `TypeFoldable` impl
This oversight appears to have gone unnoticed for a long time
without causing issues, but it should still be fixed.
Add new lint `octal_escapes`
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.
Fixes#7981
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: Add new lint [`octal_escapes`], which checks for literals like `"\033[0m"`.
Allow `suboptimal_flops` in const functions
This PR allows `clippy::suboptimal_flops` in constant functions. The check also effects the `clippy::imprecise_flops` lint logic. However, this doesn't have any effects as all functions checked for are not const and can therefore not be found in such functions.
---
changelog: [`suboptimal_flops`]: No longer triggers in constant functions
Closes: rust-lang/rust-clippy#8004
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.
Pluralize `disallowed_type` lint
This was brought up in [Zulip] and is also mentioned in the lint naming
conventions. Since this is still a nursery lint, I think there shouldn't
be any problem in renaming it.
[Zulip]: rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/disallow_type.20vs.20disallowed-types
changelog: Rename nursery lint [`disallowed_type`] to [`disallowed_types`].
Improve `needless_borrow` lint
fixes: #5327fixes: #1726fixes: #1212
This is merging `needless_borrow` into the `dereference` pass in preparation for `explicit_auto_deref`. `explicit_auto_deref` needs to implement most of what `needless_borrow` implements in order to work.
There is a minor regression here where `let x: &str = &x.deref()` will trigger `needless_borrow` without triggering `explicit_deref_methods`. Removing the redundant borrow will cause `explicit_deref_methods` to trigger. This will be fixed when `explicit_auto_deref` is implemented.
changelog: Lint `needless_borrow` when a borrow is auto-derefed more than once
changelog: Lint `needless_borrow` in the trailing expression of a block for a match arm
Don't show no_effect warning on unit structs implementing fn_once
Fixes#7792
changelog: Don't show [`no_effect`] or [`unecessary_operation`] warning for unit struct implementing FnOnce
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.
Fix `needless_collect`'s tendency to suggest code requiring multiple mutable borrows of the same value.
Fixes error specified in #7975.
changelog: [`needless_collect`] no longer suggests removal of `collect` when removal would create code requiring mutably borrowing a value multiple times.
* Lint when a borrow is auto dereferenced more than once
* Lint when the expression is used as the expression of a block for a match arm
Moves `needless_borrow` and `ref_binding_to_reference` to `dereference`
lint pass in preperation for `explicit_auto_deref` lint.
Support suggestion for #7854
I think the detection of parking_lot's mutex and rwlock is valuable, so submit this pr, please help judge and review, thank you.
Make let_underscore_lock support parking_lot.(Fixes#7854)
changelog: Make let_underscore_lock support parking_lot
I think the detection of parking_lot's mutex and rwlock is valuable, so submit this pr, please help judge and review, thank you.
Make let_underscore_lock support parking_lot.
changelog: Make let_underscore_lock support parking_lot
Lint for bool to integer casts in `cast_lossless`
The lint description says
> Checks for casts between *numerical* types that may be replaced by safe conversion functions.
Which is strictly speaking being violated here, but it seems within the spirit of the lint. I think it is still a useful lint to have, and having a different lint for just this feels excessive. Thoughts?
Fixes#7947
changelog: Lint for bool to integer casts in [`cast_lossless`]
Author improvements
changelog: none
Various aspects of the author implementation are re-imagined to be much less repetitive. Also fixes some bugs. I hope this makes author more fun to work on for future contributors.
The last commit is pretty heavy but I tried to at least separate some changes so that the test file diffs per commit are simple.
* 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
Fix `explicit_counter_loop` suggestion for non-usize types
changelog: Add a new suggestion for non-usize types in [`explicit_counter_loop`]
closes: #7920
Fix suggestion for deref expressions in redundant_pattern_matching
changelog: Fix suggestion for deref expressions in [`redundant_pattern_matching`]
closes: #7921
The only reason to use `abort_if_errors` is when the program is so broken that either:
1. later passes get confused and ICE
2. any diagnostics from later passes would be noise
This is never the case for lints, because the compiler has to be able to deal with `allow`-ed lints.
So it can continue to lint and compile even if there are lint errors.
