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`.
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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`
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*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
Ensure `Copy` exception in trait definition for `wrong_self_conventio…
Add a test case to ensure `Copy` exception is preserved also in trait definition, when passing `self` by value.
Follow up of #6316
changelog: none
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
make MIR graphviz generation use gsgdt
gsgdt [https://crates.io/crates/gsgdt] is a crate which provides an
interface for stringly typed graphs. It also provides generation of
graphviz dot format from said graph.
This is the first in a series of PRs on moving graphviz code out of rustc into normal crates and then implementating graph diffing on top of these crates.
r? `@oli-obk`
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 🙃.
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Fixes#5552
changelog: Fixed a false positive in the `match_single_binding` lint with `#[cfg()]` macro
