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|
//@aux-build: proc_macros.rs
//@no-rustfix: overlapping suggestions
#![warn(clippy::unit_arg)]
#![allow(unused_must_use, unused_variables)]
#![allow(
clippy::let_unit_value,
clippy::needless_question_mark,
clippy::never_loop,
clippy::no_effect,
clippy::or_fun_call,
clippy::self_named_constructors,
clippy::uninlined_format_args,
clippy::unnecessary_wraps,
clippy::unused_unit
)]
extern crate proc_macros;
use proc_macros::with_span;
use std::fmt::Debug;
fn foo<T: Debug>(t: T) {
println!("{:?}", t);
}
fn foo3<T1: Debug, T2: Debug, T3: Debug>(t1: T1, t2: T2, t3: T3) {
println!("{:?}, {:?}, {:?}", t1, t2, t3);
}
struct Bar;
impl Bar {
fn bar<T: Debug>(&self, t: T) {
println!("{:?}", t);
}
}
fn baz<T: Debug>(t: T) {
foo(t);
}
trait Tr {
type Args;
fn do_it(args: Self::Args);
}
struct A;
impl Tr for A {
type Args = ();
fn do_it(_: Self::Args) {}
}
struct B;
impl Tr for B {
type Args = <A as Tr>::Args;
fn do_it(args: Self::Args) {
A::do_it(args)
}
}
fn bad() {
foo({
//~^ unit_arg
1;
});
foo(foo(1));
//~^ unit_arg
foo({
//~^ unit_arg
foo(1);
foo(2);
});
let b = Bar;
b.bar({
//~^ unit_arg
1;
});
taking_multiple_units(foo(0), foo(1));
//~^ unit_arg
taking_multiple_units(foo(0), {
//~^ unit_arg
foo(1);
foo(2);
});
taking_multiple_units(
//~^ unit_arg
{
foo(0);
foo(1);
},
{
foo(2);
foo(3);
},
);
// here Some(foo(2)) isn't the top level statement expression, wrap the suggestion in a block
None.or(Some(foo(2)));
//~^ unit_arg
// in this case, the suggestion can be inlined, no need for a surrounding block
// foo(()); foo(()) instead of { foo(()); foo(()) }
foo(foo(()));
//~^ unit_arg
}
fn ok() {
foo(());
foo(1);
foo({ 1 });
foo3("a", 3, vec![3]);
let b = Bar;
b.bar({ 1 });
b.bar(());
question_mark();
let named_unit_arg = ();
foo(named_unit_arg);
baz(());
B::do_it(());
}
fn question_mark() -> Result<(), ()> {
Ok(Ok(())?)?;
Ok(Ok(()))??;
Ok(())
}
#[allow(dead_code)]
mod issue_2945 {
fn unit_fn() -> Result<(), i32> {
Ok(())
}
fn fallible() -> Result<(), i32> {
Ok(unit_fn()?)
}
}
#[allow(dead_code)]
fn returning_expr() -> Option<()> {
Some(foo(1))
//~^ unit_arg
}
fn taking_multiple_units(a: (), b: ()) {}
fn proc_macro() {
with_span!(span taking_multiple_units(unsafe { (); }, 'x: loop { break 'x (); }));
}
fn main() {
bad();
ok();
}
fn issue14857() {
let fn_take_unit = |_: ()| {};
fn some_other_fn(_: &i32) {}
macro_rules! mac {
(def) => {
Default::default()
};
(func $f:expr) => {
$f()
};
(nonempty_block $e:expr) => {{
some_other_fn(&$e);
$e
}};
}
fn_take_unit(mac!(def));
//~^ unit_arg
fn_take_unit(mac!(func Default::default));
//~^ unit_arg
fn_take_unit(mac!(nonempty_block Default::default()));
//~^ unit_arg
}
|
