rust-clippy/tests/ui/wrong_self_convention.rs
Nick Mathewson 3d41358a55 wrong_self_convention: Match SelfKind::No more restrictively
The `wrong_self_convention` lint uses a `SelfKind` type to decide
whether a method has the right kind of "self" for its name, or whether
the kind of "self" it has makes its name confusable for a method in
a common trait.  One possibility is `SelfKind::No`, which is supposed
to mean "No `self`".

Previously, SelfKind::No matched everything _except_ Self, including
references to Self.  This patch changes it to match Self, &Self, &mut
Self, Box<Self>, and so on.

For example, this kind of method was allowed before:

```
impl S {
    // Should trigger the lint, because
    // "methods called `is_*` usually take `self` by reference or no `self`"
    fn is_foo(&mut self) -> bool { todo!() }
}
```

But since SelfKind::No matched "&mut self", no lint was triggered
(see #8142).

With this patch, the code above now gives a lint as expected.

Fixes #8142

changelog: [`wrong_self_convention`] rejects `self` references in more cases
2021-12-31 23:39:40 -05:00

211 lines
4.6 KiB
Rust

#![warn(clippy::wrong_self_convention)]
#![allow(dead_code)]
fn main() {}
#[derive(Clone, Copy)]
struct Foo;
impl Foo {
fn as_i32(self) {}
fn as_u32(&self) {}
fn into_i32(self) {}
fn is_i32(self) {}
fn is_u32(&self) {}
fn to_i32(self) {}
fn from_i32(self) {}
pub fn as_i64(self) {}
pub fn into_i64(self) {}
pub fn is_i64(self) {}
pub fn to_i64(self) {}
pub fn from_i64(self) {}
// check whether the lint can be allowed at the function level
#[allow(clippy::wrong_self_convention)]
pub fn from_cake(self) {}
fn as_x<F: AsRef<Self>>(_: F) {}
fn as_y<F: AsRef<Foo>>(_: F) {}
}
struct Bar;
impl Bar {
fn as_i32(self) {}
fn as_u32(&self) {}
fn into_i32(&self) {}
fn into_u32(self) {}
fn is_i32(self) {}
fn is_u32(&self) {}
fn to_i32(self) {}
fn to_u32(&self) {}
fn from_i32(self) {}
pub fn as_i64(self) {}
pub fn into_i64(&self) {}
pub fn is_i64(self) {}
pub fn to_i64(self) {}
pub fn from_i64(self) {}
// test for false positives
fn as_(self) {}
fn into_(&self) {}
fn is_(self) {}
fn to_(self) {}
fn from_(self) {}
fn to_mut(&mut self) {}
}
// Allow Box<Self>, Rc<Self>, Arc<Self> for methods that take conventionally take Self by value
#[allow(clippy::boxed_local)]
mod issue4293 {
use std::rc::Rc;
use std::sync::Arc;
struct T;
impl T {
fn into_s1(self: Box<Self>) {}
fn into_s2(self: Rc<Self>) {}
fn into_s3(self: Arc<Self>) {}
fn into_t1(self: Box<T>) {}
fn into_t2(self: Rc<T>) {}
fn into_t3(self: Arc<T>) {}
}
}
// False positive for async (see #4037)
mod issue4037 {
pub struct Foo;
pub struct Bar;
impl Foo {
pub async fn into_bar(self) -> Bar {
Bar
}
}
}
// Lint also in trait definition (see #6307)
mod issue6307 {
trait T: Sized {
fn as_i32(self) {}
fn as_u32(&self) {}
fn into_i32(self) {}
fn into_i32_ref(&self) {}
fn into_u32(self) {}
fn is_i32(self) {}
fn is_u32(&self) {}
fn to_i32(self) {}
fn to_u32(&self) {}
fn from_i32(self) {}
// check whether the lint can be allowed at the function level
#[allow(clippy::wrong_self_convention)]
fn from_cake(self) {}
// test for false positives
fn as_(self) {}
fn into_(&self) {}
fn is_(self) {}
fn to_(self) {}
fn from_(self) {}
fn to_mut(&mut self) {}
}
trait U {
fn as_i32(self);
fn as_u32(&self);
fn into_i32(self);
fn into_i32_ref(&self);
fn into_u32(self);
fn is_i32(self);
fn is_u32(&self);
fn to_i32(self);
fn to_u32(&self);
fn from_i32(self);
// check whether the lint can be allowed at the function level
#[allow(clippy::wrong_self_convention)]
fn from_cake(self);
// test for false positives
fn as_(self);
fn into_(&self);
fn is_(self);
fn to_(self);
fn from_(self);
fn to_mut(&mut self);
}
trait C: Copy {
fn as_i32(self);
fn as_u32(&self);
fn into_i32(self);
fn into_i32_ref(&self);
fn into_u32(self);
fn is_i32(self);
fn is_u32(&self);
fn to_i32(self);
fn to_u32(&self);
fn from_i32(self);
// check whether the lint can be allowed at the function level
#[allow(clippy::wrong_self_convention)]
fn from_cake(self);
// test for false positives
fn as_(self);
fn into_(&self);
fn is_(self);
fn to_(self);
fn from_(self);
fn to_mut(&mut self);
}
}
mod issue6727 {
#[derive(Clone, Copy)]
struct FooCopy;
impl FooCopy {
fn to_u64(self) -> u64 {
1
}
// trigger lint
fn to_u64_v2(&self) -> u64 {
1
}
}
struct FooNoCopy;
impl FooNoCopy {
// trigger lint
fn to_u64(self) -> u64 {
2
}
fn to_u64_v2(&self) -> u64 {
2
}
}
}
pub mod issue8142 {
struct S;
impl S {
// Should lint: is_ methods should only take &self, or no self at all.
fn is_still_buggy(&mut self) -> bool {
false
}
// Should not lint: "no self at all" is allowed.
fn is_forty_two(x: u32) -> bool {
x == 42
}
// Should not lint: &self is allowed.
fn is_test_code(&self) -> bool {
true
}
}
}