precommit mercurial hook to stop commits to the wrong branch

[Faheem Mitha]

On Thu, 10 Oct 2013, Faheem Mitha wrote:

> I see there is also http://mercurial.selenic.com/wiki/PythonHglib

I posted the following approach to SO:

http://stackoverflow.com/a/19305079/350713

The post appears below. However, I still have a problem.

I use mq, and when it comes to mq commits, I don't care what commits are 
made to what branch, because mq itself doesn't really care about branches 
(an mq patch takes the name of whatever branch it is qpushed to), and so 
one can merrily pop and push mq patches between branches.

So, is there some good way to tell the hook that if the commit in progress 
is an mq commit, don't do anything?

I looked at mq.py for a bit, but didn't see any obvious way to do this. As 
you can see, I am using hglib for my hook, so a solution that integrates 
with hglib would be nice, but if I have to drop down to a low level API, 
then I guess I can live with that.

                                                            Regards, Faheem

########################################################################

Using @Ry4an's solution as a starting point, I came up with the following 
script using the new hglib API.

#!/usr/bin/python

# Abort commit to the debian branch if it is not contained in a debian
# subdirectory

# Similary abort commit to non-debian branches if it is contained in a
# debian subdirectory

import hglib, os, sys
client = hglib.open("/home/faheem/hooktest")
ctx = client['tip']
files = ctx.files()
branch = ctx.branch()

for f in files:
     d = os.path.dirname(f)
     if branch == "debian" and d != "debian":
         sys.exit("cannot commit %s (file not in 'debian' directory) to 
'debian' branch"%f)
     if branch != "debian" and d == "debian":
         sys.exit("cannot commit %s (file in 'debian' directory) to non 
'debian' branch"%f)