Rework diagnostics for wrong number of generic args (fixes#66228 and #71924)
This PR reworks the `wrong number of {} arguments` message, so that it provides more details and contextual hints.
This makes it possible to pass the `Impl` directly to functions, instead
of having to pass each of the many fields one at a time. It also
simplifies matches in many cases.
Catch `pointer::cast` too in `cast_ptr_alignment`
Fixes#4708
Although there were some discussion in the issue, this PR implements the original feature. I think `cast_ptr_alignment` should exist as it is, separated from `ptr_as_ptr`.
---
changelog: Extend `cast_ptr_alignment` lint for the `pointer::cast` method
Fix FP for `boxed_local` lint in default trait fn impl
Fix FP on default trait function implementation on `boxed_local` lint.
Maybe I checked too much when looking if `self` is carrying `Self` in its bound type.
I can't find a good test case for this, so it could be too much conservative.
Let me know if you think only detecting `self` parameter is enough.
Fixes: #4804
changelog: none
Fix derive and macro related false positives in `field_reassign_with_default`
Closes#6545
changelog: Fix derive and macro related false positives in [`field_reassign_with_default`]
Add a new lint `ptr_as_ptr`
This PR adds a new lint `ptr_as_ptr` which checks for `as` casts between raw pointers without changing its mutability and suggest replacing it with `pointer::cast`. Closes#5890.
Open question: should this lint be `pedantic` or `style`? I set it `pedantic` for now because the original post suggests using it, but I think the lint also fits well to `style`.
---
changelog: New lint `ptr_as_ptr`
Fix: Empty enum never type suggested only if the feature is enabled
This PR addresses [Issue 6422](https://github.com/rust-lang/rust-clippy/issues/6422). Instead of always recommending `never type` for empty enums, Clippy would only recommend [the lint](https://rust-lang.github.io/rust-clippy/master/index.html#empty_enum) if [LatePass.TyCtxt](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/context/struct.TyCtxt.html) has `features().never_type` enabled.
- \[ ] 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`
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: Only trigger [`empty_enum`] lint if `never_type` feature is enabled.
New lint: vec_init_then_push
fixes: #1483
This will trigger on `new`, `default`, and `with_capacity` when the given capacity is less than or equal to the number of push calls. Is there anything else this should trigger on?
changelog: Added lint: `vec_init_then_push`
This splits up clippy::collapsible_if into collapsible_if for
if x {
if y { }
}
=>
if x && y { }
and collapsible_else_if for
if x {
} else {
if y { }
}
=>
if x {
} else if y {
}
so that we can lint for only the latter but not the first if we desire.
changelog: collapsible_if: split up linting for if x {} else { if y {} } into collapsible_else_if lint
Clippy treated Rust 2021 as Rust 2015, because 2018 was checked with
`==` instead of `>=`. This fixes that, such that 2018-specific things
are also enabled for 2021.
- Adds optional default values to const generic parameters in the AST
and HIR
- Parses these optional default values
- Adds a `const_generics_defaults` feature gate
Reassign default private
changelog: fix field_reassign_with_default false positive
* Fix#6344
* Fix assumption that `field: Default::default()` is the same as `..Default::default()`
* Cleanup some redundant logic
Added from_over_into lint
Closes#6456
Added a lint that searches for implementations of `Into<..>` and suggests to implement `From<..>` instead, as it comes with a default implementation of `Into`. Category: style.
changelog: added `from_over_into` lint
Lint also in trait def for `wrong_self_convention`
Extends `wrong_self_convention` to lint also in trait definition.
By the way, I think the `wrong_pub_self_convention` [example](dd826b4626/clippy_lints/src/methods/mod.rs (L197)) is misleading.
On [playground](https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=32615ab3f6009e7e42cc3754be0ca17f), it fires `wrong_self_convention`, so the example (or the lint maybe?) needs to be reworked.
The difference with `wrong_self_convention` [example](dd826b4626/clippy_lints/src/methods/mod.rs (L172)) is mainly the `pub` keyword on the method `as_str`, but the lint doesn't use the function visibility as condition to choose which lint to fire (in fact it uses the visibility of the impl item).
fixes: #6307
changelog: Lint `wrong_self_convention` lint in trait def also
needless_doctest_main: handle correctly parse errors
Before this change, finding an error when parsing a doctest would make Clippy exit without emitting an error. Now we properly catch a fatal error and ignore it.
Also, if a doctest specifies an edition in the info line, it will be used when parsing it.
changelog: needless_doctest_main: handle correctly parse errors
Fixes#6022
Move binder for dyn to each list item
This essentially changes `ty::Binder<&'tcx List<ExistentialTraitRef>>` to `&'tcx List<ty::Binder<ExistentialTraitRef>>`.
This is a first step in moving the `dyn Trait` representation closer to Chalk, which we've talked about in `@rust-lang/wg-traits.`
r? `@nikomatsakis`
Implement if-let match guards
Implements rust-lang/rfcs#2294 (tracking issue: #51114).
I probably should do a few more things before this can be merged:
- [x] Add tests (added basic tests, more advanced tests could be done in the future?)
- [x] Add lint for exhaustive if-let guard (comparable to normal if-let statements)
- [x] Fix clippy
However since this is a nightly feature maybe it's fine to land this and do those steps in follow-up PRs.
Thanks a lot `@matthewjasper` ❤️ for helping me with lowering to MIR! Would you be interested in reviewing this?
r? `@ghost` for now
Fixing a false positive for the `match_single_binding` lint #5552
This is a fix for a false positive in the `match_single_binding` lint when using `#[cfg()]` on a branch. It is sadly a bit hacky but maybe the best solution as rust removes the other branch from the AST before we can even validate it. This fix looks at the code snippet itself and returns if it includes another thick arrow `=>` besides the one matching arm we found. This can again cause false negatives if someone has the following code:
```rust
match x {
// => <-- Causes a false negative
_ => 1,
}
```
I thought about making the code more complex and maybe validating against other things like the `#[cfg()]` macro but I believe that this is the best solution. This has basically switched the issue from a false positive to a false negative in a very specific case.
I'm happy to make some changes if you have any suggestions 🙃.
---
Fixes#5552
changelog: Fixed a false positive in the `match_single_binding` lint with `#[cfg()]` macro
Add MSRV to more lints specified in #6097
add MSRV to more lints specified in #6097
add instructions for adding msrv in other lints
update tests
- [x] `redundant_field_names` requires Rust 1.17 due to suggest feature stablized in that version.
- [x] `redundant_static_lifetimes` requires Rust 1.17 due to suggest feature stablized in that version.
- [x] `filter_map_next` requires Rust 1.30 due to suggest `Iterator::find_map`.
- [x] `checked_conversions` requires Rust 1.34 due to suggest `TryFrom`.
- [x] `match_like_matches_macro` requires Rust 1.42 due to suggest `matches!`. Addressed in #6201
- [x] `manual_strip` requires Rust 1.45 due to suggest `str::{strip_prefix, strip_suffix}`. Addressed in #6201
- [x] `option_as_ref_deref` requires Rust 1.40 due to suggest `Option::{as_deref, as_deref_mut}`. Addressed in #6201
- [x] `manual_non_exhaustive` requires Rust 1.40 due to suggest `#[non_exhaustive]`. Addressed in #6201
- [x] `manual_range_contains` requires Rust 1.35 due to suggest `Range*::contains`.
- [x] `use_self` requires Rust 1.37 due to suggest `Self::Variant on enum`.
- [x] `mem_replace_with_default` requires Rust 1.40 due to suggest `mem::take`.
- [x] `map_unwrap_or` requires Rust 1.41 due to suggest `Result::{map_or, map_or_else}`.
- [x] `missing_const_for_fn` requires Rust 1.46 due to `match/if/loop in const fn` needs that version.
changelog: Add MSRV config to more lints. ^This is now the complete list, AFAWK
Add lint print_stderr
Resolves#6348
Almost identical to print_stdout, this lint applies to the `eprintln!` and `eprint!` macros rather than `println!` and `print!`.
changelog: Add new lint [`print_stderr`]. [`println_empty_string`] and [`print_with_newline`] now apply to `eprint!()` and `eprintln!()` respectively.
Added a lint-fraction-readability flag to the configuration
This adds an option to disable the `unreadable_literal` lint for floats with a longer fraction. This allows users to write `0.100200300` without getting a warning. Fixes#4176
I have some open questions about this PR:
1. I've named the option `lint-fraction-readability` is this a good name or should I rename it to something else?
2. What should the default configuration value be?
* The current default value is `true` as this was also the previous default.
3. Do I have to document this new option somewhere else or will it be extracted from the code comment?
4. The current fix option will also rewrite the fraction if the integer part violates the `unreadable_literal` lint it would otherwise also trigger the `inconsistent_digit_grouping` lint. Is this also okay?
* `1.100200300` will be unaffected by the fix function
* `100200300.100200300` will be effected and fixed to `100_200_300.100_200_300`
---
The project needed some getting used to but I'm happy with the result. A big thank you to `@flip1995` for giving me some pointers for this implementation and to everyone for the great introduction documentation!
---
changelog: Added the `unreadable-literal-lint-fractions` configuration to disable the `unreadable_literal` lint for fractions
Moved map_err_ignore to restriction and updated help message
This MR moves map_err_ignore lint from `pedantic` to the `restriction` category of lints and updates the help message to give the user an option to ignore the lint by naming the closure variable e.g. `.map_err(|_ignored| ...`
---
changelog: move map_err_ignore to restriction category
Specifically ptr::{sub, wrapping_sub, add, wrapping_add, offset, wrapping_offset} and slice::{from_raw_parts, from_raw_parts_mut}
The lint now also looks for size_of calls through casts (Since offset takes an isize)
Also fix review comments:
- Use const arrays and iterate them for the method/function names
- merge 2 if_chain's into one using a rest pattern
- remove unnecessary unsafe block in test
And make the lint only point to the count expression instead of the entire function call
Add Collapsible match lint
changelog: Add collapsible_match lint
Closes#1252Closes#2521
This lint finds nested `match` or `if let` patterns that can be squashed together. It is designed to be very conservative to only find cases where merging the patterns would most likely reduce cognitive complexity.
Example:
```rust
match result {
Ok(opt) => match opt {
Some(x) => x,
_ => return,
}
_ => return,
}
```
to
```rust
match result {
Ok(Some(x)) => x,
_ => return,
}
```
These criteria must be met for the lint to fire:
* The inner match has exactly 2 branches.
* Both the outer and inner match have a "wild" branch like `_ => ..`. There is a special case for `None => ..` to also be considered "wild-like".
* The contents of the wild branches are identical.
* The binding which "links" the matches is never used elsewhere.
Thanks to the hir, `if let`'s are easily included with this lint since they are desugared into equivalent `match`'es.
I think this would fit into the style category, but I would also understand changing it to pedantic.
