rust-clippy/tests/ui/map_clone.stderr
Michael Wright 67a9f20c91 Fix map_clone bad suggestion
`cloned` requires that the elements of the iterator must be references. This
change determines if that is the case by examining the type of the closure
argument and suggesting `.cloned` only if it is a reference. When the closure
argument is not a reference, it suggests removing the `map` call instead.

A minor problem with this change is that the new check sometimes overlaps
with the `clone_on_copy` lint.

Fixes #498
2019-01-15 08:09:47 +02:00

28 lines
1.3 KiB
Text

error: You are using an explicit closure for cloning elements
--> $DIR/map_clone.rs:8:22
|
LL | let _: Vec<i8> = vec![5_i8; 6].iter().map(|x| *x).collect();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Consider calling the dedicated `cloned` method: `vec![5_i8; 6].iter().cloned()`
|
= note: `-D clippy::map-clone` implied by `-D warnings`
error: You are using an explicit closure for cloning elements
--> $DIR/map_clone.rs:9:26
|
LL | let _: Vec<String> = vec![String::new()].iter().map(|x| x.clone()).collect();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Consider calling the dedicated `cloned` method: `vec![String::new()].iter().cloned()`
error: You are using an explicit closure for cloning elements
--> $DIR/map_clone.rs:10:23
|
LL | let _: Vec<u32> = vec![42, 43].iter().map(|&x| x).collect();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Consider calling the dedicated `cloned` method: `vec![42, 43].iter().cloned()`
error: You are needlessly cloning iterator elements
--> $DIR/map_clone.rs:22:29
|
LL | let _ = std::env::args().map(|v| v.clone());
| ^^^^^^^^^^^^^^^^^^^ help: Remove the map call
error: aborting due to 4 previous errors