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Add run-rustfix to unnecessary_fold

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This commit is contained in:
Wilco Kusee 2019-01-13 20:03:22 +01:00
parent c325137d08
commit 51c0dd427b
3 changed files with 62 additions and 14 deletions
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44
tests/ui/unnecessary_fold.fixed Normal file
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@ -0,0 +1,44 @@
// run-rustfix
#![allow(dead_code)]
/// Calls which should trigger the `UNNECESSARY_FOLD` lint
fn unnecessary_fold() {
// Can be replaced by .any
let _ = (0..3).any(|x| x > 2);
// Can be replaced by .all
let _ = (0..3).all(|x| x > 2);
// Can be replaced by .sum
let _: i32 = (0..3).sum();
// Can be replaced by .product
let _: i32 = (0..3).product();
}
/// Should trigger the `UNNECESSARY_FOLD` lint, with an error span including exactly `.fold(...)`
fn unnecessary_fold_span_for_multi_element_chain() {
let _: bool = (0..3).map(|x| 2 * x).any(|x| x > 2);
}
/// Calls which should not trigger the `UNNECESSARY_FOLD` lint
fn unnecessary_fold_should_ignore() {
let _ = (0..3).fold(true, |acc, x| acc || x > 2);
let _ = (0..3).fold(false, |acc, x| acc && x > 2);
let _ = (0..3).fold(1, |acc, x| acc + x);
let _ = (0..3).fold(0, |acc, x| acc * x);
let _ = (0..3).fold(0, |acc, x| 1 + acc + x);
// We only match against an accumulator on the left
// hand side. We could lint for .sum and .product when
// it's on the right, but don't for now (and this wouldn't
// be valid if we extended the lint to cover arbitrary numeric
// types).
let _ = (0..3).fold(false, |acc, x| x > 2 || acc);
let _ = (0..3).fold(true, |acc, x| x > 2 && acc);
let _ = (0..3).fold(0, |acc, x| x + acc);
let _ = (0..3).fold(1, |acc, x| x * acc);
let _ = [(0..2), (0..3)].iter().fold(0, |a, b| a + b.len());
let _ = [(0..2), (0..3)].iter().fold(1, |a, b| a * b.len());
}
fn main() {}

10
tests/ui/unnecessary_fold.rs
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@ -1,3 +1,7 @@
// run-rustfix
#![allow(dead_code)]
/// Calls which should trigger the `UNNECESSARY_FOLD` lint
fn unnecessary_fold() {
// Can be replaced by .any
@ -5,14 +9,14 @@ fn unnecessary_fold() {
// Can be replaced by .all
let _ = (0..3).fold(true, |acc, x| acc && x > 2);
// Can be replaced by .sum
let _ = (0..3).fold(0, |acc, x| acc + x);
let _: i32 = (0..3).fold(0, |acc, x| acc + x);
// Can be replaced by .product
let _ = (0..3).fold(1, |acc, x| acc * x);
let _: i32 = (0..3).fold(1, |acc, x| acc * x);
}
/// Should trigger the `UNNECESSARY_FOLD` lint, with an error span including exactly `.fold(...)`
fn unnecessary_fold_span_for_multi_element_chain() {
let _ = (0..3).map(|x| 2 * x).fold(false, |acc, x| acc || x > 2);
let _: bool = (0..3).map(|x| 2 * x).fold(false, |acc, x| acc || x > 2);
}
/// Calls which should not trigger the `UNNECESSARY_FOLD` lint

22
tests/ui/unnecessary_fold.stderr
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@ -1,5 +1,5 @@
error: this `.fold` can be written more succinctly using another method
--> $DIR/unnecessary_fold.rs:4:19
--> $DIR/unnecessary_fold.rs:8:19
|
LL | let _ = (0..3).fold(false, |acc, x| acc || x > 2);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.any(|x| x > 2)`
@ -7,28 +7,28 @@ LL | let _ = (0..3).fold(false, |acc, x| acc || x > 2);
= note: `-D clippy::unnecessary-fold` implied by `-D warnings`
error: this `.fold` can be written more succinctly using another method
--> $DIR/unnecessary_fold.rs:6:19
--> $DIR/unnecessary_fold.rs:10:19
|
LL | let _ = (0..3).fold(true, |acc, x| acc && x > 2);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.all(|x| x > 2)`
error: this `.fold` can be written more succinctly using another method
--> $DIR/unnecessary_fold.rs:8:19
--> $DIR/unnecessary_fold.rs:12:24
|
LL | let _ = (0..3).fold(0, |acc, x| acc + x);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.sum()`
LL | let _: i32 = (0..3).fold(0, |acc, x| acc + x);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.sum()`
error: this `.fold` can be written more succinctly using another method
--> $DIR/unnecessary_fold.rs:10:19
--> $DIR/unnecessary_fold.rs:14:24
|
LL | let _ = (0..3).fold(1, |acc, x| acc * x);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.product()`
LL | let _: i32 = (0..3).fold(1, |acc, x| acc * x);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.product()`
error: this `.fold` can be written more succinctly using another method
--> $DIR/unnecessary_fold.rs:15:34
--> $DIR/unnecessary_fold.rs:19:40
|
LL | let _ = (0..3).map(|x| 2 * x).fold(false, |acc, x| acc || x > 2);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.any(|x| x > 2)`
LL | let _: bool = (0..3).map(|x| 2 * x).fold(false, |acc, x| acc || x > 2);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.any(|x| x > 2)`
error: aborting due to 5 previous errors