Address `unnecessary_to_owned` false positive
My proposed fix for #8759 is to revise the conditions that delineate `redundant_clone` and `unnecessary_to_owned`:
```rust
// Only flag cases satisfying at least one of the following three conditions:
// * the referent and receiver types are distinct
// * the referent/receiver type is a copyable array
// * the method is `Cow::into_owned`
// This restriction is to ensure there is no overlap between `redundant_clone` and this
// lint. It also avoids the following false positive:
// https://github.com/rust-lang/rust-clippy/issues/8759
// Arrays are a bit of a corner case. Non-copyable arrays are handled by
// `redundant_clone`, but copyable arrays are not.
```
This change causes a few cases that were previously flagged by `unnecessary_to_owned` to no longer be flagged. But one could argue those cases would be better handled by `redundant_clone`.
Closes#8759
changelog: none
Only crate root def-ids don't have a parent, and in majority of cases the argument of `DefIdTree::parent` cannot be a crate root.
So we now panic by default in `parent` and introduce a new non-panicing function `opt_parent` for cases where the argument can be a crate root.
Same applies to `local_parent`/`opt_local_parent`.
This adds test to make sure correct behavior of lint
- The first test's option variable is not a temporary variable
- The second test does not make usage of `take()`
- The third test makes usage of `take()` and uses a temporary variable
Instead of type checking the entire expression (causing a false
positive), only type check for a subset of the expression (the receiver of
the matched function: `take()`)
This lint checks if Option::take() is used on a temporary value (a value
that is not of type &mut Option and that is not a Place expression) to
suggest omitting take()
fix unnecessary_to_owned about msrv
This PR fixes ``[`unnecessary_owned`]``.
## What
```rust
# sample code
fn _msrv_1_35() {
#![clippy::msrv = "1.35"]
let _ = &["x"][..].to_vec().into_iter();
}
fn _msrv_1_36() {
#![clippy::msrv = "1.36"]
let _ = &["x"][..].to_vec().into_iter();
}
```
If we will check this code using clippy, ``[`unnecessary_owned`]`` will modify the code as follows.
```rust
error: unnecessary use of `to_vec`
--> $DIR/unnecessary_to_owned.rs:219:14
|
LL | let _ = &["x"][..].to_vec().into_iter();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use: `["x"][..].iter().copied()`
error: unnecessary use of `to_vec`
--> $DIR/unnecessary_to_owned.rs:224:14
|
LL | let _ = &["x"][..].to_vec().into_iter();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use: `["x"][..].iter().copied()`
```
This is incorrect. Because `Iterator::copied` was estabilished in 1.36.
## Why
This bug was caused by not separating "copied" and "clone" by reference to msrv.
89ee6aa6e3/clippy_lints/src/methods/unnecessary_to_owned.rs (L195)
So, I added a conditional branch and described the corresponding test.
Thank you in advance.
changelog: fix wrong suggestions about msrv in [`unnecessary_to_owned`]
r! `@giraffate`
New lint `is_digit_ascii_radix`
Closes#6399
changelog: Added [`is_digit_ascii_radix`]: recommend `is_ascii_digit()` or `is_ascii_hexdigit()` in place of `is_digit(10)` and `is_digit(16)`
Remove overlap between `manual_split_once` and `needless_splitn`
changelog: Remove overlap between [`manual_split_once`] and [`needless_splitn`]. Fixes some incorrect `rsplitn` suggestions for [`manual_split_once`]
Things that can trigger `needless_splitn` no longer trigger `manual_split_once`, e.g.
```rust
s.[r]splitn(2, '=').next();
s.[r]splitn(2, '=').nth(0);
s.[r]splitn(3, '=').next_tuple();
```
Fixes some suggestions:
```rust
let s = "should not match";
s.rsplitn(2, '.').nth(1);
// old -> Some("should not match")
Some(s.rsplit_once('.').map_or(s, |x| x.0));
// new -> None
s.rsplit_once('.').map(|x| x.0);
s.rsplitn(2, '.').nth(1)?;
// old -> "should not match"
s.rsplit_once('.').map_or(s, |x| x.0);
// new -> early returns
s.rsplit_once('.')?.0;
```
Remember mutability in `DefKind::Static`.
This allows to compute the `BodyOwnerKind` from `DefKind` only, and
removes a direct dependency of some MIR queries onto HIR.
As a side effect, it also simplifies metadata, since we don't need 4
flavours of `EntryKind::*Static` any more.
This allows to compute the `BodyOwnerKind` from `DefKind` only, and
removes a direct dependency of some MIR queries onto HIR.
As a side effect, it also simplifies metadata, since we don't need 4
flavours of `EntryKind::*Static` any more.
