mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Ensure that RETURN_SELF_NOT_MUST_USE is not emitted if the method already has a must_use attribute

Browse Source
This commit is contained in:
Guillaume Gomez 2021-12-18 15:26:16 +01:00
parent e93767b395
commit 4da5520205
2 changed files with 14 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
clippy_lints/src/return_self_not_must_use.rs
View File

@ -5,7 +5,7 @@ use rustc_hir::{Body, FnDecl, HirId, TraitItem, TraitItemKind};
use rustc_lint::{LateContext, LateLintPass, LintContext};
use rustc_middle::lint::in_external_macro;
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::Span;
use rustc_span::{sym, Span};
declare_clippy_lint! {
/// ### What it does
@ -86,6 +86,8 @@ impl<'tcx> LateLintPass<'tcx> for ReturnSelfNotMustUse {
// We are only interested in methods, not in functions or associated functions.
if matches!(kind, FnKind::Method(_, _, _));
if let Some(fn_def) = cx.tcx.hir().opt_local_def_id(hir_id);
// We don't want to emit this lint if the `#[must_use]` attribute is already there.
if !cx.tcx.hir().attrs(hir_id).iter().any(|attr| attr.has_name(sym::must_use));
if let Some(impl_def) = cx.tcx.impl_of_method(fn_def.to_def_id());
// We don't want this method to be te implementation of a trait because the
// `#[must_use]` should be put on the trait definition directly.

17
tests/ui/return_self_not_must_use.rs
View File

@ -5,12 +5,12 @@ pub struct Bar;
pub trait Whatever {
fn what(&self) -> Self;
// There should be no warning here!
// There should be no warning here! (returns a reference)
fn what2(&self) -> &Self;
}
impl Bar {
// There should be no warning here!
// There should be no warning here! (note taking a self argument)
pub fn not_new() -> Self {
Self
}
@ -20,22 +20,27 @@ impl Bar {
pub fn bar(self) -> Self {
self
}
// There should be no warning here!
// There should be no warning here! (private method)
fn foo2(&self) -> Self {
Self
}
// There should be no warning here!
// There should be no warning here! (returns a reference)
pub fn foo3(&self) -> &Self {
self
}
// There should be no warning here! (already a `must_use` attribute)
#[must_use]
pub fn foo4(&self) -> Self {
Self
}
}
impl Whatever for Bar {
// There should be no warning here!
// There should be no warning here! (comes from the trait)
fn what(&self) -> Self {
self.foo2()
}
// There should be no warning here!
// There should be no warning here! (comes from the trait)
fn what2(&self) -> &Self {
self
}