changelog: [`manual_ok_err`]: new lint
Detect manual implementations of `.ok()` or `.err()`, as in
```rust
let a = match func() {
Ok(v) => Some(v),
Err(_) => None,
};
let b = if let Err(v) = func() {
Some(v)
} else {
None
};
```
which can be replaced by
```rust
let a = func().ok();
let b = func().err();
```
This pattern was detected in the wild in the Rust reimplementation of
coreutils:
https://github.com/uutils/coreutils/pull/6886#pullrequestreview-2465160137
Fixes#13375
I've added the lint next to the other attribute-related ones. Not sure
if this is the correct place, since while we are looking after the
`packed`-attribute (there is nothing we can do about types defined
elsewhere), we are more concerned about the type's representation set by
the attribute (instead of "duplicate attributes" and such).
The lint simply looks at the attributes themselves without concern for
the item-kind, since items where `repr` is not allowed end up in a
compile-error anyway.
I'm somewhat concerned about the level of noise this lint would cause
if/when it goes into stable, although it does _not_ come up in
`lintcheck`.
```
changelog: [`repr_packed_without_abi`]: Initial implementation
```
https://github.com/rust-lang/rust/issues/133150
This is more likely to be intended as an intra-doc link than it is to be
intended as a refdef. If a refdef is intended, it does not need to be
nested within a list item.
```markdown
- [`LONG_INTRA_DOC_LINK`]: this
looks like an intra-doc link,
but is actually a refdef.
The first line will seem to
disappear when rendered as HTML.
```
> - [`LONG_INTRA_DOC_LINK`]: this
> looks like an intra-doc link,
> but is actually a refdef.
> The first line will seem to
> disappear when rendered as HTML.
changelog: [`doc_nested_refdefs`]: add suspicious lint for link def at
start of list items and block quotes
This is more likely to be intended as an intra-doc link than it is
to be intended as a refdef. If a refdef is intended, it does not
need to be nested within a list item or quote.
```markdown
- [`LONG_INTRA_DOC_LINK`]: this
looks like an intra-doc link,
but is actually a refdef.
The first line will seem to
disappear when rendered as HTML.
```
It's becoming more and more common to see people including markdown
files in their code using `doc = include_str!("...")`, which is great.
However, often there is no condition on this include, which is not great
because it slows down compilation and might trigger recompilation if
these files are updated.
This lint aims at fixing this situation.
changelog: Add new lint `doc_include_without_cfg`
This lint checks for code that looks like
```rust
let something : Vec<_> = (0..100).map(|_| {
1 + 2 + 3
}).collect();
```
which is more clear as
```rust
let something : Vec<_> = std::iter::repeat_with(|| {
1 + 2 + 3
}).take(100).collect();
```
or
```rust
let something : Vec<_> =
std::iter::repeat_n(1 + 2 + 3, 100)
.collect();
```
That is, a map over a range which does nothing with the parameter
passed to it is simply a function (or closure) being called `n`
times and could be more semantically expressed using `take`.
Implement lint for regex::Regex compilation inside a loop
Closes#598.
Seems like a pretty simple one, I'm not sure if I sorted out all the lint plumbing correctly because I was adding it to the existing regex pass, but seems to work. The name is a bit jank and I'm super open to suggestions for changing it.
changelog: [`regex_creation_in_loops`]: Added lint for Regex compilation inside loops.
Extend `implicit_saturating_sub` lint
Fixes#10070.
It can serve as base if we want to add equivalent checks for other arithmetic operations.
Also one important note: when writing this lint, I realized that I could check for wrong conditions performed beforehand on subtraction and added another part in the lint. Considering they both rely on the same checks, I kept both in the same place. Not sure if it makes sense though...
changelog: Extend `implicit_saturating_sub` lint
Add new lint: `used_underscore_items`
Closes#13260
---
changelog: new [`used_underscore_items`] lint against using items with a single leading underscore
