#!/bin/sh # # Copyright (c) 2005 Junio C Hamano # OPTIONS_KEEPDASHDASH= OPTIONS_SPEC="\ git merge [options] <remote>... git merge [options] <msg> HEAD <remote> -- stat show a diffstat at the end of the merge n don't show a diffstat at the end of the merge summary (synonym to --stat) log add list of one-line log to merge commit message squash create a single commit instead of doing a merge commit perform a commit if the merge succeeds (default) ff allow fast-forward (default) ff-only abort if fast-forward is not possible rerere-autoupdate update index with any reused conflict resolution s,strategy= merge strategy to use X= option for selected merge strategy m,message= message to be used for the merge commit (if any) " SUBDIRECTORY_OK=Yes . git-sh-setup require_work_tree cd_to_toplevel test -z "$(git ls-files -u)" || die "Merge is not possible because you have unmerged files." ! test -e "$GIT_DIR/MERGE_HEAD" || die 'You have not concluded your merge (MERGE_HEAD exists).' LF=' ' all_strategies='recur recursive octopus resolve stupid ours subtree' all_strategies="$all_strategies recursive-ours recursive-theirs" not_strategies='base file index tree' default_twohead_strategies='recursive' default_octopus_strategies='octopus' no_fast_forward_strategies='subtree ours' no_trivial_strategies='recursive recur subtree ours recursive-ours recursive-theirs' use_strategies= xopt= allow_fast_forward=t fast_forward_only= allow_trivial_merge=t squash= no_commit= log_arg= rr_arg= dropsave() { rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \ "$GIT_DIR/MERGE_STASH" "$GIT_DIR/MERGE_MODE" || exit 1 } savestate() { # Stash away any local modifications. git stash create >"$GIT_DIR/MERGE_STASH" } restorestate() { if test -f "$GIT_DIR/MERGE_STASH" then git reset --hard $head >/dev/null git stash apply $(cat "$GIT_DIR/MERGE_STASH") git update-index --refresh >/dev/null fi } finish_up_to_date () { case "$squash" in t) echo "$1 (nothing to squash)" ;; '') echo "$1" ;; esac dropsave } squash_message () { echo Squashed commit of the following: echo git log --no-merges --pretty=medium ^"$head" $remoteheads } finish () { if test '' = "$2" then rlogm="$GIT_REFLOG_ACTION" else echo "$2" rlogm="$GIT_REFLOG_ACTION: $2" fi case "$squash" in t) echo "Squash commit -- not updating HEAD" squash_message >"$GIT_DIR/SQUASH_MSG" ;; '') case "$merge_msg" in '') echo "No merge message -- not updating HEAD" ;; *) git update-ref -m "$rlogm" HEAD "$1" "$head" || exit 1 git gc --auto ;; esac ;; esac case "$1" in '') ;; ?*) if test "$show_diffstat" = t then # We want color (if set), but no pager GIT_PAGER='' git diff --stat --summary -M "$head" "$1" fi ;; esac # Run a post-merge hook if test -x "$GIT_DIR"/hooks/post-merge then case "$squash" in t) "$GIT_DIR"/hooks/post-merge 1 ;; '') "$GIT_DIR"/hooks/post-merge 0 ;; esac fi } merge_name () { remote="$1" rh=$(git rev-parse --verify "$remote^0" 2>/dev/null) || return if truname=$(expr "$remote" : '\(.*\)~[0-9]*$') && git show-ref -q --verify "refs/heads/$truname" 2>/dev/null then echo "$rh branch '$truname' (early part) of ." return fi if found_ref=$(git rev-parse --symbolic-full-name --verify \ "$remote" 2>/dev/null) then expanded=$(git check-ref-format --branch "$remote") || exit if test "${found_ref#refs/heads/}" != "$found_ref" then echo "$rh branch '$expanded' of ." return elif test "${found_ref#refs/remotes/}" != "$found_ref" then echo "$rh remote branch '$expanded' of ." return fi fi if test "$remote" = "FETCH_HEAD" && test -r "$GIT_DIR/FETCH_HEAD" then sed -e 's/ not-for-merge / /' -e 1q \ "$GIT_DIR/FETCH_HEAD" return fi echo "$rh commit '$remote'" } parse_config () { while test $# != 0; do case "$1" in -n|--no-stat|--no-summary) show_diffstat=false ;; --stat|--summary) show_diffstat=t ;; --log|--no-log) log_arg=$1 ;; --squash) test "$allow_fast_forward" = t || die "You cannot combine --squash with --no-ff." squash=t no_commit=t ;; --no-squash) squash= no_commit= ;; --commit) no_commit= ;; --no-commit) no_commit=t ;; --ff) allow_fast_forward=t ;; --no-ff) test "$squash" != t || die "You cannot combine --squash with --no-ff." test "$fast_forward_only" != t || die "You cannot combine --ff-only with --no-ff." allow_fast_forward=f ;; --ff-only) test "$allow_fast_forward" != f || die "You cannot combine --ff-only with --no-ff." fast_forward_only=t ;; --rerere-autoupdate|--no-rerere-autoupdate) rr_arg=$1 ;; -s|--strategy) shift case " $all_strategies " in *" $1 "*) use_strategies="$use_strategies$1 " ;; *) case " $not_strategies " in *" $1 "*) false esac && type "git-merge-$1" >/dev/null 2>&1 || die "available strategies are: $all_strategies" use_strategies="$use_strategies$1 " ;; esac ;; -X) shift xopt="${xopt:+$xopt }$(git rev-parse --sq-quote "--$1")" ;; -m|--message) shift merge_msg="$1" have_message=t ;; --) shift break ;; *) usage ;; esac shift done args_left=$# } test $# != 0 || usage have_message= if branch=$(git-symbolic-ref -q HEAD) then mergeopts=$(git config "branch.${branch#refs/heads/}.mergeoptions") if test -n "$mergeopts" then parse_config $mergeopts -- fi fi parse_config "$@" while test $args_left -lt $#; do shift; done if test -z "$show_diffstat"; then test "$(git config --bool merge.diffstat)" = false && show_diffstat=false test "$(git config --bool merge.stat)" = false && show_diffstat=false test -z "$show_diffstat" && show_diffstat=t fi # This could be traditional "merge <msg> HEAD <commit>..." and the # way we can tell it is to see if the second token is HEAD, but some # people might have misused the interface and used a commit-ish that # is the same as HEAD there instead. Traditional format never would # have "-m" so it is an additional safety measure to check for it. if test -z "$have_message" && second_token=$(git rev-parse --verify "$2^0" 2>/dev/null) && head_commit=$(git rev-parse --verify "HEAD" 2>/dev/null) && test "$second_token" = "$head_commit" then merge_msg="$1" shift head_arg="$1" shift elif ! git rev-parse --verify HEAD >/dev/null 2>&1 then # If the merged head is a valid one there is no reason to # forbid "git merge" into a branch yet to be born. We do # the same for "git pull". if test 1 -ne $# then echo >&2 "Can merge only exactly one commit into empty head" exit 1 fi test "$squash" != t || die "Squash commit into empty head not supported yet" test "$allow_fast_forward" = t || die "Non-fast-forward into an empty head does not make sense" rh=$(git rev-parse --verify "$1^0") || die "$1 - not something we can merge" git update-ref -m "initial pull" HEAD "$rh" "" && git read-tree --reset -u HEAD exit else # We are invoked directly as the first-class UI. head_arg=HEAD # All the rest are the commits being merged; prepare # the standard merge summary message to be appended to # the given message. If remote is invalid we will die # later in the common codepath so we discard the error # in this loop. merge_msg="$( for remote do merge_name "$remote" done | if test "$have_message" = t then git fmt-merge-msg -m "$merge_msg" $log_arg else git fmt-merge-msg $log_arg fi )" fi head=$(git rev-parse --verify "$head_arg"^0) || usage # All the rest are remote heads test "$#" = 0 && usage ;# we need at least one remote head. set_reflog_action "merge $*" remoteheads= for remote do remotehead=$(git rev-parse --verify "$remote"^0 2>/dev/null) || die "$remote - not something we can merge" remoteheads="${remoteheads}$remotehead " eval GITHEAD_$remotehead='"$remote"' export GITHEAD_$remotehead done set x $remoteheads ; shift case "$use_strategies" in '') case "$#" in 1) var="$(git config --get pull.twohead)" if test -n "$var" then use_strategies="$var" else use_strategies="$default_twohead_strategies" fi ;; *) var="$(git config --get pull.octopus)" if test -n "$var" then use_strategies="$var" else use_strategies="$default_octopus_strategies" fi ;; esac ;; esac for s in $use_strategies do for ss in $no_fast_forward_strategies do case " $s " in *" $ss "*) allow_fast_forward=f break ;; esac done for ss in $no_trivial_strategies do case " $s " in *" $ss "*) allow_trivial_merge=f break ;; esac done done case "$#" in 1) common=$(git merge-base --all $head "$@") ;; *) common=$(git merge-base --all --octopus $head "$@") ;; esac echo "$head" >"$GIT_DIR/ORIG_HEAD" case "$allow_fast_forward,$#,$common,$no_commit" in ?,*,'',*) # No common ancestors found. We need a real merge. ;; ?,1,"$1",*) # If head can reach all the merge then we are up to date. # but first the most common case of merging one remote. finish_up_to_date "Already up-to-date." exit 0 ;; t,1,"$head",*) # Again the most common case of merging one remote. echo "Updating $(git rev-parse --short $head)..$(git rev-parse --short $1)" git update-index --refresh 2>/dev/null msg="Fast-forward" if test -n "$have_message" then msg="$msg (no commit created; -m option ignored)" fi new_head=$(git rev-parse --verify "$1^0") && git read-tree -v -m -u --exclude-per-directory=.gitignore $head "$new_head" && finish "$new_head" "$msg" || exit dropsave exit 0 ;; ?,1,?*"$LF"?*,*) # We are not doing octopus and not fast-forward. Need a # real merge. ;; ?,1,*,) # We are not doing octopus, not fast-forward, and have only # one common. git update-index --refresh 2>/dev/null case "$allow_trivial_merge,$fast_forward_only" in t,) # See if it is really trivial. git var GIT_COMMITTER_IDENT >/dev/null || exit echo "Trying really trivial in-index merge..." if git read-tree --trivial -m -u -v $common $head "$1" && result_tree=$(git write-tree) then echo "Wonderful." result_commit=$( printf '%s\n' "$merge_msg" | git commit-tree $result_tree -p HEAD -p "$1" ) || exit finish "$result_commit" "In-index merge" dropsave exit 0 fi echo "Nope." esac ;; *) # An octopus. If we can reach all the remote we are up to date. up_to_date=t for remote do common_one=$(git merge-base --all $head $remote) if test "$common_one" != "$remote" then up_to_date=f break fi done if test "$up_to_date" = t then finish_up_to_date "Already up-to-date. Yeeah!" exit 0 fi ;; esac if test "$fast_forward_only" = t then die "Not possible to fast-forward, aborting." fi # We are going to make a new commit. git var GIT_COMMITTER_IDENT >/dev/null || exit # At this point, we need a real merge. No matter what strategy # we use, it would operate on the index, possibly affecting the # working tree, and when resolved cleanly, have the desired tree # in the index -- this means that the index must be in sync with # the $head commit. The strategies are responsible to ensure this. case "$use_strategies" in ?*' '?*) # Stash away the local changes so that we can try more than one. savestate single_strategy=no ;; *) rm -f "$GIT_DIR/MERGE_STASH" single_strategy=yes ;; esac result_tree= best_cnt=-1 best_strategy= wt_strategy= merge_was_ok= for strategy in $use_strategies do test "$wt_strategy" = '' || { echo "Rewinding the tree to pristine..." restorestate } case "$single_strategy" in no) echo "Trying merge strategy $strategy..." ;; esac # Remember which strategy left the state in the working tree wt_strategy=$strategy eval 'git-merge-$strategy '"$xopt"' $common -- "$head_arg" "$@"' exit=$? if test "$no_commit" = t && test "$exit" = 0 then merge_was_ok=t exit=1 ;# pretend it left conflicts. fi test "$exit" = 0 || { # The backend exits with 1 when conflicts are left to be resolved, # with 2 when it does not handle the given merge at all. if test "$exit" -eq 1 then cnt=$({ git diff-files --name-only git ls-files --unmerged } | wc -l) if test $best_cnt -le 0 || test $cnt -le $best_cnt then best_strategy=$strategy best_cnt=$cnt fi fi continue } # Automerge succeeded. result_tree=$(git write-tree) && break done # If we have a resulting tree, that means the strategy module # auto resolved the merge cleanly. if test '' != "$result_tree" then if test "$allow_fast_forward" = "t" then parents=$(git merge-base --independent "$head" "$@") else parents=$(git rev-parse "$head" "$@") fi parents=$(echo "$parents" | sed -e 's/^/-p /') result_commit=$(printf '%s\n' "$merge_msg" | git commit-tree $result_tree $parents) || exit finish "$result_commit" "Merge made by $wt_strategy." dropsave exit 0 fi # Pick the result from the best strategy and have the user fix it up. case "$best_strategy" in '') restorestate case "$use_strategies" in ?*' '?*) echo >&2 "No merge strategy handled the merge." ;; *) echo >&2 "Merge with strategy $use_strategies failed." ;; esac exit 2 ;; "$wt_strategy") # We already have its result in the working tree. ;; *) echo "Rewinding the tree to pristine..." restorestate echo "Using the $best_strategy to prepare resolving by hand." git-merge-$best_strategy $common -- "$head_arg" "$@" ;; esac if test "$squash" = t then finish else for remote do echo $remote done >"$GIT_DIR/MERGE_HEAD" printf '%s\n' "$merge_msg" >"$GIT_DIR/MERGE_MSG" || die "Could not write to $GIT_DIR/MERGE_MSG" if test "$allow_fast_forward" != t then printf "%s" no-ff else : fi >"$GIT_DIR/MERGE_MODE" || die "Could not write to $GIT_DIR/MERGE_MODE" fi if test "$merge_was_ok" = t then echo >&2 \ "Automatic merge went well; stopped before committing as requested" exit 0 else { echo ' Conflicts: ' git ls-files --unmerged | sed -e 's/^[^ ]* / /' | uniq } >>"$GIT_DIR/MERGE_MSG" git rerere $rr_arg die "Automatic merge failed; fix conflicts and then commit the result." fi