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|
#![warn(clippy::useless_vec)]
#![allow(clippy::nonstandard_macro_braces, clippy::uninlined_format_args, unused)]
use std::rc::Rc;
struct StructWithVec {
_x: Vec<i32>,
}
fn on_slice(_: &[u8]) {}
fn on_mut_slice(_: &mut [u8]) {}
#[allow(clippy::ptr_arg)]
fn on_vec(_: &Vec<u8>) {}
fn on_mut_vec(_: &mut Vec<u8>) {}
struct Line {
length: usize,
}
impl Line {
fn length(&self) -> usize {
self.length
}
}
fn main() {
on_slice(&vec![]);
//~^ useless_vec
on_slice(&[]);
on_mut_slice(&mut vec![]);
//~^ useless_vec
on_slice(&vec![1, 2]);
//~^ useless_vec
on_slice(&[1, 2]);
on_mut_slice(&mut vec![1, 2]);
//~^ useless_vec
on_slice(&vec![1, 2]);
//~^ useless_vec
on_slice(&[1, 2]);
on_mut_slice(&mut vec![1, 2]);
//~^ useless_vec
#[rustfmt::skip]
on_slice(&vec!(1, 2));
//~^ useless_vec
on_slice(&[1, 2]);
on_mut_slice(&mut vec![1, 2]);
//~^ useless_vec
on_slice(&vec![1; 2]);
//~^ useless_vec
on_slice(&[1; 2]);
on_mut_slice(&mut vec![1; 2]);
//~^ useless_vec
on_vec(&vec![]);
on_vec(&vec![1, 2]);
on_vec(&vec![1; 2]);
on_mut_vec(&mut vec![]);
on_mut_vec(&mut vec![1, 2]);
on_mut_vec(&mut vec![1; 2]);
// Now with non-constant expressions
let line = Line { length: 2 };
on_slice(&vec![2; line.length]);
on_slice(&vec![2; line.length()]);
on_mut_slice(&mut vec![2; line.length]);
on_mut_slice(&mut vec![2; line.length()]);
on_vec(&vec![1; 201]); // Ok, size of `vec` higher than `too_large_for_stack`
on_mut_vec(&mut vec![1; 201]); // Ok, size of `vec` higher than `too_large_for_stack`
// Ok
for a in vec![1; 201] {
println!("{:?}", a);
}
// https://github.com/rust-lang/rust-clippy/issues/2262#issuecomment-783979246
let _x: i32 = vec![1, 2, 3].iter().sum();
//~^ useless_vec
// Do lint
let mut x = vec![1, 2, 3];
//~^ useless_vec
x.fill(123);
dbg!(x[0]);
dbg!(x.len());
dbg!(x.iter().sum::<i32>());
let _x: &[i32] = &vec![1, 2, 3];
//~^ useless_vec
for _ in vec![1, 2, 3] {}
//~^ useless_vec
// Don't lint
let x = vec![1, 2, 3];
let _v: Vec<i32> = x;
let x = vec![1, 2, 3];
let _s = StructWithVec { _x: x };
// Explicit type annotation would make the change to [1, 2, 3]
// a compile error.
let _x: Vec<i32> = vec![1, 2, 3];
// Calling a Vec method through a mutable reference
let mut x = vec![1, 2, 3];
let re = &mut x;
re.push(4);
// Comparing arrays whose length is not equal is a compile error
let x = vec![1, 2, 3];
let y = vec![1, 2, 3, 4];
dbg!(x == y);
// Non-copy types
let _x = vec![String::new(); 10];
#[allow(clippy::rc_clone_in_vec_init)]
let _x = vec![Rc::new(1); 10];
// Too large
let _x = vec![1; 201];
}
fn issue11075() {
macro_rules! repro {
($e:expr) => {
stringify!($e)
};
}
#[allow(clippy::never_loop)]
for _string in vec![repro!(true), repro!(null)] {
//~^ useless_vec
unimplemented!();
}
macro_rules! in_macro {
($e:expr, $vec:expr, $vec2:expr) => {{
vec![1; 2].fill(3);
vec![1, 2].fill(3);
for _ in vec![1, 2] {}
for _ in vec![1; 2] {}
for _ in vec![$e, $e] {}
for _ in vec![$e; 2] {}
for _ in $vec {}
for _ in $vec2 {}
}};
}
in_macro!(1, vec![1, 2], vec![1; 2]);
//~^ useless_vec
//~| useless_vec
macro_rules! from_macro {
() => {
vec![1, 2, 3]
};
}
macro_rules! from_macro_repeat {
() => {
vec![1; 3]
};
}
for _ in from_macro!() {}
for _ in from_macro_repeat!() {}
}
#[clippy::msrv = "1.53"]
fn above() {
for a in vec![1, 2, 3] {
//~^ useless_vec
let _: usize = a;
}
for a in vec![String::new(), String::new()] {
//~^ useless_vec
let _: String = a;
}
}
#[clippy::msrv = "1.52"]
fn below() {
for a in vec![1, 2, 3] {
let _: usize = a;
}
for a in vec![String::new(), String::new()] {
let _: String = a;
}
}
fn func_needing_vec(_bar: usize, _baz: Vec<usize>) {}
fn func_not_needing_vec(_bar: usize, _baz: usize) {}
fn issue11861() {
macro_rules! this_macro_needs_vec {
($x:expr) => {{
func_needing_vec($x.iter().sum(), $x);
for _ in $x {}
}};
}
macro_rules! this_macro_doesnt_need_vec {
($x:expr) => {{ func_not_needing_vec($x.iter().sum(), $x.iter().sum()) }};
}
// Do not lint the next line
this_macro_needs_vec!(vec![1]);
this_macro_doesnt_need_vec!(vec![1]);
//~^ useless_vec
macro_rules! m {
($x:expr) => {
fn f2() {
let _x: Vec<i32> = $x;
}
fn f() {
let _x = $x;
$x.starts_with(&[]);
}
};
}
// should not lint
m!(vec![1]);
}
fn issue_11958() {
fn f(_s: &[String]) {}
// should not lint, `String` is not `Copy`
f(&vec!["test".to_owned(); 2]);
}
fn issue_12101() {
for a in &(vec![1, 2]) {}
//~^ useless_vec
}
|
