Add `unused_format_specs` lint
Currently catches two cases:
An empty precision specifier:
```rust
// the same as {}
println!("{:.}", x);
```
And using formatting specs on `format_args!()`:
```rust
// prints `x.`, not `x .`
println("{:5}.", format_args!("x"));
```
changelog: new lint: [`unused_format_specs`]
[`unnecessary_cast`] Do not lint negative hexadecimal literals when cast as floats
fix https://github.com/rust-lang/rust-clippy/issues/9603
changelog: [`unnecessary_cast`] Do not lint negative hexadecimal literals when cast as floats
[`zero_prefixed_literal`] Do not advise to use octal form if not possible
fix https://github.com/rust-lang/rust-clippy/issues/9651
changelog: [`zero_prefixed_literal`] Do not advise to use octal form if not possible
Add new lint `partial_pub_fields`
Signed-off-by: TennyZhuang <zty0826@gmail.com>
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: `partial_pub_fields`: new lint to disallow partial fields of a struct be pub
Resolve#9604
Expand internal lint `unnecessary_def_path`
This PR does essentially two things:
* Separates the internal lints into modules by pass. (`internal_lints.rs` was over 1400 lines, which is a little unruly IMHO.)
* ~Adds a new~ Expands the `unnecessary_def_path` internal lint to flag hardcoded paths to diagnostic and language items.
My understanding is that the latter is currently done by reviewers. Automating this process should make things easier for both reviewers and contributors.
I could make the first bullet a separate PR, or remove it entirely, if desired.
changelog: Add internal lint `diagnostic_item_path`
Add a suggestion and a note about orphan rules for `from_over_into`
Adds a machine applicable suggestion to convert the `Into` impl into a `From` one to `from_over_into`
Also adds a note explaining that `impl From<Local> for Foreign` is fine if the `Into` type is foreign
Closes#7444
Addresses half of #9638
changelog: [`from_over_into`] Add a suggestion and a note about orphan rules
Fix edition revision ui tests
#9605 had me wondering how the edition revision tests were working for `manual_assert` but not for `@nyurik,` but it turns out `manual_assert`'s tests weren't working either. I checked how `rust-lang/rust` does it and apparently it comes down to whitespace, `//[rev] edition:X` works 😬
Removes the revisions from `match_wild_err_arm` as I couldn't find any edition dependant behaviour there
r? `@llogiq`
changelog: none
add tests in `implicit_saturating_sub` lint
This adds more tests to the `implicit_saturating_sub` lint to rule out certain false positives that have appeared in the past.
Now with those false positives out of the equation, we can move the lint to `style`.
---
changelog: promote [`implicit-saturating-sub`] to the `style` category
Fix to_string_in_format_args in parens
Fix suggestions like
```
print!("error: something failed at {}", (Location::caller().to_string()));
```
where the parenthesis enclose some portion of the value.
Fixes#9540
changelog: [`to_string_in_format_args`]: fix incorrect fix when value is enclosed in parenthesis
Fix suggestions like
```
print!("error: something failed at {}", (Location::caller().to_string()));
```
where the parenthesis enclose some portion of the value.
Don't suggest moving tuple structs with a significant drop to late evaluation
fixes#9608
changelog: Don't suggest moving tuple structs with a significant drop to late evaluation
Uplift `clippy::for_loops_over_fallibles` lint into rustc
This PR, as the title suggests, uplifts [`clippy::for_loops_over_fallibles`] lint into rustc. This lint warns for code like this:
```rust
for _ in Some(1) {}
for _ in Ok::<_, ()>(1) {}
```
i.e. directly iterating over `Option` and `Result` using `for` loop.
There are a number of suggestions that this PR adds (on top of what clippy suggested):
1. If the argument (? is there a better name for that expression) of a `for` loop is a `.next()` call, then we can suggest removing it (or rather replacing with `.by_ref()` to allow iterator being used later)
```rust
for _ in iter.next() {}
// turns into
for _ in iter.by_ref() {}
```
2. (otherwise) We can suggest using `while let`, this is useful for non-iterator, iterator-like things like [async] channels
```rust
for _ in rx.recv() {}
// turns into
while let Some(_) = rx.recv() {}
```
3. If the argument type is `Result<impl IntoIterator, _>` and the body has a `Result<_, _>` type, we can suggest using `?`
```rust
for _ in f() {}
// turns into
for _ in f()? {}
```
4. To preserve the original behavior and clear intent, we can suggest using `if let`
```rust
for _ in f() {}
// turns into
if let Some(_) = f() {}
```
(P.S. `Some` and `Ok` are interchangeable depending on the type)
I still feel that the lint wording/look is somewhat off, so I'll be happy to hear suggestions (on how to improve suggestions :D)!
Resolves#99272
[`clippy::for_loops_over_fallibles`]: https://rust-lang.github.io/rust-clippy/master/index.html#for_loops_over_fallibles
Further enhance `needless_borrow`, mildly refactor `redundant_clone`
This PR does the following:
* Moves some code from `redundant_clone` into a new `clippy_utils` module called `mir`, and wraps that code in a function called `dropped_without_further_use`.
* Relaxes the "is copyable" condition condition from #9136 by also suggesting to remove borrows from values dropped without further use. The changes involve the just mentioned function.
* Separates `redundant_clone` into modules.
Strictly speaking, the last bullet is independent of the others. `redundant_clone` is somewhat hairy, IMO. Separating it into modules makes it slightly less so, by helping to delineate what depends upon what.
I've tried to break everything up into digestible commits.
r? `@Jarcho`
(`@Jarcho` I hope you don't mind.)
changelog: continuation of #9136
Add `manual_filter` lint for `Option`
Share much of its implementation with `manual_map` and should greatly benefit from its previous feedback.
I'm sure it's possible to even more refactor both and would gladly take input on that as well as any clippy idiomatic usage, since this is my first lint addition.
I've added the lint to the complexity section for now, I don't know if every new lint needs to go in nursery first.
The matching could be expanded to more than `Some(<value>)` to lint on arbitrary struct matching inside the `Some` but I've left it like it was for `manual_map` for now. `needless_match::pat_same_as_expr` provides a more generic match example.
close https://github.com/rust-lang/rust-clippy/issues/8822
changelog: Add lint [`manual_filter`] for `Option`
extend `box-default` lint, add suggestion
This extends the recently added `box-default` lint to also cover `Box::new(vec![])`, `Box::new(String::from(""))` and `Box::new(Vec::from([]))`. Also the lint now suggests a suitable replacement. I did not find a simple way to check whether the type is fully determined by the outside, so I at least checked for some variations to remove the turbofish in those cases.
---
changelog: none
lint::unsafe_removed_from_name: fix false positive result when allowed
changelog: [`unsafe_removed_from_name`] Fix allowing on imports produces a false positive on `useless_attribute`.
Fixes: #9197
Signed-off-by: Andy-Python-Programmer <andypythonappdeveloper@gmail.com>
FormatArgsExpn: Find comma spans and ignore weird proc macro spans
Fixes the following cases:
A missing `, 1` from the `expect_fun_call` suggestion:
```rust
Some(()).expect(&format!("{x} {}", 1));
```
```
warning: use of `expect` followed by a function call
--> t.rs:7:14
|
7 | Some(()).expect(&format!("{x} {}", 1));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|| panic!("{x} {}"))`
```
The suggestion removing from the comma in the comment rather than the one after the format string:
```rust
println!(
"{}",
// a comment, with a comma in it
x
);
```
```
warning: variables can be used directly in the `format!` string
--> t.rs:9:5
|
9 | / println!(
10 | | "{}",
11 | | // a comment, with a comma in it
12 | | x
13 | | );
| |_____^
|
help: change this to
|
10 ~ "{x}",
11 ~ // a comment
|
```
It also no longer accepts expansions where a format string or argument has a "weird" proc macro span, that is one where the literal/expression it outputs has the span of one of its inputs. Kind of like a `format_args` specific `clippy_utils::is_from_proc_macro`, e.g. `format!(indoc! {" ... "})`
changelog: [`expect_fun_call`]: Fix suggestion for `format!` using captured variables
changelog: [`print_literal`], [`write_literal`], [`uninlined_format_args`]: Fix suggestion when following a comment including a comma
[arithmetic-side-effects] Do not ignore literal references
To my utter surprise, `rustc` does does not warn stuff like `let n: u8 = &255 + &1` or `let n: u8 = 255 + &1`.
changelog: [arithmetic-side-effects] Do not ignore literal references
fallout: fix tests to allow uninlined_format_args
In order to switch `clippy::uninlined_format_args` from pedantic to style, all existing tests must not raise a warning. I did not want to change the actual tests, so this is a relatively minor change that:
* add `#![allow(clippy::uninlined_format_args)]` where needed
* normalizes all allow/deny/warn attributes
* all allow attributes are grouped together
* sorted alphabetically
* the `clippy::*` attributes are listed separate from the other ones.
* deny and warn attributes are listed before the allowed ones
See also https://github.com/rust-lang/rust-clippy/pull/9233, https://github.com/rust-lang/rust-clippy/pull/9525, https://github.com/rust-lang/rust-clippy/pull/9527
cc: `@llogiq` `@Alexendoo`
changelog: none
Fix and improve `match_type_on_diagnostic_item`
This extracts the fix for the lint out of #7647. There's still a couple of other functions to check, but at least this will get lint working again.
The two added util functions (`is_diagnostic_item` and `is_lang_item`) are needed to handle `DefId` for unit and tuple struct/variant constructors. The `rustc_diagnostic_item` and `lang` attributes are attached to the struct/variant `DefId`, but most of the time they are used through their constructors which have a different `DefId`. The two utility functions will check if the `DefId` is for a constructor and switch to the associated struct/variant `DefId`.
There does seem to be a bug on rustc's side where constructor `DefId`s from external crates seem to be returning `DefKind::Variant` instead of `DefKind::Ctor()`. There's a workaround put in right.
changelog: None
In order to switch `clippy::uninlined_format_args` from pedantic to
style, all existing tests must not raise a warning. I did not want to
change the actual tests, so this is a relatively minor change that:
* add `#![allow(clippy::uninlined_format_args)]` where needed
* normalizes all allow/deny/warn attributes
* all allow attributes are grouped together
* sorted alphabetically
* the `clippy::*` attributes are listed separate from the other ones.
* deny and warn attributes are listed before the allowed ones
changelog: none
Remove unused `.fixed` files, only run asm_syntax doctests on x86
Two small changes, removes some unused `.fixed` and makes `clippy_lints` doctests pass on non x86 arches
changelog: none
* Check for `const`s and `static`s from external crates
* Check for `LangItem`s
* Handle inherent functions which have the same name as a field
* Also check the following functions:
* `match_trait_method`
* `match_def_path`
* `is_expr_path_def_path`
* `is_qpath_def_path`
* Handle checking for a constructor to a diagnostic item or `LangItem`
let unnecessary_cast work for trivial non_literal expressions
Signed-off-by: TennyZhuang <zty0826@gmail.com>
---
changelog: [`unnecessary_cast`]: fix for trivial non_literal expressions
Fixes#9562
[`unnecessary_cast`] add parenthesis when negative number uses a method
fix#9563
The issue was probably introduced by 90fe3bea52
changelog: [`unnecessary_cast`] add parenthesis when negative number uses a method
r? llogiq
Implement `manual_clamp` lint
Fixes#9477Fixes#6751
Identifies common patterns where usage of the `clamp` function would be more succinct and clear, and suggests using the `clamp` function instead.
changelog: [`manual_clamp`]: Implement manual_clamp lint
This lint detects calls to a `&self`-taking `as_ptr` method, where
the result is then immediately cast to a `*mut T`. Code like this
is probably invalid, as that pointer will not have write permissions,
and `*mut T` is usually used to write through.
fix [`needless_borrow`], [`explicit_auto_deref`] FPs on unions
fix https://github.com/rust-lang/rust-clippy/issues/9383
changelog: fix [`needless_borrow`] false positive on unions
changelog: fix [`explicit_auto_deref`] false positive on unions
Left a couple debug derived impls on purpose I needed to debug as I don't think it's noise
Don't lint unstable moves in `std_instead_of_core`
Fixes#9515
changelog: [`std_instead_of_core`]: No longer suggests unstable modules such as `core::error`
add `box-default` lint
This adds a `box-default` lint to suggest using `Box::default()` instead of `Box::new(Default::default())`, which offers less moving parts and potentially better performance according to [the perf book](https://nnethercote.github.io/perf-book/standard-library-types.html#box).
---
changelog: add [`box_default`] lint
[`needless_return`] Recursively remove unneeded semicolons
fix#8336,
fix#8156,
fix https://github.com/rust-lang/rust-clippy/issues/7358,
fix#9192,
fix https://github.com/rust-lang/rust-clippy/issues/9503
changelog: [`needless_return`] Recursively remove unneeded semicolons
For now the suggestion about removing the semicolons are hidden because they would be very noisy and should be obvious if the user wants to apply the lint manually instead of using `--fix`. This could be an issue for beginner, but haven't found better way to display it.
[arithmetic-side-effects] Consider references
Takes into consideration integer references like `&i32::MAX` because currently things like `let _ = &1 + 0` trigger the lint.
changelog: FP: [`arithmetic_side_effects`]: Now ignores references
[9507](https://github.com/rust-lang/rust-clippy/pull/9507)
Don't lint `*_interior_mutable_const` on unions due to potential ICE.
fixes#9445
cc rust-lang/rust#101113
This started ICE'ing sometime last month due to stricter UB checks. I'm not sure how we could check the value of a union as MIRI doesn't seem to store which field is currently active.
changelog: Don't ICE on const unions containing a `!Freeze` type.
Silence [`question_mark`] in const context
fix https://github.com/rust-lang/rust-clippy/issues/9175
When `const_try` is stabilised can be turned into a MSRV
changelog: Silence [`question_mark`] in const context
Stabilize const `BTree{Map,Set}::new`
The FCP was completed in #71835.
Since `len` and `is_empty` are not const stable yet, this also creates a new feature for them since they previously used the same `const_btree_new` feature.
Implement https://github.com/rust-lang/rust-clippy/issues/8368 - a new
lint to inline format arguments such as `print!("{}", var)` into
`print!("{var}")`.
code | suggestion | comment
---|---|---
`print!("{}", var)` | `print!("{var}")` | simple variables
`print!("{0}", var)` | `print!("{var}")` | positional variables
`print!("{v}", v=var)` | `print!("{var}")` | named variables
`print!("{0} {0}", var)` | `print!("{var} {var}")` | aliased variables
`print!("{0:1$}", var, width)` | `print!("{var:width$}")` | width
support
`print!("{0:.1$}", var, prec)` | `print!("{var:.prec$}")` | precision
support
`print!("{:.*}", prec, var)` | `print!("{var:.prec$}")` | asterisk
support
code | suggestion | comment
---|---|---
`print!("{0}={1}", var, 1+2)` | `print!("{var}={0}", 1+2)` | Format
string uses an indexed argument that cannot be inlined. Supporting this
case requires re-indexing of the format string.
changelog: [`uninlined_format_args`]: A new lint to inline format
arguments, i.e. `print!("{}", var)` into `print!("{var}")`
Since `len` and `is_empty` are not const stable yet, this also
creates a new feature for them since they previously used the same
`const_btree_new` feature.
[`never_loop`]: Fix FP with let..else statements.
Fixes#9356
This has been bugging me for a while, so I thought I'd take a stab at it! I'm completely uncertain about the quality of my code, but I think it's an alright start, so opening this PR to get some feedback from more experienced clippy people :)
changelog: [`never_loop`]: Fix FP with let..else statements
Fixes#9504
Compiler generated call `into_iter` nodes return empty substs
which we need when checking it's predicates. Handle this by
simply exitting when we encounter one. This change introduces
false negatives in place of the ICEs.
[arithmetic-side-effects] Finish non-overflowing ops
Extends https://github.com/rust-lang/rust-clippy/pull/9474 to also take into consideration "raw" binary operations. For example, `let a = b / 2` and `let a = 1 * b` won't trigger the lint.
changelog: [arithmetic-side-effects] Finish non-overflowing ops
Make module-style lints resilient to --remap-path-prefix
changelog: [`self_named_module_files`], [`mod_module_files`]: Make module-style lints resilient to `--remap-path-prefix`
Without this if a user has configured `--remap-path-prefix` to be used for a prefix containing the current source directory the lints would silently fail to generate a warning.
Migrate write.rs to a late pass
changelog: Migrates write.rs from a pre expansion pass to a late pass
changelog: [`positional_named_format_parameters`] is renamed in favour of the rustc lint `named_arguments_used_positionally`
- Macros are now identified by diagnostic items, so will no longer lint user defined macros named, e.g. a custom `print!`
- `print_literal`/`write_literal` no longer lint no longer lint literals that come from macro expansions, e.g. `env!("FOO")`
- `print_with_newline`/`write_with_newline` no longer lint strings with any internal `\r` or `\n`s
~~A false negative, `print_literal`/`write_literal` don't lint format strings that produce `FormatSpec`s, e.g. ones containing pretty print/width/align specifiers~~
Suggestion changes:
- ~~`print_literal`/`write_literal` no longer have suggestions, as the spans for the `{}`s were not easily obtainable~~
- `print_with_newline`/`write_with_newline` has a better suggestion for a sole literal newline, but no longer has suggestions for len > 1 strings that end in a literal newline
- ~~`use_debug` spans are less precise, now point to the whole format string~~
The diff for write.rs is pretty unwieldy, other than for the `declare_clippy_lint!`s I think you'd be better off viewing it as a brand new file rather than looking at the diff, as it's mostly written from scratch
cc #6610, fixes#5721, fixes#7195, fixes#8615
Fix `unused_peekable` closure and `f(&mut peekable)` false positives
changelog: Fix [`unused_peekable`] false positive when peeked in a closure or called as `f(&mut peekable)`
The `return`/`break` changes aren't part of the fix, they allow an earlier return in some cases. `break` is replaced with `return` for style purposes as they do the same thing in this case
Fixes#9456Fixes#9462
