new_ret_no_self: allow Self in inner type for impl Trait return types
Check the inner types of associated types of a trait when checking for Self in the return type of a `new` method. This means that the following will no longer warn:
```rust
trait Trait {
type Inner;
}
struct S;
impl S {
fn new() -> impl Trait<Inner = Option<Self>> {
struct TraitImpl;
impl Trait for TraitImpl {
type Inner = Option<S>;
}
TraitImpl
}
}
```
```rust
#![feature(async_await)]
struct Connection;
impl Connection {
async fn new() -> Result<Self, ()> {
Ok(S)
}
}
```
closes#4359
changelog: fix `new_ret_no_self` lint for async `new` functions.
Don't emit enum_variant_names if remainder starts with a numeric
changelog: Fix false positive in `pub_enum_variant_names` and `enum_variant_names`
As [per the reference](https://doc.rust-lang.org/reference/identifiers.html), identifiers must start with a letter. So we don't suggest a better
variant naming in case the remainder would start with a numeric.
Fixes#739
Add negation to `len_zero` lint to show more explicit message.
Fixes#4304 I have updated the `len_zero` to show the required negation in case of like the below case.
```
fn main() {
let v = vec![1];
if v.len() > 0 {
}
}
```
changelog: Clarify suggestion of `len_zero` lint.
Fix `for on` typo
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closes#4317
changelog: minor typo fix
Mark `fn_to_numeric_cast` lints as MaybeIncorrect
At least for now so that `cargo fix --clippy` is not causing problems
with this lint. See #3896 for the remaining problems with the suggestions of this lint.
changelog: none
cc #3630, #3896
trait bounds lint - repeated types
This PR is to tackle https://github.com/rust-lang/rust-clippy/issues/3764 it's still a WIP and doesn't work but this is an initial stab. It builds though I haven't added any tests as I'm not sure where lint tests should go?
Unfortunately, it seems id isn't tied to the type itself but I guess where it is in the AST? Looking at https://manishearth.github.io/rust-internals-docs/syntax/ast/struct.Ty.html I can't see any members that would let me tell if a type was repeated in multiple trait bounds.
There may be other issues with how I've implemented this so any assistance is appreciated!
changelog: Add new lint: `type_repetition_in_bounds`
This lint adds warning if types are redundantly repeated in trait bounds i.e. `T: Copy, T: Clone` instead of `T: Copy + Clone`. This is a late pass trait lint and has necessitated the addition of code to allow hashing of TyKinds without taking into account Span information.
Ignore generated fresh lifetimes in elision check
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fixes#3988
changelog: Ignore generated fresh lifetimes in elision check.
**HELP**: It seems `tests/ui` are compiled under edition 2015, and I don't know how to add tests for this properly.
Here is the test input it had already passed:
```rust
#![feature(async_await)]
#![allow(dead_code)]
async fn sink1<'a>(_: &'a str) {} // lint
async fn sink1_elided(_: &str) {} // ok
async fn one_to_one<'a>(s: &'a str) -> &'a str { s } // lint
async fn one_to_one_elided(s: &str) -> &str { s } // ok
async fn all_to_one<'a>(a: &'a str, _b: &'a str) -> &'a str { a } // ok
// async fn unrelated(_: &str, _: &str) {} // Not allowed in async fn
// #3988
struct Foo;
impl Foo {
pub async fn foo(&mut self) {} // ok
}
// rust-lang/rust#61115
async fn print(s: &str) { // ok
println!("{}", s);
}
fn main() {}
```
false positives fixes of `implicit_return`
- Handle returning macro statements properly (remove "this error originates in a macro outside of the current crate")
- Handle functions that return never type
- Handle functions that panic but do not return never type
changelog: Fix false positives in `implicit_return` lint pertaining to macros and panics
Fix bug in `implicit_hasher` causing crashes
Skip linting if the type is from an external macro. Closes#4260.
changelog: Fix bug in `implicit_hasher` causing crashes
Improve cast_ptr_alignment lint
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* print alignment in bytes in the lint message
* ignore ZST left-hand types
Fixes#3797 and #4256
changelog:
* `cast_ptr_alignment`: Print alignment in bytes in the lint message
* `cast_ptr_alignment`: Ignore casting from ZST left-hand types
Avoid reporting string_lit_as_bytes for long strings
Port of @jens1o code ([b76f939][jens1o_commit])
Fixes#1208
[jens1o_commit]: b76f939ac2
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changelog: bugfix for long strings as bytes
make needless_return work with void functions
fixes https://github.com/rust-lang/rust-clippy/issues/4181.
changelog: make needless_return work with void functions.
I don't think the failure is related to my changes, but I'm not sure 🤔
Downgrade integer_division to restriction
I believe that this lint falls outside of the scope of opinionated pedantism of the other pedantic lints.
changelog: Downgrade integer_division lint from pedantic to restriction
lint does not trigger when there is a difference in mutability
lint does not trigger when the method belongs to a trait which is not implemebted directly (Deref)
Fixing eta with respect to lazy evaluation.
This fixes#4187
changelog: `redundant_closure`: stop linting on expressions returning a function, which is then directly used by the closure
Add example to needless_range_loop
adds a "could be written as" example
btw, is it correct that the lint triggers even if the index is used not just for getting the values by index?
So that I have to add `.iter().enumerate()` to still get an index?
changelog: none
trivially_copy_pass_by_ref: print size of type and limit in the lint message
changelog: trivially_copy_pass_by_ref: print size of type and limit in the lint message
Fix match_same_arms to fail late
Changes:
- Add a function search_same_list which return a list of matched expressions
- Change the match_same_arms implementation behavior. It will lint each same arms found.
fixes#4096
changelog: none
Implement "Use last" lint
Closes#3673
This lint checks the use of `x.get(x.len() - 1)` and suggests `x.last()` (where `x` is a `Vec`).
There's at least one more thing that needs to happen here. I believe I am correctly checking most of the scenarios and avoiding false positives. However, if different `Vec`s are used for the `x.get` and `y.len`, then it will emit a false positive. In other words, I need to check to make sure the `Vec`s are the same.
Also, a lot of these commits were temporary and not helpful to the project history...am I supposed to squash on merge? If so, how do I do that?
changelog: New lint: `get_last_with_len`
Added lint for TryFrom for checked integer conversion.
works towards #3947
Added lint for try_from for checked integer conversion.
Should recognize simple & straight-forward checked integer conversions.
Changes:
- Add a function search_same_list which return a list of matched expressions
- Change the match_same_arms implementation behaviour. It will lint each same arms found.
Move the method checking into a new lint called
`redundant_closures_for_method_calls` and put it in the pedantic group.
This aspect of the lint seems more controversial than the rest.
cc #3942
Fix#4033 search_is_some
Fixes#4033.
Suggest `any(|x| ..)` instead of `any(|&x| ..)` for `find(|&x| ..).is_some()` (Lint [search_is_some](https://rust-lang.github.io/rust-clippy/master/index.html#search_is_some))
FnDecl of `find`:
```rust
fn find<P>(&mut self, mut p: P) -> Option<Self::Item> where
P: FnMut(&Self::Item) -> bool
```
FnDecl of `any`:
```rust
fn any<F>(&mut self, mut f: F) -> bool where
F: FnMut(Self::Item) -> bool
```
If match on `|&_|` in closure of `find`, only use `|_|` in the suggestion.
PS. It's the first time that I have used the `hir` API, please correct me if there is any mistake 😺
useless_let_if_seq handle interior mutability
fixes#3043
This passes all tests, including a new one specifically dealing with a type with interior mutability. The main thing I'm unsure of is whether the span I used in the call to `is_freeze` is the most appropriate span to use, or if it matters.
Do not trigger redundant_closure for non-function types
fixes#3898
Added a check for the entity being called in the closure body to be a FnDef. This way lint does not trigger for ADTs (Box) but I'm not sure if it's correct and not too restrictive.
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changelog: Fix false positive in `redundant_closure` pertaining to non-function types
Ignore non-const ctor expressions in or_fn_call
Fixes https://github.com/rust-lang/rust-clippy/issues/1338
Should have been fixed by #919, however that focuses on const ctor expressions only, and `.or(Some(local))` isn't const.
This also automatically ignores things like `.or(Some(local.clone())` which we don't actually want to do; I need to figure out what to do here.
changelog: Fixed false positive in [`or_fn_call`] pertaining to enum variant constructors
r? @oli-obk @phansch
Allow allowing of toplevel_ref_arg lint
I'm not sure why some lints need the `HirId` to be able to recognize the
lint level attributes, but this commit makes the lint level attributes
work for `toplevel_ref_arg`.
Fixes#2332
changelog: Allow allowing of `toplevel_ref_arg` lint
Fix false positive in module_name_repetitions lint
This lint was triggering on modules inside expanded attrs, like
for example `#[cfg(test)]` and possibly more.
It was not reporting a location in #3892 because `span.lo()` and `span.hi()` both were 0.
Fixes#3892
changelog: Fix false positive in `module_name_repetitions` lint
I'm not sure why some lints need the `HirId` to be able to recognize the
lint level attributes, but this commit makes the lint level attributes
work for `toplevel_ref_arg`.
Change naive_bytecount applicability to MaybeIncorrect
We can't use `MachineApplicable` here as applying the fix will cause
another error because `bytecount` would first have to be added to the
Cargo.toml.
Example:
```
error: You appear to be counting bytes the naive way
--> $DIR/bytecount.rs:5:13
|
LL | let _ = x.iter().filter(|&&a| a == 0).count(); // naive byte count
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Consider using the bytecount crate: `bytecount::count(x, 0)`
```
Just replacing it with the suggestion is not enough.
cc #3630
Change while_let_loop applicability to HasPlaceholders
The suggestion has been changed at some point to use `..` in the suggested code.
Due to that we can't make the lint MachineApplicable anymore.
cc #3630
This was causing two different ICEs in #3741.
The first was fixed in #3925.
The second one is fixed with this commit: We just don't `expect`
anymore. If the snippet doesn't contain an `else`, we stop emitting the
lint because it's not a suspiciously formatted else anyway.
Fix ICE in decimal_literal_representation lint
Handling the integer parsing properly instead of just unwrapping.
Note that the test is not catching the ICE because plain UI tests
[currently hide ICEs][compiletest_issue]. Once that issue is fixed, this
test would fail properly again.
Fixes#3891
[compiletest_issue]: https://github.com/laumann/compiletest-rs/issues/169
Handling the integer parsing properly instead of just unwrapping.
Note that the test is not catching the ICE because plain UI tests
[currently hide ICEs][compiletest_issue]. Once that issue is fixed, this
test would fail properly again.
[compiletest_issue]: https://github.com/laumann/compiletest-rs/issues/169
Fix `explicit_counter_loop` suggestion
#1670
This code seems to me to work, but I have two question.
* Because range expression desugared in hir, `Sugg::hir` doesn't add parenthesis to range expression. Which function is better to check range do you think, `check_for_loop_explicit_counter` or `hir_from_snippet`?
* Do you think we need to distinguish between range expression and struct expression that creates `std::ops::Range*`?
* Late Lint pass, catches:
* One liner: 0 -> null -> transmute
* One liner: std:null() -> transmute
* Const (which resolves to null) -> transmute
* UI Test case for Lint
* Updated test for issue 3849, because now the lint that code generated is in Clippy.
* Expanded `const.rs` miri-based Constant Folding code, to cover
raw pointers
Add `doc(include = ...)` detection to `missing_docs_in_private_items`
The whole `missing documentation in crate` part doesn't have any tests. If I should add test cases tell me.
Fix `boxed_local` suggestion
Don't warn about an argument that is moved into a closure.
ExprUseVisitor doesn't walk into nested bodies so use a new
visitor that collects the variables that are moved into closures.
Fixes#3739
Refactor: Cleanup one part of assign_ops lint
Removes a lot of indentation and separates lint emission from lint
logic. Only touches the `hir::ExprKind::AssignOp` part of the lint.
Refactor: Extract `trait_ref_of_method` function
This pattern was used in three places after #3844, so I think it's worth moving it into `utils/mod.rs` and documenting it.
* Ran automatic naming update
* Formalized rename of `cyclomatic_complexity` to `cognitive_complexity`
** Added the rename to `lib.rs`
** Added rename test
* Added warning for deprecated key `cyclomatic_complexity_threshold` and tests for it
* Added deprecation status for Clippy's builtin attribute
* Updated tests for new builtin attribute renaming
Fix `bool_comparison` with non-`bool` expressions
Fixes#3703.
It just moves around the type check that was already there for some comparison to all of them, because if one type isn't `bool`, none of those comparison can be simplified.
Fix ICE #3719+#3718 in lint match_ref_pats
Fixes#3719
This conveniently also fixes#3718
The ICE occurs when the match expression was a macro call, where the macro was defined in another file. Since we don't have the ability to reproduce this behavior with our UI tests (AFAIK), I couldn't add a test reproducing this ICE.. However, I added a test which is related to the ICE, to show the new behavior of the lint.
I tested it with the mscheme repo locally and the ICE didn't happen anymore.
r? @matthiaskrgr
Fix ICE #3747
I'm not sure if this was the correct approach.
I don't know if I put tests/ui/crashses/ice-3747.rs in correct place because the test always passed when I ran it with `cargo test`, even without the fix applied.
If I run that test with `env CLIPPY_TESTS=true cargo run --bin clippy-driver -- -L ./target/debug tests/ui/crashes/ice-3747.rs` then the test correctly fails without the fix applied
fixes#3747
Extract diagnostics module and document some functions
This moves the lint building functions from `utils/mod.rs` to their own
`utils/diagnostics.rs` file. Also adds documentation for three of them.
Make needless_range_loop not applicable to structures without iter method
Fixes https://github.com/rust-lang/rust-clippy/issues/3788
Now we will start lint indexed structure only if it has known iter or iter_mut method implemented.
Don't warn about an argument that is moved into a closure.
ExprUseVisitor doesn't walk into nested bodies so use a new
visitor that collects the variables that are moved into closures.
Fixes#3739
Don't check [print/write]_with_newline on raw strings
Some tests for #3778 and some maybe-not-the-greatest code that passes those tests!
I didn't run `fmt` because a) it doesn't seem to install on nightly for me, and b) on stable it wanted to apply formatting to over 90 files. Happy to make any tweaks though!
I suspect this contribution may require more than just tweaks. I'm still sort of new to rust so it may not be idiomatic, and the specific approach I took feels a little heavy-handed and brittle. I'm happy to make changes with some guidance, or equally happy if this gives a starting place for someone else to do it better :)
Add a lint to warn on `T: Drop` bounds
**What it does:** Checks for generics with `std::ops::Drop` as bounds.
**Why is this bad?** `Drop` bounds do not really accomplish anything.
A type may have compiler-generated drop glue without implementing the
`Drop` trait itself. The `Drop` trait also only has one method,
`Drop::drop`, and that function is by fiat not callable in user code.
So there is really no use case for using `Drop` in trait bounds.
**Known problems:** None.
**Example:**
```rust
fn foo<T: Drop>() {}
```
Fixes#3773
Both regular strings and raw strings can contain literal newlines. This commit
extends the lint to also warn about terminating strings with these.
Behaviour handling for raw strings is also moved into `check_newlines` by
passing in the `is_raw` boolean from `check_tts` as
[suggested](https://github.com/rust-lang/rust-clippy/pull/3781#pullrequestreview-204663732)
Pass tests for #3778, {print,write}_with_newline false positive
This change guards the lint from checking newlines with a sort of complicated
check to see if it's a raw string. Raw strings shouldn't be newline-checked,
since r"\n" is literally \-n, not a newline. I think it's ok not to check for
_literal_ newlines at the end of raw strings, but maybe that's debatable.
I... don't think this code is that great. I wanted to write the check after
`check_tts`, but that was too late -- raw string type info is lost (or I
couldn't find it). Putting it inside `check_tts` feels heavy-duty and the check
itself feels like a brittle reach possibly into places it shouldn't.
Maybe someone can fix this up :)
**What it does:** Checks for generics with `std::ops::Drop` as bounds.
**Why is this bad?** `Drop` bounds do not really accomplish anything.
A type may have compiler-generated drop glue without implementing the
`Drop` trait itself. The `Drop` trait also only has one method,
`Drop::drop`, and that function is by fiat not callable in user code.
So there is really no use case for using `Drop` in trait bounds.
**Known problems:** None.
**Example:**
```rust
fn foo<T: Drop>() {}
```
Fix ICE in needless_pass_by_value lint
If I understand it correctly, we were first creating a type with a
`RegionKind::ReErased` region and then deleted it again in
`util::implements_trait` with:
cx.tcx.erase_regions(&ty);
causing the type query to fail.
It looks like using `ReEmpty` works around that deletion.
Fixes#3144
Macro check for assertion_on_constants lint
The `assertion_on_constants` lint currently has following output for this code [Playground](https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=6f2c9df6fc50baf847212d3b5136ee97):
```rust
macro_rules! assert_const {
($len:expr) => {
assert!($len > 0);
}
}
fn main() {
assert_const!(3);
assert_const!(-1);
}
```
```
warning: assert!(const: true) will be optimized out by the compiler
--> src/main.rs:3:9
|
3 | assert!($len > 0);
| ^^^^^^^^^^^^^^^^^^
...
8 | assert_const!(3);
| ---------------- in this macro invocation
|
= note: #[warn(clippy::assertions_on_constants)] on by default
= help: remove it
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#assertions_on_constants
warning: assert!(const: false) should probably be replaced
--> src/main.rs:3:9
|
3 | assert!($len > 0);
| ^^^^^^^^^^^^^^^^^^
...
9 | assert_const!(-1);
| ----------------- in this macro invocation
|
= help: use panic!() or unreachable!()
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#assertions_on_constants
```
This is contradictory. This lint should not trigger if the `assert!` is in a macro itself.
Add a uitest subcommand to simplify UI test invocation
This makes running single tests a lot easier.
It's now
`TESTNAME=xxx cargo uitest`
instead of
`TESTNAME=xxx cargo test --test compile-test`
Start making clippy easier to invoke in non-cargo contexts
Clippy (clippy-driver) currently has a couple of strong but unnecessary couplings with cargo. This series:
1. makes detection of check builds more robust, and
2. make clippy-driver use the --sysroot specified on the command line as its internal sysroot.
If I understand it correctly, we were first creating a type with a
`RegionKind::ReErased` region and then deleted it again in
`util::implements_trait` with:
cx.tcx.erase_regions(&ty);
causing the type query to fail.
It looks like using `ReEmpty` works around that deletion.
Fix `cast_sign_loss` false positive
This checks if the value is a non-negative constant before linting about
losing the sign.
Because the `constant` function doesn't handle const functions, we check if
the value is from a call to a `max_value` function directly. A utility method
called `get_def_path` was added to make checking for the function paths
easier.
Fixes#2728
The rustc change added HirId to a few nodes. As I understand it, the plan is
to remove the NodeId from these nodes eventually. Where the NodeId was
not being matched, I used `..` to try and avoid further breakage. Where it
was, I used `_` to make the fix easier when NodeId is removed.
Adding lint test for excessive LOC.
This is a WIP for #2377. Just wanted to pull in because I had a few questions:
1. Is it okay that I'm approaching this via counting by looking at each line in the snippet instead of looking at the AST tree? If there's another way to do it, I want to make sure I'm doing the correct way, but I wasn't sure since the output AST JSON doesn't seem to contain whitespace.
2. My function is definitely going to trigger the lint, so also wanted to see if there was something obvious I could do to reduce it.
3. Are the two tests fine, or is there something obvious I'm missing?
4. Obviously bigger question - am I approaching the line count correctly. Current strategy is count a line if it contains some code, so skip if it's just comments or empty.
`hir::Ty` doesn't seem to know anything about type bounds and
`cx.tcx.type_of(def_id)` caused an ICE when it was passed a generic type
with a bound:
```
src/librustc_typeck/collect.rs:1311: unexpected non-type Node::GenericParam: Type { default: None, synthetic: None }
```
Converting it to a proper `Ty` fixes the ICE and catches a few more
places where the lint applies.
This checks if the value is a non-negative constant before linting about
losing the sign.
Because the `constant` function doesn't handle const functions, we check if
the value is from a call to a `max_value` function directly. A utility method
called `get_def_path` was added to make checking for the function paths
easier.
Fixes#2728
Add initial version of const_fn lint
This adds an initial version of a lint that can tell if a function could be `const`.
TODO:
- [x] Finish up the docs
- [x] Fix the ICE
cc #2440
Prevent incorrect cast_lossless suggestion in const_fn
`::from` is not a const fn, so applying the suggestion of
`cast_lossless` would fail to compile. The fix is to skip the lint if
the cast is found inside a const fn.
Fixes#3656
Fix documentation for `slow_vector_initialization`
This PR fixes the documentation for the lint `slow_vector_initialization`. The documentation recommended writing `vec![len; 0]` but the correct solution is `vec![0; len]`.
for file in `fd \.rs$` ; do sed -i s/span_suggestion_with_applicability/span_suggestion/g $file ; done
for file in `fd \.rs$` ; do sed -i s/span_suggestion_short_with_applicability/span_suggestion_short/g $file ; done
for file in `fd \.rs$` ; do sed -i s/span_suggestions_with_applicability/span_suggestions/g $file ; done
Fix `expect_fun_call` lint suggestions
This commit corrects some bad suggestions produced by the
`expect_fun_call` lint and enables `rust-fix` checking on the tests.
Addresses #3630
`::from` is not a const fn, so applying the suggestion of
`cast_lossless` would fail to compile. The fix is to skip the lint if
the cast is found inside a const fn.
* master: (58 commits)
Rustfmt all the things
Don't make decisions on values that don't represent the decision
Improving comments.
Rustup
Added rustfix to the test.
Improve span shortening.
Added "make_return" and "blockify" convenience methods in Sugg and used them in "needless_bool".
Actually check for constants.
Fixed potential mistakes with nesting. Added tests.
formatting fix
Update clippy_lints/src/needless_bool.rs
formatting fix
Fixing typo in CONTRIBUTING.md
Fix breakage due to rust-lang/rust#57651
needless bool lint suggestion is wrapped in brackets if it is an "else" clause of an "if-else" statement
Fix automatic suggestion on `use_self`.
Remove negative integer literal checks.
Fix `implicit_return` false positives.
Run rustfmt
Fixed breakage due to rust-lang/rust#57489
...
Fix automatic suggestion on `use_self`.
In an example like this:
```rust
impl Example {
fn fun_1() { }
fn fun_2() {
Example::fun_1();
}
}
```
Clippy tries to replace `Example::fun_1` with `Self`, loosing `::fun_1` in the process, it should rather try to replace `Example` with `Self`.
**Question**
- There may be other paths that need the same treatment, but I'm not sure I understand them fully:
- e648adf086/clippy_lints/src/use_self.rs (L94-L96)
- e648adf086/clippy_lints/src/use_self.rs (L225-L229)
Fix `implicit_return` false positives.
Fixes the following false positives:
- linting on `if let` without `else` in a `loop` even with a present `return`
- linting on `unreachable!()`
Catch up with `format_args` change
Catches up with a change in rust-lang/rust#57537. (Since the optimization is optional, this clippy PR can be merged before the rustc PR.)
Happened to fix a bug in `expect_fun_call`, that is the lint ignores more than
one arguments to `format`.
```
warning: use of `expect` followed by a function call
--> src/main.rs:2:17
|
2 | Some("foo").expect(format!("{} {}", 1, 2).as_ref());
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|| panic!("{} {}", 1))`
|
```
Catches up with a change in rust-lang/rust#57537
Happened to fix a bug in `expect_fun_call`, that is the lint ignores more than
one arguments to `format`.
`cloned` requires that the elements of the iterator must be references. This
change determines if that is the case by examining the type of the closure
argument and suggesting `.cloned` only if it is a reference. When the closure
argument is not a reference, it suggests removing the `map` call instead.
A minor problem with this change is that the new check sometimes overlaps
with the `clone_on_copy` lint.
Fixes#498
Add several run rustfix annotations
Adds `run-rustfix` to 18 of the tests from the tracking issue #3630.
Each test has its own commit, to make reviewing easier (hopefully this is easier to review than 18 separate PRs).
## Changes
- `cfg_attr_rustfmt`: Custom inner attributes are unstable. Let's disable the lint for inner attributes until [#54726](https://github.com/rust-lang/rust/issues/54726) stabilizes
- `collapsible_if`: unrelated cyclomatic_complexity warning that can be ignored
- `duration_subsec`: Simply needed `#![allow(dead_code)]`
- `excessive_precision`: Fixed by `#!allow(dead_code,unused_variables)`
- `explicit_write`: Fixed by `#![allow(unused_imports)]`
- `inconsistent_digit_grouping`: Avoid triggering `clippy::excessive_precision` lint
- `infallible_destructuring_match`: Fixed by `#![allow(dead_code, unreachable_code, unused_variables)]`
- `into_iter_on_ref`: Triggered unrelated `clippy::useless_vec` lint
- `large_digit_groups`: Avoid triggering `clippy::excessive_precision` lint
- `map_clone`: Fixed by `#![allow(clippy::iter_cloned_collect)]`
- `mem_replace`: Suggestion causes import to be unused, fixed by `#![allow(unused_imports)]`
- `precedence`: Allow some unrelated lints, and change out-of-range `0b1111_1111i8` literal
- `redundant_field_names`: Allow dead code, and remove stabilized feature toggles
- `replace_consts`: Fixed by `#![allow(unused_variables)]`
- `starts_ends_with`: Fixed by `#![allow(unused_must_use)]`
- `types`: Fixed by `#![allow(dead_code, unused_variables)]`
- `unit_arg`: Fixed by `#[allow(unused_must_use)]`
- `unnecessary_fold`: Fixed by adding type annotations and adding `#![allow(dead_code)]`
Restrict `use_self` on nested items
Fixes#3637Fixes#3463
These changes make it so that nested items aren't visited any more by the `use_self` lint.
I think visiting nested items should be possible (so that it uses a different `item_path` for the nested item), but I'm not sure whether it's viable and what the best approach would be.
- Can `item_path` be changed to a new `Self` path before visiting the item, and then changing it back afterwards?
- Alternatively, could a new visitor be created, re-using `check_trait_method_impl_decl`?
cast_ref_to_mut lint
I see this pattern way too often, and it's completely wrong. In fact, due to how common this incorrect pattern is, [the Rustonomicon specifically points this out](https://doc.rust-lang.org/nomicon/transmutes.html).
> - Transmuting an & to &mut is UB
> - Transmuting an & to &mut is always UB
> - No you can't do it
> - No you're not special
This is my first lint.
Trigger `use_self` lint in local macros
Closes#2098
The test currently only covers local macros. #2098 suggested this:
> You could add the macro in question into the `mini_macro` subcrate
But that doesn't work for a `macro_rules`:
```
error: cannot export macro_rules! macros from a `proc-macro` crate type currently
```
So I suggest leaving out the test for external macros, as using `in_external_macro` seems straigtforward enough. Alternatives would be to use to add an additional crate (overkill if you ask me), or test with a `proc-macro`.
Integrate rustfix into Clippy test suite
Once the [PR to compiletest-rs](https://github.com/laumann/compiletest-rs/pull/151) is reviewed and merged this fixes#2376.
I will create a separate tracking issue for adding `run-rustfix` to all tests.
Only trigger `infinite_iter` lint for infinitely allocating `collect()` calls
Fixes #3538
~Oh, I guess this should actually check other methods like `count` as well, not only `collect()`.~
Never mind, `collect` is the only of these functions that allocates a data structure.
Fix if_same_then_else false positive
This fixes false positive in #3559.
The problem was that `SpanlessEq` does not check patterns in declarations. So this two blocks considered equal.
```rust
if true {
let (x, y) = foo();
} else {
let (y, x) = foo();
}
```
Not sure if the proposed change is safe as `SpanlessEq` is used extensively in other lints, but I tried hard to come up with counterexample and failed.
Merge new_without_default_derive into new_without_default
Closes#3525, deprecating new_without_default_derive and moving both lints into new_without_default.
Fix false positives for `implicit_return` and `empty_loop` on macro expansion.
This PR only fixes `implicit_return` and `empty_loop`.
But I suspect this bug may affect a lot of other lints.
Teach `suspicious_else_formatting` about `if .. {..} {..}`
We essentially treat bare blocks `{..}` identically to `if .. {..}`, except for different lint messages.
Fixes#3044
Implements lint for order comparisons against bool (#3438)
As described on issue #3438, this change implements linting for `>` and `<` comparisons against both `boolean` literals and between expressions.
Adds lint for Vec<Box<T: Sized>>
This adds, and subsequently closes#3530. This is the first time I've ever worked with anything remotely close to internal Rust code, so I'm very much unsure about the if_chain! to figure this out!
I can't get rustfmt working on WSL with nightly 2018-12-07:
`error: component 'rustfmt' for target 'x86_64-unknown-linux-gnu' is unavailable for download`
Lint redundant clone of fields
Makes `redundant_clone` warn on unnecessary `foo.field.clone()` sometimes (it can detect an unnecessary clone only if the base of projection, `foo` in this case, is not used at all after that). This is enough for cases like `returns_tuple().0.clone()`.
If there are more than one such assignment, the last one may be
the one supplied to `clone` method.
Makes `find_stmt_assigns_to` internally reverses the iterator to make
the intent to "iterate statements backward" clear.
The path of `libc::c_void` has changes in 5c1a6b8a6d
The DefId path is now always platform specific like
`libc::windows::c_void`. This fixes our c_void detection to only check
the first and last elements.
This now only checks for wildcard_dependencies if the source is a
non-git source.
I tried adding a compiletest suite for the cargo lints, but I was unable
to override the `Cargo.toml` of the original executable.
I tested this manually by modifying the main `Cargo.toml`.
Fixes#3458
I believe if the user already decided to put underscores in their
literal, Clippy should be willing to believe that they put a number of
underscores that they felt was readable.
This lint looks for:
let mut vec = Vec::with_capacity(len);
vec.set_len(len);
The suggested replacement is `vec![0; len]`.
This is far too opinionated to be a deny-by-default lint because the performance
characteristics of the suggested replacement are totally different.
I am not convinced that this lint has value beyond what deny(unsafe_code) gives
you. Unsafe code is unsafe but please don't deny-by-default lint it if that's
the only reason.
Warning was:
warning: the feature `macro_at_most_once_rep` has been stable since 1.32.0 and no longer requires an attribute to enable
--> clippy_lints/src/lib.rs:19:12
|
19 | #![feature(macro_at_most_once_rep)]
| ^^^^^^^^^^^^^^^^^^^^^^
|
= note: #[warn(stable_features)] on by default
Some bugs and some documentation is unrelated to the Applicability change, but
these bugs were serious and the documentation was kind of required to
understand what's going on.
Instead of searching for all the successive expressions after a vector
allocation, check only the first expression.
This is done to minimize the amount of false positives of the lint.
Add lint to detect slow zero-filled vector initialization. It detects
when a vector is zero-filled with extended with `repeat(0).take(len)`
or `resize(len, 0)`.
This zero-fillings are usually slower than simply using `vec![0; len]`.
I noticed that I suppress this lint in many of my projects.
https://github.com/search?q=needless_pass_by_value+user%3Adtolnay&type=Codehttps://github.com/search?q=needless_pass_by_value+user%3Aserde-rs&type=Code
Upon further inspection, this lint has a *long* history of false
positives (and several remaining).
Generally I feel that this lint is the definition of pedantic and should
not be linted by default.
#[derive(Debug)]
enum How {
ThisWay,
ThatWay,
}
// Are we really better off forcing the call sites to write f(&_)...?
fn f(how: How) {
println!("You want to do it {:?}", how);
}
fn main() {
f(How::ThatWay);
}
This finishes up the rewrite of `update_lints.py` in Rust. More
specifically, this
* adds the `--check` flag and handling to clippy_dev
* tracks file changes over the different calls to `replace_region_in_file`
* only writes changes to files if the `--check` flag is *not* used
* runs `./util/dev update_lints --check` on CI instead of the old script
* replaces usage of the `update_lints.py` script with an error
`./util/dev update_lints` behaves 99% the same as the python script.
The only difference that I'm aware of is an ordering change to
`clippy_lints/src/lib.rs` because underscores seem to be sorted
differently in Rust and in Python.
🏁
3353: float support added for mistyped_literal_suffixes lint r=mikerite a=Maxgy
I implemented the mistyped_literal_suffixes lint for float literals.
```
#![allow(unused_variables)]
fn main() {
let x = 1E2_32;
let x = 75.22_64;
}
```
Given the above, the additional check suggests the variables to be written as `let x = 1E2_f32` and `let x = 75.22_f64`.
Fixes#3167
Co-authored-by: Maxwell Anderson <maxwell.brayden.anderson@gmail.com>
`possible_missing_comma` should only trigger when the binary operator has
unary equivalent. Otherwise, it's not possible to insert a comma without
breaking compilation. The operators identified were `+`, `&`, `*` and `-`.
This fixes the specific examples given in issues #3244 and #3396
but doesn't address the conflict this lint has with the style of starting
a line with a binary operator.
3388: RIIR update lints: Generate deprecated lints r=phansch a=phansch
The update script now also generates the 'register_removed' section in
`clippy_lints/src/lib.rs`.
Also, instead of using `let mut store ...`, I added a new identifier
line so that the replacement will continue to work in case `let mut
store ...` ever changes.
cc #2882
Co-authored-by: Philipp Hansch <dev@phansch.net>
3368: added downsides to "known problems" for get_unwrap lint r=flip1995 a=humean
As a beginner I found this lint to be confusing because I was not sure how the `Option` type disappeared as conceptually I know that my `.get()` and Index could fail. Initially I thought maybe the compiler or clippy was smart enough to understand that it was impossible for my `.get()` to fail in this particular case, but it was explained to me that using the Index syntax is just shorthand for directly unwrapping the value:
https://doc.rust-lang.org/src/std/collections/hash/map.rs.html#1547
For beginners or users trying to iterate quickly it seems common to litter your code with `unwrap` or `except` as placeholders for where some explicit error handling might need to take place. I think it should be warned that using Index is merely more concise, but doesn't at all reduce the risk of panics and might in fact cause you to miss handling them in a future refactor.
Co-authored-by: Michael Rutter <michael.john.rutter@gmail.com>
Co-authored-by: Michael Rutter <humean@users.noreply.github.com>
The update script now also generates the 'register_removed' section in
`clippy_lints/src/lib.rs`.
Also, instead of using `let mut store ...`, I added a new identifier
line so that the replacement will continue to work in case `let mut
store ...` ever changes.
3217: Fix string_lit_as_bytes lint for macros r=phansch a=yaahallo
Prior to this change, string_lit_as_bytes would trigger for constructs
like `include_str!("filename").as_bytes()` and would recommend fixing it
by rewriting as `binclude_str!("filename")`.
This change updates the lint to act as an EarlyLintPass lint. It then
differentiates between string literals and macros that have bytes
yielding alternatives.
Closes#3205
3366: Don't expand macros in some suggestions r=oli-obk a=phansch
Fixes#1148Fixes#1628Fixes#2455Fixes#3023Fixes#3333Fixes#3360
Co-authored-by: Jane Lusby <jlusby42@gmail.com>
Co-authored-by: Philipp Hansch <dev@phansch.net>
Prior to this change, string_lit_as_bytes would trigger for constructs
like `include_str!("filename").as_bytes()` and would recommend fixing it
by rewriting as `binclude_str!("filename")`.
This change updates the lint to act as an EarlyLintPass lint. It then
differentiates between string literals and macros that have bytes
yielding alternatives.
Closes#3205
3355: Lint to remove redundant `clone()`s r=oli-obk a=sinkuu
This PR adds lint `redundant_clone`. It suggests to remove redundant `clone()` that clones a owned value that will be dropped without any usage after that.
Real-world example: https://github.com/rust-lang/rust/compare/7b0735a..sinkuu:redundant_clone2
Co-authored-by: Shotaro Yamada <sinkuu@sinkuu.xyz>
3331: Disable arithmetic lints in constant items r=oli-obk a=pengowen123
Currently this will not catch cases in associated constants. I'm not sure whether checking spans is the best way to solve this issue, but I don't think it will cause any problems.
Fixes#1858
Co-authored-by: Owen Sanchez <pengowen816@gmail.com>
3356: Fix warnings introduced by #3349 r=flip1995 a=flip1995
I missed these warnings during review, should have checked the Travis log first.
Co-authored-by: flip1995 <hello@philkrones.com>
3338: new_ret_no_self false positives r=flip1995 a=JoshMcguigan
~~WORK IN PROGRESS~~
I plan to fix all of the false positives in #3313 in this PR, but I wanted to open it now to start gathering feedback.
In this first commit, I've updated the lint to allow tuple return types as long as `Self` shows up at least once, in any position of the tuple. I believe this is the broadest possible interpretation of what should be allowed for tuple return types, but I would certainly be okay making the lint more strict.
fixes#3313
Co-authored-by: Josh Mcguigan <joshmcg88@gmail.com>
3349: Fixes#3347: Lint for wildcard dependencies in Cargo.toml r=ordovicia a=ordovicia
Add a lint for wildcard dependencies in Cargo.toml.
How should I write a test for this lint?
Fixes#3347
Co-authored-by: Hidehito Yabuuchi <hdht.ybuc@gmail.com>
3350: Don't emit `new_without_default_derive` if an impl of Default exists regardless of generics r=oli-obk a=pengowen123
Fixes#2226
Co-authored-by: Owen Sanchez <pengowen816@gmail.com>
3339: Check for known array length in `needless_range_loop` r=phansch a=HMPerson1
In `VarVisitor`, we now keep track of the type of the thing that was directly indexed and, if it's an array, check if the range's end is (or is past) the array's length.
Fixes #3033
Co-authored-by: HMPerson1 <hmperson1@gmail.com>
An ICE would occur if the needless range loop was triggered
within a procedural macro, because Clippy would try to produce
a code suggestion which was invalid, and caused the compiler
to crash.
This commit takes the same approach which Clippy currently takes
to work around this type of crash in the needless pass by value lint,
which is to skip the lint if Clippy is inside of a macro.
Methods like `Iterator::any` borrow the iterator mutably,
which is not allowed within a pattern guard and will fail to compile.
This commit prevents clippy from suggesting this type of change.
Closes#3069
Most of these are just `#![allow]`ed, because they are things like using
l vs r to differentiate left vs right. These would be made less clear by
taking the advice of `similar_names`
Boxes are a bit magic in that they need to use `*` to get an owned value
out of the box. They implement `Deref` but that only returns a
reference. This means an easy way to convert an `Option<Box<T>>` to an
`<Option<T>` is:
```
box_option.map(|b| *b)
```
However, since b36bb0a6 the `map_clone` lint is detecting this as an
attempt to copy the box. Fix by excluding boxes completely from the
deref part of this lint.
Fixes#3274
Handles cases of `.collect().len()`, `.collect().is_empty()`, and
`.collect().contains()`. This lint is intended to be generic enough to
be added to at a later time with other similar patterns that could be
optimized.
Closes#3034
Make explicit_iter_loop and explicit_into_iter_loop allow-by-default, so
that people can turn them on if they want to enforce that style; avoid
presenting them as *the* idiomatic Rust style, rather than just *a* style.
This includes the type name, so is clear, and may be necessary.
There doesn't seem to be an obviously cleaner way to pull out the
literal text of the named type here.
Fixes#2879
Recategorize `range_plus_one` and `range_minus_one` to `complexity`.
This moves `range_plus_one` out of the nursery as the inclusive range
syntax is now stable. Both are moved to `complexity` as it is more
consistent with other lints such as `int_plus_one`.
The docs claim that `String::push_str` is better than `String::add` because `String::add` allocates a new string and drops the old one, but this is not true. In fact, `add` reuses the existing string and grows it only if its capacity is exceeded, exactly like `push_str`. Their performance is identical since `add` is just a wrapper for `push_str`:
```
fn add(mut self, other: &str) -> String {
self.push_str(other);
self
}
```
35bf1ae257/src/liballoc/string.rs (L1922-L1925)
Warning was:
warning: the feature `macro_vis_matcher` has been stable since 1.29.0 and no longer requires an attribute to enable
--> src/lib.rs:4:12
|
4 | #![feature(macro_vis_matcher)]
| ^^^^^^^^^^^^^^^^^
|
= note: #[warn(stable_features)] on by default
This is a follow-up to #2951 that extends the logic to allow for
returning references inside structs/enums/unions. This was a simple
oversight in the first version and it's surprisingly easy to handle.
The `needless_borrow` lint is temporarily disabled because of some false
positives it causes in combination with the `derive` macro.
However the documentation does not explain these issues, but instead
lists `Known problems: None`. To make it clear why this lint is
currently not enabled, a description of the false positives caused by
this lint has been added to the `Known problems` section.
Currently this code will trigger `trivally_copy_pass_by_ref`:
```
struct OuterStruct {
field: [u8; 8],
}
fn return_inner(outer: &OuterStruct) -> &[u8] {
&outer.field
}
```
If we change the `outer` to be pass-by-value it will not live long
enough for us to return the reference. The above example is trivial but
I've hit this in real code that either returns a reference to either the
argument or in to `self`.
This suppresses the `trivally_copy_pass_by_ref` lint if we return a
reference and it has the same lifetime as the argument. This will likely
miss complex cases with multiple lifetimes bounded by each other but it
should cover the majority of cases with little effort.
The macro always negates the result of the given comparison in its
internal check which automatically triggered the lint. As its an
external macro there was no chance to do anything about it which lead
to a white listing of all external macros to prevent further issues.
This commit removes the logic in this PR that linted out-of-bounds constant `usize` indexing on arrays. That case is already handled by rustc's `const_err` lint. Beyond removing the linting logic, the test file and its associated stderr were updated to verify that const `usize` indexing operations on arrays are no longer handled by this `indexing_slicing` lint.
This commit contains a few changes. In an attempt to clarify which test cases should and should not produce stderr it became clear that some cases were being handled incorrectly. In order to address these test cases, a minor re-factor was made to the linting logic itself.
The re-factor was driven by edge case handling including a need for additional match conditions for `ExprCall` (`&x[0..=4]`) and `ExprBinary` (`x[1 << 3]`). Rather than attempt to account for each potential `Expr*` the code was re-factored into simply "if ranged index" and an "otherwise" conditions.
The changes reflected in this commit (requested in PR #2790) are as follows:
- Extended `INDEXING_SLICING` documentation to include the array type so that it is clearer when indexing operations are allowed.
- Variable `ty` defined identically in multiple scopes was moved to an outer scope so it's only defined once.
- Added a missing return statement to ensure only one lint is triggered by a scenario.
- Prettified match statement with a `let` clause. (I learned something new!)
- Added `&x[5..].iter().map(|x| 2 * x).collect::<Vec<i32>>()` and `&x[2..].iter().map(|x| 2 * x).collect::<Vec<i32>>()` to the test cases. The first _should trigger the lint/stderr_ and the second _should not_.
The changes reflected in this commit are as follows:
- Revised `IndexingSlicingPass` struct name to IndexingSlicing for consistency with the rest of the code base.
- Revised match arm condition to use `(..)` shorthand in favor of `(_, _, _)`.
- Restored a couple telling variable names.
- Calls to `cx.span_lint` were revised to use `utils::span_help_and_lint`.
- Took a stab at refactoring some generalizable calls to `utils::span_help_and_lint` to minimize duplicate code.
- Revised INDEXING_SLICING declaration to pedantic rather than restriction.
- Added `&x[0..].get(..3)` to the test cases.
This commit renames instances of `array_indexing` to `indexing_slicing` and moves the `indexing_slicing` lint to the `clippy_pedantic` group. The justification for this commit's changes are detailed in the previous commit's message.
Hey there clippy team! I've made some assumptions in this PR and I'm not at all certain they'll look like the right approach to you. I'm looking forward to any feedback or revision requests you have, thanks!
Prior to this commit the `indexing_slicing` lint was limited to indexing/slicing operations on arrays. This meant that the scope of a really useful lint didn't include vectors. In order to include vectors in the `indexing_slicing` lint a few steps were taken.
The `array_indexing.rs` source file in `clippy_lints` was renamed to `indexing_slicing.rs` to more accurately reflect the lint's new scope. The `OUT_OF_BOUNDS_INDEXING` lint persists through these changes so if we can know that a constant index or slice on an array is in bounds no lint is triggered.
The `array_indexing` tests in the `tests/ui` directory were also extended and moved to `indexing_slicing.rs` and `indexing_slicing.stderr`.
The `indexing_slicing` lint was moved to the `clippy_pedantic` lint group.
A specific "Consider using" string was added to each of the `indexing_slicing` lint reports.
At least one of the test scenarios might look peculiar and I'll leave it up to y'all to decide if it's palatable. It's the result of indexing the array `x` after `let x = [1, 2, 3, 4];`
```
error: slicing may panic. Consider using `.get(..n)`or `.get_mut(..n)`instead
--> $DIR/indexing_slicing.rs:23:6
|
23 | &x[0..][..3];
| ^^^^^^^^^^^
```
The error string reports only on the second half's range-to, because the range-from is in bounds!
Again, thanks for taking a look.
Closes#2536
This checks for things like
if x.is_some() {
x.unwrap()
}
which should be written using `if let` or `match` instead.
In the process I moved some logic to determine which variables are
mutated in an expression to utils/usage.rs.
- added tests for common usages of format and as_str arguments to expect
- added tests for usages of Option and Result types
- given performance impact of passing non literal expressions to expect, added to perf group
