Auto merge of #4455 - flip1995:unit_arg_appl, r=phansch

Rework suggestion generation of `unit_arg` lint

Found this bug while running `cargo fix --clippy` on quite a big codebase:

This would replace something like:
```rust
Some(fn_that_actually_does_something(&a, b))
```
with
```rust
Some(())
```
which obviously suppresses side effects.

Since pretty much every expression could have side effects, I think making this suggestion `MaybeIncorrect` is the best thing to do here.

A correct suggestion would be:

```rust
fn_that_actually_does_something(&a, b);
Some(())
```

Somehow the suggestion is not correctly applied to the arguments, when more than one argument is a unit value. I have to look into this a little more, though.

changelog: Fixes suggestion of `unit_arg` lint, so that it suggests semantic equivalent code

Fixes #4741

0 files changed, 0 insertions, 0 deletions