Pull request workflow - changes post review and multiple heads

[Jaikiran Pai]

Hello everyone,

We have a workflow within our team which is as follows:

- There's an "upstream" repo "foo" which is shared by the team. Only 
select members have push access to it
- There are N developers in the team, each one working against a forked 
copy of the upstream repo, under their own account.
- Each of them commit to their own repos and issue a pull request once 
they have their feature/bug-fix ready for review.
- A reviewer goes through the commit "A" in the pull request and 
suggests any changes that are needed
- The developer then fixes those issues in the pull request and adds a 
new commit "B" to the pull request.

What we ideally want to do is "fold" A and B into one commit and have it 
pushed to the "upstream". It's straightforward to ask the developer to 
fold those 2 commits and *force* push the changesets to this own repo 
(which by the way isn't shared). The force push is needed since the fold 
ends up creating a new head. Of course, the (redundant) head can then be 
manually closed via a "hg commit --close-branch" but is there a better 
way of dealing with this? Perhaps auto-closing the redundant head while 
dealing with the fold?

The end goal we are trying to achieve is having the commits from most of 
the developers come through via pull requests and once the changes are 
reviewed and approved, have them committed as one (in most cases) 
logical commits.

-Jaikiran