to_string is perhaps more idiomatic

[hoodie]

Currently there is https://github.com/Manishearth/rust-clippy/wiki#str_to_string and it tells you that to_string() is slow. Should a lint warn people about this? As soon as specializations lands there will be no difference and you could argue that &str.to_owned() is not idiomatic, so there might be a lint that contradicts an earlier lint.

What do you think?

[mcarton]

As soon as specializations lands

Isn’t it the case already? (since a few days, in nightly and modulo an actual specialization of str::to_string 😅 )
We should probably deprecate that lint yes. Ref #728 and #743.

[llogiq]

Not everyone – even those using clippy – develops against nightly.

Also I don't consider neither .to_string() nor .to_owned() un-idiomatic. Still, I agree we should deprecate that lint.