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//@run-rustfix
#![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![]);
on_slice(&[]);
on_mut_slice(&mut vec![]);
on_slice(&vec![1, 2]);
on_slice(&[1, 2]);
on_mut_slice(&mut vec![1, 2]);
on_slice(&vec![1, 2]);
on_slice(&[1, 2]);
on_mut_slice(&mut vec![1, 2]);
#[rustfmt::skip]
on_slice(&vec!(1, 2));
on_slice(&[1, 2]);
on_mut_slice(&mut vec![1, 2]);
on_slice(&vec![1; 2]);
on_slice(&[1; 2]);
on_mut_slice(&mut vec![1; 2]);
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();
// Do lint
let mut x = vec![1, 2, 3];
x.fill(123);
dbg!(x[0]);
dbg!(x.len());
dbg!(x.iter().sum::<i32>());
let _x: &[i32] = &vec![1, 2, 3];
for _ in vec![1, 2, 3] {}
// 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];
}
#[clippy::msrv = "1.53"]
fn above() {
for a in vec![1, 2, 3] {
let _: usize = a;
}
for a in vec![String::new(), String::new()] {
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;
}
}
|
