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#![warn(clippy::manual_is_power_of_two)]
#![allow(clippy::precedence)]
macro_rules! binop {
($a: expr, equal, $b: expr) => {
$a == $b
};
($a: expr, and, $b: expr) => {
$a & $b
};
($a: expr, minus, $b: expr) => {
$a - $b
};
}
fn main() {
let a = 16_u64;
let _ = a.count_ones() == 1;
//~^ manual_is_power_of_two
let _ = u64::count_ones(a) == 1;
//~^ manual_is_power_of_two
let _ = a & (a - 1) == 0;
//~^ manual_is_power_of_two
// Test different orders of expression
let _ = 1 == a.count_ones();
//~^ manual_is_power_of_two
let _ = (a - 1) & a == 0;
//~^ manual_is_power_of_two
let _ = 0 == a & (a - 1);
//~^ manual_is_power_of_two
let _ = 0 == (a - 1) & a;
//~^ manual_is_power_of_two
let b = 4_i64;
// is_power_of_two only works for unsigned integers
let _ = b.count_ones() == 1;
let _ = b & (b - 1) == 0;
let i: i32 = 3;
let _ = i as u32 & (i as u32 - 1) == 0;
//~^ manual_is_power_of_two
let _ = binop!(a.count_ones(), equal, 1);
let _ = binop!(a, and, a - 1) == 0;
let _ = a & binop!(a, minus, 1) == 0;
}
#[clippy::msrv = "1.31"]
const fn low_msrv(a: u32) -> bool {
a & (a - 1) == 0
}
#[clippy::msrv = "1.32"]
const fn high_msrv(a: u32) -> bool {
a & (a - 1) == 0
//~^ manual_is_power_of_two
}
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