#![allow(clippy::map_with_unused_argument_over_ranges)] #![warn(clippy::repeat_vec_with_capacity)] fn main() { { (0..123).map(|_| Vec::<()>::with_capacity(42)).collect::>(); //~^ ERROR: repeating `Vec::with_capacity` using `vec![x; n]`, which does not retain capacity } { let n = 123; (0..n).map(|_| Vec::<()>::with_capacity(42)).collect::>(); //~^ ERROR: repeating `Vec::with_capacity` using `vec![x; n]`, which does not retain capacity } { macro_rules! from_macro { ($x:expr) => { vec![$x; 123]; }; } // vec expansion is from another macro, don't lint from_macro!(Vec::<()>::with_capacity(42)); } { std::iter::repeat_with(|| Vec::<()>::with_capacity(42)); //~^ ERROR: repeating `Vec::with_capacity` using `iter::repeat`, which does not retain capacity } { macro_rules! from_macro { ($x:expr) => { std::iter::repeat($x) }; } from_macro!(Vec::<()>::with_capacity(42)); } }