Avoid unhelpful suggestion when crate name is invalid

[workingjubilee]

Pointing out they can set the crate's name is non-actionable: their problem is they found out how and set it incorrectly. Remove extraneous information that can only confuse the matter.

Fixes #150023

[rustbot]

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[jieyouxu]

Thanks

View changes since this review

[jieyouxu]

r? me
r=me once PR CI is green.

[fmease]

Did you mean to link this PR to issue #150023?

[workingjubilee]

Yes!

[workingjubilee]

@bors r=jieyouxu rollup

[bors]

📌 Commit b19d781 has been approved by jieyouxu

It is now in the queue for this repository.

[jieyouxu]

Unfortunately this accrued a merge conflict in the mean time.
@bors r-

[bors]

☔ The latest upstream changes (presumably #150068) made this pull request unmergeable. Please resolve the merge conflicts.

[workingjubilee]

RIP

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[workingjubilee]

@bors r=jieyouxu

[bors]

📌 Commit 25cc98f has been approved by jieyouxu

It is now in the queue for this repository.

[schuelermine]

The documentation should also be updated to reflect the fact that name has to be a valid crate name in the first place. This is not mentioned in the documentation. The documentation only says that the [lib] target uses the name property as Rust identifier.

[workingjubilee]

@schuelermine Er, can you elaborate on what is missing?

[schuelermine]

https://doc.rust-lang.org/cargo/reference/cargo-targets.html#the-name-field

This is the only part of the Cargo docs I could find that talks about the name field, and it does not mention at all that it has to be a valid Rust identifier.

It does (implicitly) state that it has to be a valid Rust identifier for libraries, with the sentence “For a library, this is the crate name that dependencies will use to reference it.”, but there is nothing in here that would make me expect that e.g. ??? is an invalid name for a [[bin]] target.

[fmease]

This docs issue should be submitted to Cargo's issue tracker (https://github.com/rust-lang/cargo/issues) unless it's already been reported over there. This repository doesn't really track Cargo-specific matters.

[fmease]

Although the rustc book (https://doc.rust-lang.org/rustc/index.html) has a similar issue, it doesn't precisely specify what constitutes a valid crate name for e.g., --crate-name (see https://doc.rust-lang.org/rustc/command-line-arguments.html#--crate-name-specify-the-name-of-the-crate-being-built) or --extern (https://doc.rust-lang.org/rustc/command-line-arguments.html#--crate-name-specify-the-name-of-the-crate-being-built).

That could be worth opening issue for, here in r-l/r (unless one already exists). Fun fact, --crate-name and --extern understand something different by crate name (the former also admits digit-prefixed names and the latter only admits "ASCII identifiers").