From: Chris Packham <judge.packham@gmail.com>
Date: Thu, 01 Oct 2015 03:42:58 GMT
Subject: [BUG?] applypatch-msg hook no-longer thinks stdin is a tty
Message-ID: <CAFOYHZArBv=2E_YonCqOSC4mWk9=xkbG9FyB+zNFFAqmUBUKHA@mail.gmail.com>

Hi,

I have a applypatch-msg hook that implements some policy for
acceptable commit messages and reject non-conformant patches. It also
is able to prompt me to override it's rejection. The prompting only
happens when stdin is a tty (as determined by pythons
sys.stdin.isatty())

For example this would reject the patch and cause am stop
 $ cat bad.patch | git am

And this would prompt me to allow the patch and am would proceed if I answer Y
  $ git am bad.patch
  Patch message invalid apply (Y/N)?

As of git 2.6 this has stopped working and stdin always fails the tty
check. Here's a minimal reproduction

$ cat >.git/hooks/applypatch-msg <<EOF
#!/usr/bin/env python
import sys
if sys.stdin.isatty():
    print("TTY")
else:
    print("NOT")
EOF
$ chmod +x .git/hooks/applypatch-msg

$ git checkout -b temp origin/master^
$ git format-patch master -1

# With git 2.6
$ git am 0001-Git-2.6.patch
NOT
Applying: Git 2.6

# With git 2.5.3
TTY
Applying: Git 2.6

Thanks,
Chris