D210: pushvars: move fb extension pushvars to core

[durin42 (Augie Fackler)]

durin42 added a comment.


  I've often wanted a way to have extra arguments to push commands (etc), but I'm not sure that just exporting all environment variables is exactly the interface I want. Could we accomplish something similar by having an --extra-args= flag that delivers a part with an arbitrary payload that can then be used (or not) by hooks as they see fit? Or is that too challenging?
  
  (The environment variable model also feels like it fits poorly with http servers, in my brain.)

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D210

To: pulkit, #hg-reviewers
Cc: durin42, akushner, mercurial-devel