rust/tests/ui/indexing_slicing_index.rs

78 lines
2.2 KiB
Rust

#![feature(inline_const)]
#![warn(clippy::indexing_slicing)]
// We also check the out_of_bounds_indexing lint here, because it lints similar things and
// we want to avoid false positives.
#![warn(clippy::out_of_bounds_indexing)]
#![allow(
unconditional_panic,
clippy::no_effect,
clippy::unnecessary_operation,
clippy::useless_vec
)]
const ARR: [i32; 2] = [1, 2];
const REF: &i32 = &ARR[idx()]; // This should be linted, since `suppress-restriction-lint-in-const` default is false.
//~^ ERROR: indexing may panic
const REF_ERR: &i32 = &ARR[idx4()]; // Ok, let rustc handle const contexts.
//~^ ERROR: indexing may panic
const fn idx() -> usize {
1
}
const fn idx4() -> usize {
4
}
fn main() {
let x = [1, 2, 3, 4];
let index: usize = 1;
x[index];
//~^ ERROR: indexing may panic
// Ok, let rustc's `unconditional_panic` lint handle `usize` indexing on arrays.
x[4];
// Ok, let rustc's `unconditional_panic` lint handle `usize` indexing on arrays.
x[1 << 3];
// Ok, should not produce stderr.
x[0];
// Ok, should not produce stderr.
x[3];
// Ok, should not produce stderr.
x[const { idx() }];
// Ok, let rustc's `unconditional_panic` lint handle `usize` indexing on arrays.
x[const { idx4() }];
// This should be linted, since `suppress-restriction-lint-in-const` default is false.
const { &ARR[idx()] };
//~^ ERROR: indexing may panic
// This should be linted, since `suppress-restriction-lint-in-const` default is false.
const { &ARR[idx4()] };
//~^ ERROR: indexing may panic
let y = &x;
// Ok, referencing shouldn't affect this lint. See the issue 6021
y[0];
// Ok, rustc will handle references too.
y[4];
let v = vec![0; 5];
v[0];
//~^ ERROR: indexing may panic
v[10];
//~^ ERROR: indexing may panic
v[1 << 3];
//~^ ERROR: indexing may panic
// Out of bounds
const N: usize = 15;
// In bounds
const M: usize = 3;
// Ok, let rustc's `unconditional_panic` lint handle `usize` indexing on arrays.
x[N];
// Ok, should not produce stderr.
x[M];
v[N];
//~^ ERROR: indexing may panic
v[M];
//~^ ERROR: indexing may panic
}