A new flag --aggressive resolves what we traditionally resolved
with external git-merge-one-file inside index while read-tree
3-way merge works.
git-merge-octopus and git-merge-resolve use this flag before
running git-merge-index with git-merge-one-file.
Signed-off-by: Junio C Hamano <junkio@cox.net>
We rejected multi-base merge situations even though we used the
same underlying multi-base git-read-tree as the resolve strategy
uses. This was unneeded and did not add much to ensure the
merge to be truly trivial, so remove this restriction and be
more similar to what resolve does.
Also when the merge did not trivially resolve, we rejected
without stating that octopus strategy does not handle the
situation.
Signed-off-by: Junio C Hamano <junkio@cox.net>
As a fallout from not using git-sh-setup in scripts that can
operate from a subdirectory, we lost definition of die() from
them. It might make sense to do some cleanup to consolidate
them back again, but this should suffice for now.
Signed-off-by: Junio C Hamano <junkio@cox.net>
When doing an octopus, we incorrectly used the previous merge
base as the reference to compute next merge base. This was
unnecessary, because that can never be better than using the
original HEAD. And that is far simpler as well ;-).
Signed-off-by: Junio C Hamano <junkio@cox.net>
The new command 'git merge' takes the current head and one or more
remote heads, with the commit log message for the automated case.
If the heads being merged are simple fast-forwards, it acts the
same way as the current 'git resolve'. Otherwise, it tries
different merge strategies and takes the result from the one that
succeeded auto-merging, if there is any.
If no merge strategy succeeds auto-merging, their results are
evaluated for number of paths needed for hand resolving, and the
one with the least number of such paths is left in the working
tree. The user is asked to resolve them by hand and make a
commit manually.
The calling convention from the 'git merge' driver to merge
strategy programs is very simple:
- A strategy program is to be called 'git-merge-<strategy>'.
- They take input of this form:
<common1> <common2> ... '--' <head> <remote1> <remote2>...
That is, one or more the common ancestors, double dash, the
current head, and one or more remote heads being merged into
the current branch.
- Before a strategy program is called, the working tree is
matched to the current <head>.
- The strategy program exits with status code 0 when it
successfully auto-merges the given heads. It should do
update-cache for all the merged paths when it does so -- the
index file will be used to record the merge result as a
commit by the driver.
- The strategy program exits with status code 1 when it leaves
conflicts behind. It should do update-cache for all the
merged paths that it successfully auto-merged, and leave the
cache entry in the index file as the same as <head> for paths
it could not auto-merge, and leave its best-effort result
with conflict markers in the working tree when it does so.
- The strategy program exists with status code other than 0 or
1 if it does not handle the given merge at all.
As examples, this commit comes with merge strategies based on
'git resolve' and 'git octopus'.
Signed-off-by: Junio C Hamano <junkio@cox.net>
