precommit mercurial hook to stop commits to the wrong branch

[Faheem Mitha]

Hi Mads,

Thanks for the comments.

On Wed, 9 Oct 2013, Mads Kiilerich wrote:

> On 10/09/2013 11:09 AM, Faheem Mitha wrote:
>> Ry4an kindly replied with a bash solution. I think I would prefer a Python 
>> version, but that would use the Mercurial "not-an-api", as Ry4an put it. 
>> Does this look practical? If anyone feels like taking the time to sketch an 
>> approach, I'd appreciate it. Regardless, any comments would be appreciated, 
>> Thanks.
>
> You mention the reasons that a small script probably is the best solution. It 
> could be implemented in python but be launched as a separate command without 
> using the internal API.

> That is not perfect but that is how it is.

I'm not sure what you have in mind when you say "implemented in python but 
be launched as a separate command without using the internal API".

In any case, I'd still like to use the API, as documented for example by 
http://mercurial.selenic.com/wiki/MercurialApi

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

Is this perhaps what you meant? The description says

"hgapi is a pure-Python API to Mercurial, that uses the command-line 
interface instead of the internal Mercurial API. The rationale for this 
is twofold: the internal API is unstable, and it is GPL."

This python-hglib seems to have just arrived in Debian - it is in testing 
and unstable but not in stable.

so maybe this is a best-of-both-worlds kind of thing. I guess I could try 
these two alternatives (internal API and hglib).

                                                           Regards, Faheem

> However, a development idea / "feature request":

> Introduce a new hook type that takes a revset in the hook configuration. 
> Perhaps with different variants/configurations for rejecting when either 
> none, any or all revisions is matching. Perhaps also with a template for 
> which message should be shown to the user.
>
> This would essentially be very much like something like
>  myhook = ! ( hg log -r "..." --template "...\n" | grep . )
> but cross platform and more efficient and very easy to configure.
>
> My gut feeling is that it would be so generic and useful that it would have a 
> good chance of getting accepted upstream.

> /Mads