"git merge-base --octopus" used to leave cleaning up suboptimal
result to the caller, but now it does the clean-up itself.
* bm/merge-base-octopus-dedup:
merge-base --octopus: reduce the result from get_octopus_merge_bases()
merge-base: separate "--independent" codepath into its own helper
Scripts that use "merge-base --octopus" could do the reducing
themselves, but most of them are expected to want to get the reduced
results without having to do any work themselves.
Tests are taken from a message by Василий Макаров
<einmalfel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
We might want to vet the existing callers of the underlying
get_octopus_merge_bases() and find out if _all_ of them are doing
anything extra (like deduping) because the machinery can return
duplicate results. And if that is the case, then we may want to
move the dedupling down the callchain instead of having it here.
It piggybacks on an unrelated handle_octopus() function only because
there are some similarities between the way they need to preprocess
their input and output their result. There is nothing similar in
the true logic between these two operations.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "git pull --rebase" command computes the fork point of the
branch being rebased using the reflog entries of the "base" branch
(typically a remote-tracking branch) the branch's work was based on,
in order to cope with the case in which the "base" branch has been
rewound and rebuilt. For example, if the history looked like this:
o---B1
/
---o---o---B2--o---o---o---Base
\
B3
\
Derived
where the current tip of the "base" branch is at Base, but earlier
fetch observed that its tip used to be B3 and then B2 and then B1
before getting to the current commit, and the branch being rebased
on top of the latest "base" is based on commit B3, it tries to find
B3 by going through the output of "git rev-list --reflog base" (i.e.
Base, B1, B2, B3) until it finds a commit that is an ancestor of the
current tip "Derived".
Internally, we have get_merge_bases_many() that can compute this
with one-go. We would want a merge-base between Derived and a
fictitious merge commit that would result by merging all the
historical tips of "base". When such a commit exist, we should get
a single result, which exactly match one of the reflog entries of
"base".
Teach "git merge-base" a new mode, "--fork-point", to compute
exactly that.
Helped-by: Martin von Zweigbergk <martinvonz@gmail.com>
Helped-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The --octopus, --independent and --is-ancestor are mutually
exclusive command modes (in addition to not giving any of these
options), so represent them as such using the recent OPT_CMDMODE
facility available since 11588263 (parse-options: add OPT_CMDMODE(),
2013-07-30), which is in v1.8.4-82-g366b80b. --all is compatible
only with plain vanilla mode and --octopus mode, and the minimum
number of arguments the command takes depends on the command modes,
so these are now separately checked in each command mode.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This task emerged from b04ba2bb (parse-options: deprecate OPT_BOOLEAN,
2011-09-27). All occurrences of the respective variables have
been reviewed and none of them relied on the counting up mechanism,
but all of them were using the variable as a true boolean.
This patch does not change semantics of any command intentionally.
Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The compiler can short-circuit the evaluation of conditions strung
together with logical OR operators instead of computing the resulting
bitmask with binary ORs. More importantly, this patch makes the
intent of the changed code clearer, because the logical context (as
opposed to binary context) becomes immediately obvious.
While we're at it, simplify the check for patch->is_rename in
builtin/apply.c a bit; it can only be 0 or 1, so we don't need a
comparison operator.
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Optimise the "merge-base" computation a bit, and also update its
users that do not need the full merge-base information to call a
cheaper subset.
* jc/merge-bases:
reduce_heads(): reimplement on top of remove_redundant()
merge-base: "--is-ancestor A B"
get_merge_bases_many(): walk from many tips in parallel
in_merge_bases(): use paint_down_to_common()
merge_bases_many(): split out the logic to paint history
in_merge_bases(): omit unnecessary redundant common ancestor reduction
http-push: use in_merge_bases() for fast-forward check
receive-pack: use in_merge_bases() for fast-forward check
in_merge_bases(): support only one "other" commit
In many scripted Porcelain commands, we find this idiom:
if test "$(git rev-parse --verify A)" = "$(git merge-base A B)"
then
... A is an ancestor of B ...
fi
But you do not have to compute exact merge-base only to see if A is
an ancestor of B. Give them a more direct way to use the underlying
machinery.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unlike plain merge-base, merge-base --octopus only requires at least one
commit argument; update the synopsis to reflect that.
Add a sentence to the discussion that when --octopus is used, we do expect
'2' (the common ansestor across all) as the result.
Signed-off-by: Vincent van Ravesteijn <vfr@lyx.org>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While show-branch --independent does not support more than MAX_REVS
revs, git internally supports more with a different algorithm.
Expose that functionality as "git merge-base --independent".
This should help scripts to catch up with builtin merge in supporting
dodecapus.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While show-branch --merge-base does not support more than MAX_REVS
revs, git supports more with a different algorithm
(v1.6.0-rc0~51^2~13, Introduce get_octopus_merge_bases() in commit.c,
2008-06-27). Expose that functionality.
This should help scripts to catch up with builtin merge in supporting
dodecapus.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This shrinks the top-level directory a bit, and makes it much more
pleasant to use auto-completion on the thing. Instead of
[torvalds@nehalem git]$ em buil<tab>
Display all 180 possibilities? (y or n)
[torvalds@nehalem git]$ em builtin-sh
builtin-shortlog.c builtin-show-branch.c builtin-show-ref.c
builtin-shortlog.o builtin-show-branch.o builtin-show-ref.o
[torvalds@nehalem git]$ em builtin-shor<tab>
builtin-shortlog.c builtin-shortlog.o
[torvalds@nehalem git]$ em builtin-shortlog.c
you get
[torvalds@nehalem git]$ em buil<tab> [type]
builtin/ builtin.h
[torvalds@nehalem git]$ em builtin [auto-completes to]
[torvalds@nehalem git]$ em builtin/sh<tab> [type]
shortlog.c shortlog.o show-branch.c show-branch.o show-ref.c show-ref.o
[torvalds@nehalem git]$ em builtin/sho [auto-completes to]
[torvalds@nehalem git]$ em builtin/shor<tab> [type]
shortlog.c shortlog.o
[torvalds@nehalem git]$ em builtin/shortlog.c
which doesn't seem all that different, but not having that annoying
break in "Display all 180 possibilities?" is quite a relief.
NOTE! If you do this in a clean tree (no object files etc), or using an
editor that has auto-completion rules that ignores '*.o' files, you
won't see that annoying 'Display all 180 possibilities?' message - it
will just show the choices instead. I think bash has some cut-off
around 100 choices or something.
So the reason I see this is that I'm using an odd editory, and thus
don't have the rules to cut down on auto-completion. But you can
simulate that by using 'ls' instead, or something similar.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
