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|
#![warn(clippy::needless_range_loop, clippy::manual_memcpy)]
const LOOP_OFFSET: usize = 5000;
pub fn manual_copy(src: &[i32], dst: &mut [i32], dst2: &mut [i32]) {
// plain manual memcpy
for i in 0..src.len() {
dst[i] = src[i];
}
// dst offset memcpy
for i in 0..src.len() {
dst[i + 10] = src[i];
}
// src offset memcpy
for i in 0..src.len() {
dst[i] = src[i + 10];
}
// src offset memcpy
for i in 11..src.len() {
dst[i] = src[i - 10];
}
// overwrite entire dst
for i in 0..dst.len() {
dst[i] = src[i];
}
// manual copy with branch - can't easily convert to memcpy!
for i in 0..src.len() {
dst[i] = src[i];
if dst[i] > 5 {
break;
}
}
// multiple copies - suggest two memcpy statements
for i in 10..256 {
dst[i] = src[i - 5];
dst2[i + 500] = src[i]
}
// this is a reversal - the copy lint shouldn't be triggered
for i in 10..LOOP_OFFSET {
dst[i + LOOP_OFFSET] = src[LOOP_OFFSET - i];
}
let some_var = 5;
// Offset in variable
for i in 10..LOOP_OFFSET {
dst[i + LOOP_OFFSET] = src[i - some_var];
}
// Non continuous copy - don't trigger lint
for i in 0..10 {
dst[i + i] = src[i];
}
let src_vec = vec![1, 2, 3, 4, 5];
let mut dst_vec = vec![0, 0, 0, 0, 0];
// make sure vectors are supported
for i in 0..src_vec.len() {
dst_vec[i] = src_vec[i];
}
// lint should not trigger when either
// source or destination type is not
// slice-like, like DummyStruct
struct DummyStruct(i32);
impl ::std::ops::Index<usize> for DummyStruct {
type Output = i32;
fn index(&self, _: usize) -> &i32 {
&self.0
}
}
let src = DummyStruct(5);
let mut dst_vec = vec![0; 10];
for i in 0..10 {
dst_vec[i] = src[i];
}
// Simplify suggestion (issue #3004)
let src = [0, 1, 2, 3, 4];
let mut dst = [0, 0, 0, 0, 0, 0];
let from = 1;
for i in from..from + src.len() {
dst[i] = src[i - from];
}
for i in from..from + 3 {
dst[i] = src[i - from];
}
#[allow(clippy::identity_op)]
for i in 0..5 {
dst[i - 0] = src[i];
}
#[allow(clippy::reversed_empty_ranges)]
for i in 0..0 {
dst[i] = src[i];
}
// `RangeTo` `for` loop - don't trigger lint
for i in 0.. {
dst[i] = src[i];
}
// VecDeque - ideally this would work, but would require something like `range_as_slices`
let mut dst = std::collections::VecDeque::from_iter([0; 5]);
let src = std::collections::VecDeque::from_iter([0, 1, 2, 3, 4]);
for i in 0..dst.len() {
dst[i] = src[i];
}
let src = vec![0, 1, 2, 3, 4];
for i in 0..dst.len() {
dst[i] = src[i];
}
}
#[warn(clippy::needless_range_loop, clippy::manual_memcpy)]
pub fn manual_clone(src: &[String], dst: &mut [String]) {
for i in 0..src.len() {
dst[i] = src[i].clone();
}
}
fn main() {}
|
