On Wed, Dec 1, 2021 at 3:33 AM Fabian Stelzer <fs@xxxxxxxxxxxx> wrote: > On 01.12.2021 00:32, Eric Sunshine wrote: > >+ We make a distinction between a command's primary output and output > >+ which is merely chatty feedback (for instance, status messages, > >+ running transcript, or progress display), as well as error messages. > >+ Roughly speaking, a command's primary output is that which one might > >+ want to capture to a file or send down a pipe; its chatty output > >+ should not interfere with those use-cases. > >+ > >+ As such, primary output should be sent to the standard output stream > >+ (stdout), and chatty output should be sent to the standard error > >+ stream (stderr). Examples of commands which produce primary output > >+ include `git log`, `git show`, and `git branch --list` which generate > >+ output on the stdout stream. > >+ > >+ Not all commands have primary output; this is often true of commands > >+ whose main function is to perform an action. Some action commands are > >+ silent, whereas others are chatty. An example of a chatty action > >+ commands is `git clone` with its "Cloning into '<path>'..." and > >+ "Checking connectivity..." status messages which it sends to the > >+ stderr stream. > >+ > >+ Error messages are always sent to the stderr stream. > > This is not necessarily true in the context of the tests. > We just spoke about this in: > https://lore.kernel.org/git/211130.86wnkpd6ou.gmgdl@xxxxxxxxxxxxxxxxxxx/T/#u > > I don't think it necessary to bloat this explanation with the test details. > But mentioning it as an exception would be good. Yep, I tried to be clear about that by repeatedly stating that _command_ output should follow this guideline, where "command" means "Git command". I strongly considered writing "Git command" to be perfectly clear, but figured reviewers would insist that it was redundant to mention "Git". However, I can certainly change these to say "Git command" if you think it would make the intent clearer, and can update the final point to say: Error messages from Git commands should always be sent to the stderr stream.
