[PATCH 0 of 1] merge: add --no-fast-forward to suppress fast-forward merge

[FUJIWARA Katsunori]

The behavior of Mercurial on merge between named branches is changed
to 'fast-forward' style since 1.8 by 9e7e24052745.

There is quite a few people who requires 'old'(= not fast-forward)
style merge, but there is no way to choose 'old' style on merge.

So, I tried to implement experimental patch to add '--no-fast-forward'
option.

This patch is just implemented for base of discussion: no enough
coverage, not well tested :-)

  - is there few people who requires such 'old' style merge ?

  - which should default behavior of merge be fast-forward or not ?

  - does my patch have enough coverage ?

      I have just checked (directly/in-directly) invocations of
      merge()@hg.py and update()@merge.py in mercurial core and hgext.

  - are there any other good solutions ?

  - and so on....

Please comment on !


BTW, I cannot find out any documentation about introducing of
fast-forward merge in 1.8 release artifacts. Does this confuse
existing users ?