The "unused manifest key" warning doesn't print or halt the publishing with cargo publish

[Lokathor]

Normally if you have a manifest key that cargo doesn't understand many of the commands will print a warning

D:\dev\cargo-gba>cargo build
warning: unused manifest key: package.repsitory

However, if you use cargo publish not only does the accidental key not halt the publishing process without an override flag (as one might expect, similar to how you can't publish with a dirty git state without a flag), but it doesn't even directly print the warning about a bad key. Instead I got the warning about "no documentation, homepage or repository."

D:\dev\cargo-gba>cargo publish
    Updating crates.io index
warning: manifest has no documentation, homepage or repository.
See https://doc.rust-lang.org/cargo/reference/manifest.html#package-metadata for more info.

[jonas-schievink]

Please file this at https://github.com/rust-lang/cargo