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|
//@aux-build:proc_macros.rs
#![allow(unused)]
#![warn(clippy::unused_trait_names)]
#![feature(decl_macro)]
extern crate proc_macros;
fn main() {}
fn bad() {
use std::any::Any as _;
//~^ unused_trait_names
println!("{:?}", "foo".type_id());
}
fn good() {
use std::any::Any as _;
println!("{:?}", "foo".type_id());
}
fn used_good() {
use std::any::Any;
println!("{:?}", Any::type_id("foo"));
println!("{:?}", "foo".type_id());
}
fn multi_bad() {
use std::any::{self, Any as _, TypeId};
//~^ unused_trait_names
println!("{:?}", "foo".type_id());
}
fn multi_good() {
use std::any::{self, Any as _, TypeId};
println!("{:?}", "foo".type_id());
}
fn renamed_bad() {
use std::any::Any as _;
//~^ unused_trait_names
println!("{:?}", "foo".type_id());
}
fn multi_renamed_bad() {
use std::any::{Any as _, TypeId as MyTypeId};
//~^ unused_trait_names
println!("{:?}", "foo".type_id());
}
mod pub_good {
pub use std::any::Any;
fn foo() {
println!("{:?}", "foo".type_id());
}
}
mod used_mod_good {
use std::any::Any;
fn foo() {
println!("{:?}", Any::type_id("foo"));
}
}
mod mod_import_bad {
fn mod_import_bad() {
use std::any::Any as _;
//~^ unused_trait_names
println!("{:?}", "foo".type_id());
}
}
mod nested_mod_used_good1 {
use std::any::Any;
mod foo {
fn foo() {
super::Any::type_id("foo");
}
}
}
mod nested_mod_used_good2 {
use std::any::Any;
mod foo {
use super::Any;
fn foo() {
Any::type_id("foo");
}
}
}
mod nested_mod_used_good3 {
use std::any::Any;
mod foo {
use crate::nested_mod_used_good3::Any;
fn foo() {
println!("{:?}", Any::type_id("foo"));
}
}
}
mod nested_mod_used_bad {
use std::any::Any as _;
//~^ unused_trait_names
fn bar() {
println!("{:?}", "foo".type_id());
}
mod foo {
use std::any::Any;
fn foo() {
println!("{:?}", Any::type_id("foo"));
}
}
}
// More complex example where `use std::any::Any;` should be anonymised but `use std::any::Any as
// MyAny;` should not as it is used by a sub module. Even though if you removed `use std::any::Any;`
// the code would still compile.
mod nested_mod_used_bad1 {
use std::any::Any as _;
//~^ unused_trait_names
use std::any::Any as MyAny;
fn baz() {
println!("{:?}", "baz".type_id());
}
mod foo {
use crate::nested_mod_used_bad1::MyAny;
fn foo() {
println!("{:?}", MyAny::type_id("foo"));
}
}
}
// Example of nested import with an unused import to try and trick it
mod nested_mod_used_good5 {
use std::any::Any;
mod foo {
use std::any::Any;
fn baz() {
println!("{:?}", "baz".type_id());
}
mod bar {
use crate::nested_mod_used_good5::foo::Any;
fn foo() {
println!("{:?}", Any::type_id("foo"));
}
}
}
}
mod simple_trait {
pub trait MyTrait {
fn do_things(&self);
}
pub struct MyStruct;
impl MyTrait for MyStruct {
fn do_things(&self) {}
}
}
// Underscore imports were stabilized in 1.33
#[clippy::msrv = "1.32"]
fn msrv_1_32() {
use simple_trait::{MyStruct, MyTrait};
MyStruct.do_things();
}
#[clippy::msrv = "1.33"]
fn msrv_1_33() {
use simple_trait::{MyStruct, MyTrait as _};
//~^ unused_trait_names
MyStruct.do_things();
}
// Linting inside macro expansion is no longer supported
mod lint_inside_macro_expansion_bad {
macro_rules! foo {
() => {
use std::any::Any;
fn bar() {
"bar".type_id();
}
};
}
foo!();
}
mod macro_and_trait_same_name {
pub macro Foo() {}
pub trait Foo {
fn bar(&self);
}
impl Foo for () {
fn bar(&self) {}
}
}
fn call_macro_and_trait_good() {
// importing trait and macro but only using macro by path won't allow us to change this to
// `use macro_and_trait_same_name::Foo as _;`
use macro_and_trait_same_name::Foo;
Foo!();
().bar();
}
proc_macros::external!(
fn ignore_inside_external_proc_macro() {
use std::any::Any;
"foo".type_id();
}
);
proc_macros::with_span!(
span
fn ignore_inside_with_span_proc_macro() {
use std::any::Any;
"foo".type_id();
}
);
// This should warn the import is unused but should not trigger unused_trait_names
#[warn(unused)]
mod unused_import {
//~^ ERROR: unused import
}
#[allow(clippy::unused_trait_names)]
fn allow_lint_fn() {
use std::any::Any;
"foo".type_id();
}
#[allow(clippy::unused_trait_names)]
mod allow_lint_mod {
use std::any::Any;
fn foo() {
"foo".type_id();
}
}
mod allow_lint_import {
#[allow(clippy::unused_trait_names)]
use std::any::Any;
fn foo() {
"foo".type_id();
}
}
// Limitation: Suggests `use std::any::Any as _::{self};` which looks weird
// fn use_trait_self_good() {
// use std::any::Any::{self};
// "foo".type_id();
// }
// Limitation: Suggests `use std::any::{Any as _, Any as _};`
// mod repeated_renamed {
// use std::any::{Any, Any as MyAny};
// fn foo() {
// "foo".type_id();
// }
// }
|
