Remove conversion from hyphen to underscore

[hskang9]

resolves cargo's #2775 issue

[rust-highfive]

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[carols10cents]

Hi, sorry, but I think there's a misunderstanding. Fixing rust-lang/cargo#2775 means that whether a Cargo.toml file says crate-name or crate_name, it will resolve to the one crate with crate_name on crates.io. This PR would have the effect of allowing the publishing of both crate-name and crate_name as different crates, which would be potentially confusing.

[hskang9]

Well making - and _ different name was what I was trying to do, but if that creates a confusion then, I should not make this pr. But here is the confusion happening in cargo side. For example, I uploaded cargo package ‘hyphen-example’ but crates.io considers it as ‘hyphen_example’. So I should be able to import package writing “hyphen_example” but running cargo install ‘hyphen_example’ cannot find the package, but when I run cargo install ‘hyphen-example’ then it successfully installs the package. Should I add same conversion logic in cargo as crates.io applies?

[Eh2406]

Should I add same conversion logic in cargo as crates.io applies?

Short answer: Yes.
Long answer: We need to find a way to do the "conversion logic" for crates.io and not for other registries, or decide to break existing functionality for other registries. We also need to find a way to best support older cargos that do not have the "conversion logic", or decide to break existing users. Neither will be straightforward rust-lang/cargo#2775 (comment)