Use multipart suggestion in unnecessary_to_owned

[nanvel]

It is related to #13099

What was done:

• removed @no-rustfix from tests/ui/unnecessary_to_owned.rs
• checked for suggestions in src/methods/unnecessary_to_owned.rs (there is already one multipart_suggestion, and I don't see any other)
• ran cargo uibless

I am new to Rust, and this is my first PR.

changelog: none

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[scottgerring]

Hey @nanvel ,

(not the reviewer, but I fixed all the other ones of these).

You need to fix the lint, not the test. The test is intentionally badly structured, and the lint needs to emit a single multipart correction to fix it. Essentially this error here should be collapsed into a multipart:

--> tests/ui/unnecessary_to_owned.rs:223:14
   |
LL |     for t in file_types.to_vec() {
   |              ^^^^^^^^^^^^^^^^^^^
   |
help: use
   |
LL |     for t in file_types {
   |              ~~~~~~~~~~
help: remove any references to the binding
   |
LL -         let path = match get_file_path(&t) {
LL +         let path = match get_file_path(t) {
   |

error: unnecessary use of `to_vec`
  --> tests/ui/unnecessary_to_owned.rs:246:14

The idea is, a lint that has multiple parts that need to be applied at once to be semantically correct needs to be applied as a multipart suggestion. At the moment the lint is providing multiple individual suggestions, the test framework applies them separately - which is why you get multiple output files that are each invalid.

If you look at the linked issue you can check out any of my other PRs to see what I mean!

[nanvel]

@scottgerring thanks for the explanation. I rechecked the code, and it should indeed handle to_vec as well.
Will try to fix tomorrow.

[bors]

☔ The latest upstream changes (presumably 9f4941a) made this pull request unmergeable. Please resolve the merge conflicts.

[nanvel]

@scottgerring, somehow, now it works, not sure why it was generating two fixed before.

[scottgerring]

Hey @nanvel ,

Cool! I think it is because the issue with this test happened to be the same issue in the unnecessary_iter_cloned lint, which I fixed for that test yesterday (check out around combined to see the "important bit" - what was two suggestions is now one).

Apologies - I didn't realize this was the only bit touching this test too - I would've expected unnecessary_to_owned to need a multipart change, but looking at it it seems that it's already good.

Again, not the reviewer, but TL;DR enabling the test like you've done and checking those bits in I think should be it 🙌 You might want to squash your commits together with a sensible message( I think it's always a merge into master here) and ping the reviewer !

[flip1995]

I'm trusting @scottgerring assessment that this enough to fix the issue. You worked the most on this topic. Thanks for investigating!

Please squash your commits and this is ready to get merged.

[nanvel]

@flip1995 commits were squashed.