Re: [PATCH] CodingGuidelines: document which output goes to stdout vs. stderr

[Fabian Stelzer <fs@gigacodes.de>]

On 01.12.2021 08:50, Eric Sunshine wrote:
>On Wed, Dec 1, 2021 at 3:33 AM Fabian Stelzer <fs@gigacodes.de> 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@evledraar.gmail.com/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.

Maybe it was just because i was working on test-lib stuff earlier that i did 
not connect `a commands output` to a `git command` but basically understood 
it as all output in git code.
Still, I think your addition to the last sentence is a good idea and won't 
hurt.

Thanks