Prepend generated file root to protobuf input root path.

[rynbrd]

Protobufs generated in a separate repository do not have their root set properly. This causes builds to fail when using well known protos from the latest https://github.com/google/protobuf.

Fixes #312.

I could not find documentation on the right way to join paths in bzl files so have resorted to '/'.join(...). Open to suggestions on a better way to do that.

[bazel-io]

Can one of the admins verify this patch?

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[rynbrd]

I signed it!

[googlebot]

CLAs look good, thanks!

[johnynek]

I don't know a better way to fix this.

Looks good to me.

[ittaiz]

Not sure this will work for windows, I'll merge since I think it's better than before
@damienmg is there a better way to handle this problem?

[damienmg]

Unfortunately not at the moment.

[ittaiz]

I see. So if we wanted to support windows you'd suggest just doing an if there and use relevant separators?

[damienmg]

I believe people have open sourced skylib ( https://github.com/bazelbuild/bazel-skylib) for exactly those kind of base functions. Cc @dslomov also for windows and Skylark.

…

On Tue, Oct 24, 2017, 8:25 AM Ittai Zeidman ***@***.***> wrote: I see. So if we wanted to support windows you'd suggest just doing an if there and use relevant separators? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#321 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ADjHf8g0eBTV0x8x21fHCMt9eK1KCvMMks5svYLzgaJpZM4QDb3a> .

[ittaiz]

Thanks, skylib definitely looks interesting though they declare they don't support windows yet