3 # Copyright (c) 2005 Junio C Hamano
8 git merge [options] <remote>...
9 git merge [options] <msg> HEAD <remote>
11 stat show a diffstat at the end of the merge
12 n don't show a diffstat at the end of the merge
13 summary (synonym to --stat)
14 log add list of one-line log to merge commit message
15 squash create a single commit instead of doing a merge
16 commit perform a commit if the merge succeeds (default)
17 ff allow fast-forward (default)
18 s,strategy= merge strategy to use
19 m,message= message to be used for the merge commit (if any)
27 test -z "$(git ls-files -u)" ||
28 die
"Merge is not possible because you have unmerged files."
30 ! test -e "$GIT_DIR/MERGE_HEAD" ||
31 die
'You have not concluded your merge (MERGE_HEAD exists).'
36 all_strategies
='recur recursive octopus resolve stupid ours subtree'
37 all_strategies
="$all_strategies recursive-ours recursive-theirs"
38 default_twohead_strategies
='recursive'
39 default_octopus_strategies
='octopus'
40 no_fast_forward_strategies
='subtree ours'
41 no_trivial_strategies
='recursive recur subtree ours recursive-ours recursive-theirs'
46 squash
= no_commit
= log_arg
=
49 rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \
50 "$GIT_DIR/MERGE_STASH" ||
exit 1
54 # Stash away any local modifications.
55 git stash create
>"$GIT_DIR/MERGE_STASH"
59 if test -f "$GIT_DIR/MERGE_STASH"
61 git
reset --hard $head >/dev
/null
62 git stash apply $
(cat "$GIT_DIR/MERGE_STASH")
63 git update-index
--refresh >/dev
/null
67 finish_up_to_date
() {
70 echo "$1 (nothing to squash)" ;;
78 echo Squashed commit of the following
:
80 git log
--no-merges --pretty=medium ^
"$head" $remoteheads
86 rlogm
="$GIT_REFLOG_ACTION"
89 rlogm
="$GIT_REFLOG_ACTION: $2"
93 echo "Squash commit -- not updating HEAD"
94 squash_message
>"$GIT_DIR/SQUASH_MSG"
99 echo "No merge message -- not updating HEAD"
102 git update-ref
-m "$rlogm" HEAD
"$1" "$head" ||
exit 1
112 if test "$show_diffstat" = t
114 # We want color (if set), but no pager
115 GIT_PAGER
='' git
diff --stat --summary -M "$head" "$1"
120 # Run a post-merge hook
121 if test -x "$GIT_DIR"/hooks
/post-merge
125 "$GIT_DIR"/hooks
/post-merge
1
128 "$GIT_DIR"/hooks
/post-merge
0
136 rh
=$
(git rev-parse
--verify "$remote^0" 2>/dev
/null
) ||
return
137 bh
=$
(git show-ref
-s --verify "refs/heads/$remote" 2>/dev
/null
)
138 if test "$rh" = "$bh"
140 echo "$rh branch '$remote' of ."
141 elif truname
=$
(expr "$remote" : '\(.*\)~[1-9][0-9]*$') &&
142 git show-ref
-q --verify "refs/heads/$truname" 2>/dev
/null
144 echo "$rh branch '$truname' (early part) of ."
145 elif test "$remote" = "FETCH_HEAD" -a -r "$GIT_DIR/FETCH_HEAD"
147 sed -e 's/ not-for-merge / /' -e 1q \
148 "$GIT_DIR/FETCH_HEAD"
150 echo "$rh commit '$remote'"
155 while test $# != 0; do
157 -n|
--no-stat|
--no-summary)
158 show_diffstat
=false
;;
164 test "$allow_fast_forward" = t ||
165 die
"You cannot combine --squash with --no-ff."
166 squash
=t no_commit
=t
;;
168 squash
= no_commit
= ;;
174 allow_fast_forward
=t
;;
176 test "$squash" != t ||
177 die
"You cannot combine --squash with --no-ff."
178 allow_fast_forward
=f
;;
181 case " $all_strategies " in
183 use_strategies
="$use_strategies$1 " ;;
185 die
"available strategies are: $all_strategies" ;;
203 test $# != 0 || usage
207 if branch
=$
(git-symbolic-ref
-q HEAD
)
209 mergeopts
=$
(git config
"branch.${branch#refs/heads/}.mergeoptions")
210 if test -n "$mergeopts"
212 parse_config
$mergeopts --
217 while test $args_left -lt $#; do shift; done
219 if test -z "$show_diffstat"; then
220 test "$(git config --bool merge.diffstat)" = false
&& show_diffstat
=false
221 test "$(git config --bool merge.stat)" = false
&& show_diffstat
=false
222 test -z "$show_diffstat" && show_diffstat
=t
225 # This could be traditional "merge <msg> HEAD <commit>..." and the
226 # way we can tell it is to see if the second token is HEAD, but some
227 # people might have misused the interface and used a committish that
228 # is the same as HEAD there instead. Traditional format never would
229 # have "-m" so it is an additional safety measure to check for it.
231 if test -z "$have_message" &&
232 second_token
=$
(git rev-parse
--verify "$2^0" 2>/dev
/null
) &&
233 head_commit
=$
(git rev-parse
--verify "HEAD" 2>/dev
/null
) &&
234 test "$second_token" = "$head_commit"
240 elif ! git rev-parse
--verify HEAD
>/dev
/null
2>&1
242 # If the merged head is a valid one there is no reason to
243 # forbid "git merge" into a branch yet to be born. We do
244 # the same for "git pull".
247 echo >&2 "Can merge only exactly one commit into empty head"
251 test "$squash" != t ||
252 die
"Squash commit into empty head not supported yet"
253 test "$allow_fast_forward" = t ||
254 die
"Non-fast-forward into an empty head does not make sense"
255 rh
=$
(git rev-parse
--verify "$1^0") ||
256 die
"$1 - not something we can merge"
258 git update-ref
-m "initial pull" HEAD
"$rh" "" &&
259 git read-tree
--reset -u HEAD
263 # We are invoked directly as the first-class UI.
266 # All the rest are the commits being merged; prepare
267 # the standard merge summary message to be appended to
268 # the given message. If remote is invalid we will die
269 # later in the common codepath so we discard the error
271 merge_name
=$
(for remote
274 done | git fmt-merge-msg
$log_arg
276 merge_msg
="${merge_msg:+$merge_msg$LF$LF}$merge_name"
278 head=$
(git rev-parse
--verify "$head_arg"^
0) || usage
280 # All the rest are remote heads
281 test "$#" = 0 && usage
;# we need at least one remote head.
282 set_reflog_action
"merge $*"
287 remotehead
=$
(git rev-parse
--verify "$remote"^
0 2>/dev
/null
) ||
288 die
"$remote - not something we can merge"
289 remoteheads
="${remoteheads}$remotehead "
290 eval GITHEAD_
$remotehead='"$remote"'
291 export GITHEAD_
$remotehead
293 set x
$remoteheads ; shift
295 case "$use_strategies" in
299 var
="`git config --get pull.twohead`"
302 use_strategies
="$var"
304 use_strategies
="$default_twohead_strategies"
307 var
="`git config --get pull.octopus`"
310 use_strategies
="$var"
312 use_strategies
="$default_octopus_strategies"
318 for s
in $use_strategies
320 for ss
in $no_fast_forward_strategies
329 for ss
in $no_trivial_strategies
333 allow_trivial_merge
=f
342 common
=$
(git merge-base
--all $head "$@")
345 common
=$
(git show-branch
--merge-base $head "$@")
348 echo "$head" >"$GIT_DIR/ORIG_HEAD"
350 case "$allow_fast_forward,$#,$common,$no_commit" in
352 # No common ancestors found. We need a real merge.
355 # If head can reach all the merge then we are up to date.
356 # but first the most common case of merging one remote.
357 finish_up_to_date
"Already up-to-date."
361 # Again the most common case of merging one remote.
362 echo "Updating $(git rev-parse --short $head)..$(git rev-parse --short $1)"
363 git update-index
--refresh 2>/dev
/null
365 if test -n "$have_message"
367 msg
="$msg (no commit created; -m option ignored)"
369 new_head
=$
(git rev-parse
--verify "$1^0") &&
370 git read-tree
-v -m -u --exclude-per-directory=.gitignore
$head "$new_head" &&
371 finish
"$new_head" "$msg" ||
exit
376 # We are not doing octopus and not fast-forward. Need a
380 # We are not doing octopus, not fast-forward, and have only
382 git update-index
--refresh 2>/dev
/null
383 case "$allow_trivial_merge" in
385 # See if it is really trivial.
386 git var GIT_COMMITTER_IDENT
>/dev
/null ||
exit
387 echo "Trying really trivial in-index merge..."
388 if git read-tree
--trivial -m -u -v $common $head "$1" &&
389 result_tree
=$
(git write-tree
)
393 printf '%s\n' "$merge_msg" |
394 git commit-tree
$result_tree -p HEAD
-p "$1"
396 finish
"$result_commit" "In-index merge"
404 # An octopus. If we can reach all the remote we are up to date.
408 common_one
=$
(git merge-base
--all $head $remote)
409 if test "$common_one" != "$remote"
415 if test "$up_to_date" = t
417 finish_up_to_date
"Already up-to-date. Yeeah!"
423 # We are going to make a new commit.
424 git var GIT_COMMITTER_IDENT
>/dev
/null ||
exit
426 # At this point, we need a real merge. No matter what strategy
427 # we use, it would operate on the index, possibly affecting the
428 # working tree, and when resolved cleanly, have the desired tree
429 # in the index -- this means that the index must be in sync with
430 # the $head commit. The strategies are responsible to ensure this.
432 case "$use_strategies" in
434 # Stash away the local changes so that we can try more than one.
439 rm -f "$GIT_DIR/MERGE_STASH"
444 result_tree
= best_cnt
=-1 best_strategy
= wt_strategy
=
446 for strategy
in $use_strategies
448 test "$wt_strategy" = '' ||
{
449 echo "Rewinding the tree to pristine..."
452 case "$single_strategy" in
454 echo "Trying merge strategy $strategy..."
458 # Remember which strategy left the state in the working tree
459 wt_strategy
=$strategy
461 git-merge-
$strategy $common -- "$head_arg" "$@"
463 if test "$no_commit" = t
&& test "$exit" = 0
466 exit=1 ;# pretend it left conflicts.
469 test "$exit" = 0 ||
{
471 # The backend exits with 1 when conflicts are left to be resolved,
472 # with 2 when it does not handle the given merge at all.
474 if test "$exit" -eq 1
477 git diff-files --name-only
478 git ls-files --unmerged
480 if test $best_cnt -le 0 -o $cnt -le $best_cnt
482 best_strategy
=$strategy
489 # Automerge succeeded.
490 result_tree
=$
(git write-tree
) && break
493 # If we have a resulting tree, that means the strategy module
494 # auto resolved the merge cleanly.
495 if test '' != "$result_tree"
497 if test "$allow_fast_forward" = "t"
499 parents
=$
(git show-branch
--independent "$head" "$@")
501 parents
=$
(git rev-parse
"$head" "$@")
503 parents
=$
(echo "$parents" |
sed -e 's/^/-p /')
504 result_commit
=$
(printf '%s\n' "$merge_msg" | git commit-tree
$result_tree $parents) ||
exit
505 finish
"$result_commit" "Merge made by $wt_strategy."
510 # Pick the result from the best strategy and have the user fix it up.
511 case "$best_strategy" in
514 case "$use_strategies" in
516 echo >&2 "No merge strategy handled the merge."
519 echo >&2 "Merge with strategy $use_strategies failed."
525 # We already have its result in the working tree.
528 echo "Rewinding the tree to pristine..."
530 echo "Using the $best_strategy to prepare resolving by hand."
531 git-merge-
$best_strategy $common -- "$head_arg" "$@"
535 if test "$squash" = t
542 done >"$GIT_DIR/MERGE_HEAD"
543 printf '%s\n' "$merge_msg" >"$GIT_DIR/MERGE_MSG"
546 if test "$merge_was_ok" = t
549 "Automatic merge went well; stopped before committing as requested"
556 git ls-files
--unmerged |
557 sed -e 's/^[^ ]* / /' |
559 } >>"$GIT_DIR/MERGE_MSG"
561 die
"Automatic merge failed; fix conflicts and then commit the result."