On Fri, Nov 20, 2020 at 8:49 AM Eric Sunshine <sunshine@xxxxxxxxxxxxxx> wrote: > > On Fri, Nov 20, 2020 at 1:38 AM Eric Sunshine <sunshine@xxxxxxxxxxxxxx> wrote: > > I do find it quite concerning that the way this series handles the > > stdin conflict between the hook and `-F -` can break the hook silently > > and mysteriously. How confusing for a user to write a hook which works > > with `git commit -m msg` and `git commit -F file` but breaks silently > > with `git commit -F -`. What is worse is that this breakage may be > > outside the user's control. For instance, it is easy to imagine some > > IDE passing the commit message to git-commit via stdin (using `-F -`) > > rather than via a file (using `-F file`). > > > > At the very least, this change deserves a documentation update, both > > to explain that the prepare-commit-msg hook has a valid stdin, and > > (importantly) that it won't be able to rely upon stdin in conjunction > > with `-F -`. > > What I forgot to say here was that this patch series doesn't help > users at all if their IDE passes the commit message to git-commit via > stdin using `-F -`. In such a case, their hook will _never_ see a > valid stdin coming from Git, no matter what their script does. So, the > change made by this patch series may help some users but not others, > and this is a limitation that should be stated in the commit message > (and perhaps mentioned in the documentation, though that may be > difficult to do in a general way). At least in my case, I never expect stdin to be available when running in the IDE, so my hook is expected to use GUI anyway. I only need stdin when the user is running git from the terminal. So all I need from the IDE is that it doesn't pretend to be a tty while running Git. And regarding the hook itself - the hook author should be aware that stdin is not always a tty, and sometimes can be closed or pipe, and write the hook in a way that handles special cases. - Orgad
