to_owned should be used in favor of to_string

[leaexplores]

Hi, this PR stumbles upon a small nit I covered while seeking some code in cocoa-rs and servo.

It fixes the to_string calls for to_owned. It is much lighter in resources.

To_string as uses the whole formatting machinery just to clone a string.

Thanks for looking into it !

[leaexplores]

ping? @SSheldon

[SSheldon]

Hey @ddrmanxbxfr, this looks fine but I'm curious if to_owned is now the most idiomatic way to do this conversion. In rust-lang/rust#26176, some of the rust core team claims to_string is more idiomatic and semantically correct.

Since into_string was removed, I'd been under the impression that to_string was the correct way to convert a str into a String, and that it would eventually be optimized to avoid the cost.

Do you think this code is more idiomatic with to_owned? Or, if not, does the performance improvement here seem worth it anyways?

[SSheldon]

Ping @ddrmanxbxfr! I could use your help here figuring out what's the best way to convert to a String :)

[leaexplores]

Hi @SSheldon my bad I was PTO for a few days.

to_string does feel more indiomatic and semantically correct.

However as of right now to_string does come with a runtime overhead and to_owned should be used in this case.

Here's an example issue : rust-lang/rust#18404

Rust clippy (a rust linter) also checks to use to_owned in favor of to_string : https://github.com/Manishearth/rust-clippy/wiki#str_to_string

May we see a merge between to_owned and to_string when to_string will be up par the performance level of to_owned.

[SSheldon]

Oh I didn't realize rust-clippy had a lint for this, that's a pretty strong point in favor of to_owned. Thanks, merging this!