"rustup target add" fails for required components

[alexcrichton]

If you rustup target add for the host toolchain's standard library it returns an error, but for scripting it'd be nice if it just said "OK" instead perhaps?

[brson]

Yep.

[SWW13]

Adding rustup output for easier search: (I almost overlooked this issue)

$ rustup target add aarch64-unknown-linux-gnu      
info: component 'rust-std' for target 'aarch64-unknown-linux-gnu' is up to date

$ rustup target add x86_64-unknown-linux-gnu       
error: component 'rust-std' for target 'x86_64-unknown-linux-gnu' was automatically added because it is required for toolchain 'stable-x86_64-unknown-linux-gnu'

[agausmann]

2 years later, and I just encountered a CI error for this. Did this issue get lost?

[Folyd]

The same error on travis-ci:

$ if [[ $TRAVIS_OS_NAME = linux && $HOST != $TARGET ]]; then rustup target add $TARGET; fi
error: component 'rust-std' for target 'x86_64-unknown-linux-gnu' was automatically added because it is required for toolchain 'stable-x86_64-unknown-linux-gnu'

[nre-ableton]

Ditto. I'm seeing this error on our Windows build nodes:

+ rustup.exe target add x86_64-pc-windows-msvc
error: component 'rust-std' for target 'x86_64-pc-windows-msvc' was automatically added because it is required for toolchain 'stable-x86_64-pc-windows-msvc'

Very confusing error message IMHO; I'm really not sure why this command would fail with an error that sounds like a success message.

Edit: Related https://github.com/rust-lang-nursery/rustup.rs/pull/1255/files. IMHO the message was clearer before this PR, but that's just my opinion... 😄