Regression in 1.26: Cargo.toml parsing of a crate fails

[pietroalbini]

• polylabel_cmd regressed from stable to beta (build log) cc @urschrei

error: failed to parse manifest at `/source/Cargo.toml`

Caused by:
  the target `polylabel` is a binary and can't have any crate-types set (currently "bin")

[Mark-Simulacrum]

cc @matklad @alexcrichton (possibly fixed since then, this is beta.2)

[pietroalbini]

That's still happening in beta.3 (latest one available in rustup):

pietro@january: ~/tmp/polylabel_cmd$ rustc +beta --version                               
rustc 1.26.0-beta.3 (8a75d2b50 2018-04-08)                                               
pietro@january: ~/tmp/polylabel_cmd$ cargo +beta build                                   
error: failed to parse manifest at `/home/pietro/tmp/polylabel_cmd/Cargo.toml`           
                                                                                         
Caused by:                                                                               
  the target `polylabel` is a binary and can't have any crate-types set (currently "bin")
pietro@january: ~/tmp/polylabel_cmd$                                                     

[matklad]

So, this was introduced in rust-lang/cargo#5204, and it is semi-intentional: the error here would happen only if you build the crate directly, it's OK to use it as a dependency. cargo +beta install polylabel_cmd also works fine. At that time, we've grepped through crates.io and haven't actually found any crates affected by this. But looks like we haven't grepped accurately enough :-) If this is the only regression with this error, I suggest to stick to status quo.

[alexcrichton]

Thanks for the diagnosis @matklad! Your conclusion sounds good to me

[urschrei]

Nbd for the crate either; I’ll push an update when I get a sec.

…

-- steph

On 13 Apr 2018, at 18:44, Alex Crichton ***@***.***> wrote: Thanks for the diagnosis @matklad! Your conclusion sounds good to me — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[lukaslueg]

The grep in rust-lang/cargo#5204 was done on a copy of crates.io that didnt yet have polylabel_cmd in it. A version from mid-march only finds polylabel_cmd.

[alexcrichton]

I'm going to close this due to @matklad's comment, but if there are any issues in updating crates please let us know!