If the type of the result of a call to `IntoIterator::into_iter()`
and the type of the receiver are the same, then the receiver
implements `Iterator` and `into_iter()` is the identity function.
The call to `into_iter()` may be removed in all but two cases:
- If the receiver implements `Copy`, `into_iter()` will produce
a copy of the receiver and cannot be removed. For example,
`x.into_iter().next()` will not advance `x` while `x.next()` will.
- If the receiver is an immutable local variable and the call to
`into_iter()` appears in a larger expression, removing the call to
`into_iter()` might cause mutability issues. For example, if `x`
is an immutable local variable, `x.into_iter().next()` will
compile while `x.next()` will not as `next()` receives
`&mut self`.
Rustup
r? `@ghost`
I'm on the train and my internet is too bad to download the necessary toolchain, so I have to use CI to find sync fallout.
changelog: none
<!-- changelog_checked -->
fix: not suggest seek_to_start_instead_of_rewind when expr is used
changelog: [`seek_to_start_instead_of_rewind`]: No longer lints, if the return of `seek` is used.
[#10096](https://github.com/rust-lang/rust-clippy/pull/10096)
<!-- changelog_checked -->
Fixes#10065
There used to be a logical bug where IncrementVisitor would
completely stop checking an expression/block after seeing a continue
statement. This led to issue #10058 where a variable incremented
(or otherwise modified) after any continue statement would still be
considered incremented only once.
The solution is to continue scanning the expression after seeing a
`continue` statement, but increment self.depth so that the Visitor
thinks that the rest of the loop is within a conditional.
Changelog 1.66
It's really nice to see a changelog with so many suggestion fixes and improvements. Not much else to say. This should be merged with the coming release on 2022-12-15. For the reviewer, please review it and approve it if it looks good. The merge should wait until the release :)
---
changelog: none
<!-- changelog_checked -->
improve `manual_is_ascii_check ` check
Sorry, not familiar the api, i can only check the method name of expression `<expr-1>.contains(<expr-2>)` after read clippy book and hints from #9933 . i dont know how to check
1. if <expr-1> is a specific range
2. <expr-2> is a character
r? `@xFrednet` could you please provide some more hints? 😝️
---
changelog: Enhancement: [`manual_is_ascii_check`]: Now detects ranges with `.contains()` calls
[#10053](https://github.com/rust-lang/rust-clippy/pull/10053)
<!-- changelog_checked -->
Remove `token::Lit` from `ast::MetaItemLit`.
Currently `ast::MetaItemLit` represents the literal kind twice. This PR removes that redundancy. Best reviewed one commit at a time.
r? `@petrochenkov`
Add 1.58 MSRV for `collapsible_str_replace`
The `Pattern` impl for `[char; N]` was added in 1.58
changelog: Enhancement: [`collapsible_str_replace`]: Now takes MSRV into consideration. The minimal version is 1.58
[#10047](https://github.com/rust-lang/rust-clippy/pull/10047)
add `suppress_restriction_lint_in_const` config
According to #9808 , add a new lint `suppress_lint_in_const` to report even in const context. BTW, i am not good at naming either, if anyone have a better idea, i am happy to change it.
This PR is still in progress, so i keep it draft.
- \[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`
changelog: Enhancement: [`indexing_slicing`]: add new config `suppress-restriction-lint-in-const` to enable restriction lints, even if the suggestion might not be applicable
r? `@xFrendet`
Fix 10021
This PR proposes a fix for #10021.
The problem is similar to the one that `@mikerite` described in #9505. The compiler is generating an empty substitution for a call, even though the type of `Self` seems to be needed for a predicate. In `@mikerite's` case, the call was to [`IntoFuture::into_future`](https://doc.rust-lang.org/std/future/trait.IntoFuture.html#tymethod.into_future). In this case, the call is to [`Try::branch`](https://doc.rust-lang.org/std/ops/trait.Try.html#tymethod.branch).
The proposed fix is to verify that the parameter whose type is changing has an index within the substitution. The strikes me as a reasonable approach, since if the check were to fail, the following code would be a no-op:
4c123a06ba/clippy_lints/src/methods/unnecessary_to_owned.rs (L420-L428)
Like `@mikerite's` original solution, this solution turns ICEs into false negatives.
changelog: fix `unnecessary_to_owned` false positive involving `Try::branch`
Don't lint `implicit_clone` when the type doesn't implement clone
fixes#10019
changelog: `implicit_clone`: Don't lint when the type doesn't implement clone
Fix#9958
This PR fixes#9958. In order to fix the issue, the lint will now peel reference operators and enclose the expression with parentheses when necessary.
changelog: [`comparison_to_empty`]: Peel deref operators in suggestions when necessary
Don't lint `from_over_into` for opaque types
fixes#9935
This is stalled until the next sync. The impl in question can't be written on the pinned nightly.
changelog: Don't lint `from_over_into` for opaque types
rustc_ast_lowering: Stop lowering imports into multiple items
Lower them into a single item with multiple resolutions instead.
This also allows to remove additional `NodId`s and `DefId`s related to those additional items.
This is required to distinguish between cooked and raw byte string
literals in an `ast::LitKind`, without referring to an adjacent
`token::Lit`. It's a prerequisite for the next commit.
Lower them into a single item with multiple resolutions instead.
This also allows to remove additional `NodId`s and `DefId`s related to those additional items.
Don't lint `explicit_auto_deref` when the initial type is neither a reference, nor a receiver
fixes#9901fixes#9777
changelog: `explicit_auto_deref`: Don't lint when the initial value is neither a reference, nor a receiver
Don't cross contexts while building the suggestion for `redundant_closure_call`
fixes#9957
changelog: `redundant_closure_call`: Don't cross macro contexts while building the suggestion
Move `unnecessary_unsafety_doc` to `pedantic`
This lint was added in #9822. I like the idea, but also agree with #9986 as well. I think it should at least not be warn-by-default. This is one of these cases, where I'd like a group between pedantic and restriction. But I believe that users using `#![warn(clippy::pedantic)]` will know how to enable the lint if they disagree with it.
---
Since the lint is new:
changelog: none
r? `@flip1995` since I'd suggest back porting this, the original PR was merged 16 days ago.
Closes: #9986 (While it doesn't address everything, I believe that this is the best compromise)
Move `index_refutable_slice` to `pedantic`
During the creation, I out this lint into the nursery group to let it run in the wild before moving it to a commonly used group. This move never happened until now, though. It should be safe, as Clippy and I have been using it for months and there are no open issues for is :)
---
changelog: Move `index_refutable_slice` to `pedantic` (Now warn-by-default)
[#9975](https://github.com/rust-lang/rust-clippy/pull/9975)
Add allow-mixed-uninlined-format-args config
Implement `allow-mixed-uninlined-format-args` config param to change the behavior of the `uninlined_format_args` lint. Now it is a part of `style` per [Zulip chat](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/.60uninlined_format_args.60.20category), and won't propose inlining in case of a mixed usage, e.g. `print!("{} {}", var, 1+2)`. If the user sets `allow-mixed-uninlined-format-args` config param to `false`, the lint would behave like it did before -- proposing to inline args even in the mixed case.
---
changelog: [`uninlined_format_args`]: Added a new config `allow-mixed-uninlined-format-args` to allow the lint, if only some arguments can be inlined
[#9865](https://github.com/rust-lang/rust-clippy/pull/9865)
changelog: Moved [`uninlined_format_args`] to `style` (Now warn-by-default)
[#9865](https://github.com/rust-lang/rust-clippy/pull/9865)
Implement `allow-mixed-uninlined-format-args` config param to change the behavior of the `uninlined_format_args` lint. Now it is a part of `style`, and won't propose inlining in case of a mixed usage, e.g. `print!("{} {}", var, 1+2)`. If the user sets allow-mixed-uninlined-format-args config param to `false`, then it would behave like before, proposing to inline args even in the mixed case.
Separate lifetime ident from lifetime resolution in HIR
Drive-by: change how suggested generic args are computed.
Fixes https://github.com/rust-lang/rust/issues/103815
I recommend reviewing commit-by-commit.
Make rustc_target usable outside of rustc
I'm working on showing type size in rust-analyzer (https://github.com/rust-lang/rust-analyzer/pull/13490) and I currently copied rustc code inside rust-analyzer, which works, but is bad. With this change, I would become able to use `rustc_target` and `rustc_index` directly in r-a, reducing the amount of copy needed.
This PR contains some feature flag to put nightly features behind them to make crates buildable on the stable compiler + makes layout related types generic over index type + removes interning of nested layouts.
Avoid `GenFuture` shim when compiling async constructs
Previously, async constructs would be lowered to "normal" generators, with an additional `from_generator` / `GenFuture` shim in between to convert from `Generator` to `Future`.
The compiler will now special-case these generators internally so that async constructs will *directly* implement `Future` without the need to go through the `from_generator` / `GenFuture` shim.
The primary motivation for this change was hiding this implementation detail in stack traces and debuginfo, but it can in theory also help the optimizer as there is less abstractions to see through.
---
Given this demo code:
```rust
pub async fn a(arg: u32) -> Backtrace {
let bt = b().await;
let _arg = arg;
bt
}
pub async fn b() -> Backtrace {
Backtrace::force_capture()
}
```
I would get the following with the latest stable compiler (on Windows):
```
4: async_codegen:🅱️:async_fn$0
at .\src\lib.rs:10
5: core::future::from_generator::impl$1::poll<enum2$<async_codegen:🅱️:async_fn_env$0> >
at /rustc/897e37553bba8b42751c67658967889d11ecd120\library\core\src\future\mod.rs:91
6: async_codegen:🅰️:async_fn$0
at .\src\lib.rs:4
7: core::future::from_generator::impl$1::poll<enum2$<async_codegen:🅰️:async_fn_env$0> >
at /rustc/897e37553bba8b42751c67658967889d11ecd120\library\core\src\future\mod.rs:91
```
whereas now I get a much cleaner stack trace:
```
3: async_codegen:🅱️:async_fn$0
at .\src\lib.rs:10
4: async_codegen:🅰️:async_fn$0
at .\src\lib.rs:4
```
Previously, async constructs would be lowered to "normal" generators,
with an additional `from_generator` / `GenFuture` shim in between to
convert from `Generator` to `Future`.
The compiler will now special-case these generators internally so that
async constructs will *directly* implement `Future` without the need
to go through the `from_generator` / `GenFuture` shim.
The primary motivation for this change was hiding this implementation
detail in stack traces and debuginfo, but it can in theory also help
the optimizer as there is less abstractions to see through.
Add `clippy_utils::msrv::Msrv` to keep track of the current MSRV
changelog: Fix the scoping of the `#![clippy::msrv]` attribute
Fixes#6920
r? `@Jarcho`
Update Clippy
r? `@Manishearth`
Sorry for taking so long. There were so many blockers and so little time. This situation should be mitigated with #104007 in the future.
Fix#9771 (`unnecessary_to_owned` false positive)
Fixes#9771
In that issue's example(s), the lint tried to add a `&` to a value, which implicitly changed the type of a field to a reference. The fix is to add the reference to `receiver_ty` (the type of the receiver of the `to_owned`-like method), before passing `receiver_ty` to `can_change_type`. `can_change_type` properly rejects the modified `receiver_ty`.
cc: `@mikerite` just because I think he was the author of `can_change_type`.
changelog: fix `unnecessary_to_owned` false positive which implicitly tried to change the type of a field to a reference
Fix `redundant_closure_for_method_calls` suggestion
Fixes#7746. The issue turns out to be more general than raw pointers. The `redundant_closure_for_method_calls` lint produces incorrect suggestions when the method is associated with a type that must be enclosed in angle brackets or must be written with generic arguments substituted. For example:
```rust
fn main() {
// Clippy's suggestion: [T; N]::as_slice
// Correct suggestion: <[u8; 3]>::as_slice
let array_opt: Option<&[u8; 3]> = Some(&[4, 8, 7]);
array_opt.map(|a| a.as_slice());
// Clippy's suggestion: [T]::len
// Correct suggestion: <[u8]>::len
let slice_opt: Option<&[u8]> = Some(b"slice");
slice_opt.map(|s| s.len());
// Clippy's suggestion: *const T::is_null
// Correct suggestion: <*const usize>::is_null
let ptr_opt: Option<*const usize> = Some(&487);
ptr_opt.map(|p| p.is_null());
// Clippy's suggestion: dyn TestTrait::method_on_dyn
// Correct suggestion: <dyn TestTrait>::method_on_dyn
let test_struct = TestStruct {};
let dyn_opt: Option<&dyn TestTrait> = Some(&test_struct);
dyn_opt.map(|d| d.method_on_dyn());
}
// For the trait object example:
trait TestTrait {}
struct TestStruct {}
impl TestTrait for TestStruct {}
impl dyn TestTrait + '_ {
fn method_on_dyn(&self) -> bool {
false
}
}
```
The issue also affects references and tuples, though I had to patch the standard library with non-trait methods for those types to test that. Just in case, I also included handling for `!`, since it appeared to be possible to call methods on it with angle brackets. I just couldn't verify the resulting suggestion, since dead-code analysis eliminates the code first.
This is my first exposure to Rust compiler internals, so please let me know if I'm taking the wrong approach here!
changelog: [`redundant_closure_for_method_calls`]: add angle brackets and substitute generic arguments in suggestion when needed
Rollup of 11 pull requests
Successful merges:
- #103396 (Pin::new_unchecked: discuss pinning closure captures)
- #104416 (Fix using `include_bytes` in pattern position)
- #104557 (Add a test case for async dyn* traits)
- #104559 (Split `MacArgs` in two.)
- #104597 (Probe + better error messsage for `need_migrate_deref_output_trait_object`)
- #104656 (Move tests)
- #104657 (Do not check transmute if has non region infer)
- #104663 (rustdoc: factor out common button CSS)
- #104666 (Migrate alias search result to CSS variables)
- #104674 (Make negative_impl and negative_impl_exists take the right types)
- #104692 (Update test's cfg-if dependency to 1.0)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
`MacArgs` is an enum with three variants: `Empty`, `Delimited`, and `Eq`. It's
used in two ways:
- For representing attribute macro arguments (e.g. in `AttrItem`), where all
three variants are used.
- For representing function-like macros (e.g. in `MacCall` and `MacroDef`),
where only the `Delimited` variant is used.
In other words, `MacArgs` is used in two quite different places due to them
having partial overlap. I find this makes the code hard to read. It also leads
to various unreachable code paths, and allows invalid values (such as
accidentally using `MacArgs::Empty` in a `MacCall`).
This commit splits `MacArgs` in two:
- `DelimArgs` is a new struct just for the "delimited arguments" case. It is
now used in `MacCall` and `MacroDef`.
- `AttrArgs` is a renaming of the old `MacArgs` enum for the attribute macro
case. Its `Delimited` variant now contains a `DelimArgs`.
Various other related things are renamed as well.
These changes make the code clearer, avoids several unreachable paths, and
disallows the invalid values.
Add new lint [`misnamed-getters`]
```
changelog: Add new lint [`misnamed-getters`]
```
Closes#9769
The current lint matches all methods with a body of just one expression under the form `(&mut?)? <expr>.field` where field doesn't match the name of the method but there is a field of the same type in `<expr>` that matches the name. This allows matching nested structs, for example for newtype wrappers. This may cast the net a bit too wide and cause false positives. I'll run [clippy_lint_tester](https://github.com/mikerite/clippy_lint_tester) on the top crates to see how frequently false positives happen.
There also may be room for improvement by checking that the replacement field would work taking into account implementations of `Deref` and `DerefMut` even if the types don't exactly match but I don't know yet how this could be done.
Add `PolyExistentialPredicate` type alias
Wrapping `ExistentialPredicate`s in a binder is very common, and this alias already exists for the `PolyExistential{TraitRef,Projection}` types.
[arithmetic-side-effects] Detect overflowing associated constants of integers
Triggers the negation of maximum unsigned integers using associated constants. Rustc already handles `-128i8` but doesn't handle `-i8::MAX`.
At the same time, allows stuff like `-1234`.
changelog: FP: [arithmetic-side-effects] Detect overflowing associated constants of integers
Keep original literal notation in suggestion
While I did some investigation of https://github.com/rust-lang/rust-clippy/issues/9866 (I couldn't reproduce it though) I found that `unused_rounding` formats as follows:
```rust
3.0_f64.round() // => 3.0f64
```
This PR makes them preserve as the original notation.
```rust
3.0_f64.round() // => 3.0_f64
```
changelog: Suggestion Enhancement: [`unused_rounding`]: The suggestion now preserves the original float literal notation
Improve spans for RPITIT object-safety errors
No reason why we can't point at the `impl Trait` that causes the object-safety violation.
Also [drive-by: Add is_async fn to hir::IsAsync](c4165f3a96), which touches clippy too.
Return multiple resolutions from `def_path_res`
Changes `def_path_res` to return all the resolutions matching the path rather than the first one (with a namespace hint that covered some cases). This would fix any issues that come up with multiple versions of the same crate being present as they all have the same crate name
It also adds resolution of `impl _ {}` items for local items, and removes struct field resolution as it didn't seem to be used anywhere
I tested it on a local crate and it worked for the multiple crate issue, but I couldn't come up with a test that worked well with `// aux-build`, maybe `// aux-crate` after https://github.com/rust-lang/rust/pull/103266 could work but I'm not sure on that either
changelog: [`disallowed_methods`], [`disallowed_types`], [`disallowed_macros`]: fix path resolution with multiple versions of the same crate
changelog: [`disallowed_methods`]: Resolve methods in `impl`s in the current crate
Rollup of 8 pull requests
Successful merges:
- #101162 (Migrate rustc_resolve to use SessionDiagnostic, part # 1)
- #103386 (Don't allow `CoerceUnsized` into `dyn*` (except for trait upcasting))
- #103405 (Detect incorrect chaining of if and if let conditions and recover)
- #103594 (Fix non-associativity of `Instant` math on `aarch64-apple-darwin` targets)
- #104006 (Add variant_name function to `LangItem`)
- #104494 (Migrate GUI test to use functions)
- #104516 (rustdoc: clean up sidebar width CSS)
- #104550 (fix a typo)
Failed merges:
- #104554 (Use `ErrorGuaranteed::unchecked_claim_error_was_emitted` less)
r? `@ghost`
`@rustbot` modify labels: rollup
Extend `needless_borrowed_reference` to structs and tuples, ignore _
changelog: [`needless_borrowed_reference`]: Lint struct and tuple patterns, and patterns containing `_`
Now lints patterns like
```rust
&(ref a, ref b)
&Tuple(ref a, ref b)
&Struct { ref a, ref b }
&(ref a, _)
```
Add variant_name function to `LangItem`
Clippy has an internal lint that checks for the usage of hardcoded def paths and suggests to replace them with a lang or diagnostic item, if possible. This was implemented with a hack, by getting all the variants of the `LangItem` enum and then index into it with the position of the `LangItem` in the `items` list. This is no longer possible, because the `items` list can't be accessed anymore.
Follow up to #103603
cc `@camsteffen`
r? `@oli-obk`
This is blocking the sync between Clippy and Rust. I'm not sure if this is the best solution here, or if I should add a method `items()` to `LanguageItems` and keep the code in Clippy unchanged.
Fix typo in `expect_used` and `unwrap_used` warning messages
"\`an Option\`" -> "an \`Option\`" and "\`a Result\`" -> "a \`Result\`".
changelog: fix typo in `expect_used` and `unwrap_used` warning messages
`never_loop`: don't emit AlwaysBreaks if it targets a block
ref: https://github.com/rust-lang/rust-clippy/pull/9837#issuecomment-1312788194
The previous fix (#9837) was too simple and ignored all break commands inside a labelled block, regardless of whether their destination was a labelled block or a loop. This fix tracks all the labelled blocks in scope to ensure that only breaks targeting loops are considered.
changelog: [`never_loop`]: prevent false negatives from `breaks` nested in labelled blocks
Convert predicates into Predicate in the Obligation constructor
instead of having almost all callers do that.
This reduces a bit of boilerplate, and also paves the way for my work towards https://github.com/rust-lang/compiler-team/issues/531 (as it makes it easier to accept both goals and clauses where right now it only accepts predicates).
Clippy has an internal lint that checks for the usage of hardcoded def
paths and suggests to replace them with a lang or diagnostic item, if
possible. This was implemented with a hack, by getting all the variants
of the `LangItem` enum and then index into it with the position of the
`LangItem` in the `items` list. This is no longer possible, because the
`items` list can't be accessed anymore.
Record `LocalDefId` in HIR nodes instead of a side table
This is part of an attempt to remove the `HirId -> LocalDefId` table from HIR.
This attempt is a prerequisite to creation of `LocalDefId` after HIR lowering (https://github.com/rust-lang/rust/pull/96840), by controlling how `def_id` information is accessed.
This first part adds the information to HIR nodes themselves instead of a table.
The second part is https://github.com/rust-lang/rust/pull/103902
The third part will be to make `hir::Visitor::visit_fn` take a `LocalDefId` as last parameter.
The fourth part will be to completely remove the side table.
When we run `cargo test` in `clippy_lints` directory, it will generate
`foo.txt` in the directory.
In order to avoid that, add `no_run` to rustdoc which contains
`File::create`.
Introduced an ignored_ids parameter.
Takes O(n^2) time in the worst case.
Can be changed to collect block ids in first phase,
and then filter with binary search in second.
Instead of `ast::Lit`.
Literal lowering now happens at two different times. Expression literals
are lowered when HIR is crated. Attribute literals are lowered during
parsing.
This commit changes the language very slightly. Some programs that used
to not compile now will compile. This is because some invalid literals
that are removed by `cfg` or attribute macros will no longer trigger
errors. See this comment for more details:
https://github.com/rust-lang/rust/pull/102944#issuecomment-1277476773
feat: lint unchecked subtraction of a 'Duration' from an 'Instant'
Hello all, I tried to tackle the open issue #9371 and this is what I came up with.
I have a difficulty currently - some tests are failing:
```
failures:
[ui] ui/manual_instant_elapsed.rs
```
The `manual_instant_elapsed` is failing because of `Instant::now() - duration` test, this now gets also picked by `unchecked_duration_subtraction` lint.
What is the correct way to proceed in this case? Simply update the `.stderr` file for `manual_instant_elapsed` lint?
changelog: [`unchecked_duration_subtraction`]: Add lint for unchecked subtraction of a `Duration` from an `Instant`.
fixes#9371
