scripts/git-show-backports - haproxy - Gitiles

 #!/usr/bin/env bash
 #
 # Compares multiple branches against a reference and shows which ones contain
 # each commit, and the level of backports since the origin or its own ancestors.
 #
 # Copyright (c) 2016 Willy Tarreau <w@1wt.eu>
 #
 # The purpose is to make it easy to visualize what backports might be missing
 # in a maintenance branch, and to easily spot the ones that are needed and the
 # ones that are not. It solely relies on the "cherry-picked from" tags in the
 # commit messages to find what commit is available where, and can even find a
 # reference commit's ancestor in another branch's commit ancestors as well to
 # detect that the patch is present. When done with the proper references and
 # a correct ordering of the branches, it can be used to quickly apply a set of
 # fixes to a branch since it dumps suggested commands at the end. When doing
 # so it is a good idea to use "HEAD" as the last branch to avoid doing mistakes.
 #
 # Examples :
 # - find what's in master and not in current branch :
 #   show-backports -q -m -r master HEAD
 # - find what's in 1.6/master and in hapee-maint-1.5r2 but not in current branch :
 #   show-backports -q -m -r 1.6/master hapee-maint-1.5r2 HEAD | grep ' [a-f0-9]\{8\}[-+][0-9] '
 # - check that no recent fix from master is missing in any maintenance branch :
 #   show-backports -r master hapee-maint-1.5r2 aloha-7.5 hapee-maint-1.5r1 aloha-7.0
 # - see what was recently merged into 1.6 and has no equivalent in local master :
 #   show-backports -q -m -r 1.6/master -b "1.6/master@{1 week ago}" master
 # - check what extra backports are present in hapee-r2 compared to hapee-r1 :
 #   show-backports -q -m -r hapee-r2 hapee-r1


 USAGE="Usage: ${0##*/} [-q] [-H] [-m] [-u] [-r reference] [-l logexpr] [-s subject] [-b base] {branch|range} [...] [-- file*]"
 BASES=( )
 BRANCHES=( )
 REF=
 BASE=
 QUIET=
 LOGEXPR=
 SUBJECT=
 MISSING=
 UPSTREAM=
 BODYHASH=

 die() {
 	[ "$#" -eq 0 ] || echo "$*" >&2
 	exit 1
 }

 err() {
 	echo "$*" >&2
 }

 quit() {
 	[ "$#" -eq 0 ] || echo "$*"
 	exit 0
 }

 short() {
 	# git rev-parse --short $1
 	echo "${1::8}"
 }

 dump_commit_matrix() {
 	title=":$REF:"
 	for branch in "${BRANCHES[@]}"; do
 		#echo -n " $branch"
 		title="$title :${branch}:"
 	done
 	title="$title |"

 	count=0
 	# now look up commits
 	while read ref subject; do
 		if [ -n "$MISSING" -a "${subject:0:9}" = "[RELEASE]" ]; then
 			continue
 		fi

 		upstream="none"
 		missing=0
 		refbhash=""
 		line=""
 		for branch in "${BRANCHES[@]}"; do
 			set -- $(grep -m 1 $ref "$WORK/${branch//\//_}")
 			newhash=$1 ; shift
 			bhash=""
 			# count the number of cherry-picks after this one. Since we shift,
 			# the result is in "$#"
 			while [ -n "$1" -a "$1" != "$ref" ]; do
 				shift
 			done
 			if [ -n "$newhash" ]; then
 				line="${line} $(short $newhash)-$#"
 			else
 				# before giving up we can check if our current commit was
 				# itself cherry-picked and check this again. In order not
 				# to have to do it all the time, we can cache the result
 				# for the current line. If a match is found we report it
 				# with the '+' delimiter instead of '-'.
 				if [ "$upstream" = "none" ]; then
 					upstream=( $(git log -1 --pretty --format=%B "$ref" | \
 						sed -n 's/^commit \([^)]*\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]*\))/\1/p') )
 				fi
 				newhash=""
 				for h in ${upstream[@]}; do
 					set -- $(grep -m 1 $h "$WORK/${branch//\//_}")
 					newhash=$1 ; shift
 					while [ -n "$1" -a "$1" != "$h" ]; do
 						shift
 					done
 					if [ -n "$newhash" ]; then
 						line="${line} $(short $newhash)+$#"
 						break
 					fi
 				done
 				if [ -z "$newhash" -a -n "$BODYHASH" ]; then
 					if [ -z "$refbhash" ]; then
 						refbhash=$(git log -1 --pretty="%an|%ae|%at|%B" "$ref" | sed -n '/^\(Signed-off-by\|(cherry picked\)/q;p' | md5sum)
 					fi


 					set -- $(grep -m 1 "H$refbhash\$" "$WORK/${branch//\//_}")
 					newhash=$1 ; shift
 					if [ -n "$newhash" ]; then
 						line="${line} $(short $newhash)+?"
 						break
 					fi
 				fi
 				if [ -z "$newhash" ]; then
 					line="${line} -"
 					missing=1
 				fi
 			fi
 		done
 		line="${line} |"
 		if [ -z "$MISSING" -o $missing -gt 0 ]; then
 			[ $((count++)) -gt 0 ] || echo "$title"
 			[ "$QUIET" != "" -o $count -lt 20 ] || count=0
 			if [ -z "$UPSTREAM" -o "$upstream" = "none" -o -z "$upstream" ]; then
 				echo "$(short $ref) $line"
 			else
 				echo "$(short $upstream) $line"
 			fi
 		fi
 	done < "$WORK/${REF//\//_}"
 }

 while [ -n "$1" -a -z "${1##-*}" ]; do
 	case "$1" in
 		-b)        BASE="$2"      ; shift 2 ;;
 		-r)        REF="$2"       ; shift 2 ;;
 		-l)        LOGEXPR="$2"   ; shift 2 ;;
 		-s)        SUBJECT="$2"   ; shift 2 ;;
 		-q)        QUIET=1        ; shift   ;;
 		-m)        MISSING=1      ; shift   ;;
 		-u)        UPSTREAM=1     ; shift   ;;
 		-H)        BODYHASH=1     ; shift   ;;
 		-h|--help) quit "$USAGE" ;;
 		*)         die  "$USAGE" ;;
 	esac
 done

 # if no ref, either we're checking missing backports and we'll guess
 # the upstream reference branch based on which one contains most of
 # the latest commits, or we'll use master.
 if [ -z "$REF" ]; then
 	if [ -n "$MISSING" ]; then
 		# check the last 10 commits in the base branch, and see where
 		# the seem to be coming from.
 		TAG="$(git describe --tags ${BASE:-HEAD} --abbrev=0)"
 		LAST_COMMITS=( $(git rev-list --abbrev-commit --reverse "$TAG^^.." | tail -n10) )
 		REF=$(for i in "${LAST_COMMITS[@]}"; do
 			upstream=$(git log -1 --pretty --format=%B $i |
 				   sed -n 's/^commit \([^)]*\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]*\))/\1/p' |
 				   tail -n1)
 			if [ -n "$upstream" ]; then
 				# use local first then remote branch
 				( git branch --sort=refname --contains $upstream | head -n1 ;
 				  git branch -r --sort=refname --contains $upstream | head -n1) 2>&1 |
 					grep 'master\|maint' | head -n1
 			fi
 		      done | sort | uniq -c | sort -nr | awk '{ print $NF; exit;}')
 		# here we have a name, e.g. "2.6/master" in REF
 		REF="${REF:-master}"
 		err "Warning! No ref specified, using $REF."
 	else
 		REF=master
 	fi
 fi

 # branches may also appear as id1..id2 to limit the history instead of looking
 # back to the common base. The field is left empty if not set.
 BRANCHES=( )
 BASES=( )
 while [ $# -gt 0 ]; do
         if [ "$1" = "--" ]; then
                 shift
                 break
         fi
 	branch="${1##*..}"
 	if [ "$branch" == "$1" ]; then
 		base=""
 	else
 		base="${1%%..*}"
 	fi
 	BASES[${#BRANCHES[@]}]="$base"
 	BRANCHES[${#BRANCHES[@]}]="$branch"
 	shift
 done

 # args left for git-log
 ARGS=( "$@" )

 if [ ${#BRANCHES[@]} = 0 ]; then
 	if [ -n "$MISSING" ]; then
 		BRANCHES=( HEAD )
 	else
 		die "$USAGE"
 	fi
 fi

 for branch in "$REF" "${BRANCHES[@]}"; do
 	if ! git rev-parse --verify -q "$branch" >/dev/null; then
 		die "Failed to check git branch $branch."
 	fi
 done

 if [ -z "$BASE" -a -n "$MISSING" ]; then
 	err "Warning! No base specified, checking latest backports from current branch since last tag."

 	TAG="$(git describe --tags HEAD --abbrev=0)"
 	COMMITS=( $(git rev-list --abbrev-commit --reverse "$TAG^^..") )
 	tip=""
 	for commit in "${COMMITS[@]}"; do
 		parent=$(git log -1 --pretty --format=%B $commit |
 		         sed -n 's/^commit \([^)]*\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]*\))/\1/p' |
 		         tail -n1)
 		if [ -z "$tip" ]; then
 		        tip=$parent
 		elif [ -n "$parent" ]; then
 		        base=$(git merge-base "$tip" "$parent")
 		        if [ "$base" = "$tip" ]; then
 		                # tip is older than parent, switch tip to it if it
 		                # belongs to the upstream branch
 		                if [ "$(git merge-base $parent $REF)" = "$parent" ]; then
 		                        tip=$parent
 		                fi
 		        fi
 		fi
 	done
 	BASE="$tip"
 	if [ -n "$BASE" ]; then
 	        echo "Restarting from $(git log -1 --no-decorate --oneline $BASE)"
 	else
 		echo "Could not figure the base."
 	fi
 fi

 if [ -z "$BASE" ]; then
 	err "Warning! No base specified, looking for common ancestor."
 	BASE=$(git merge-base --all "$REF" "${BRANCHES[@]}")
 	if [ -z "$BASE" ]; then
 		die "Couldn't find a common ancestor between these branches"
 	fi
 fi

 # we want to go to the git root dir
 DIR="$PWD"
 cd $(git rev-parse --show-toplevel)

 mkdir -p .git/.show-backports #|| die "Can't create .git/.show-backports"
 WORK=.git/.show-backports

 rm -f "$WORK/${REF//\//_}"
 git log --reverse ${LOGEXPR:+--grep $LOGEXPR} --pretty="%H %s" "$BASE".."$REF" -- "${ARGS[@]}" | grep "${SUBJECT}" > "$WORK/${REF//\//_}"

 # for each branch, enumerate all commits and their ancestry

 branch_num=0;
 while [ $branch_num -lt "${#BRANCHES[@]}" ]; do
 	branch="${BRANCHES[$branch_num]}"
 	base="${BASES[$branch_num]}"
 	base="${base:-$BASE}"
 	rm -f "$WORK/${branch//\//_}"
 	git log --reverse --pretty="%H %s" "$base".."$branch" -- "${ARGS[@]}" | grep "${SUBJECT}" | while read h subject; do
 		echo -n "$h" $(git log -1 --pretty --format=%B "$h" | \
 			sed -n 's/^commit \([^)]*\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]*\))/\1/p')
 		if [ -n "$BODYHASH" ]; then
 			echo " H$(git log -1 --pretty="%an|%ae|%at|%B" "$h" | sed -n '/^\(Signed-off-by\|(cherry picked\)/q;p' | md5sum)"
 		else
 			echo
 		fi
 	done > "$WORK/${branch//\//_}"
 	(( branch_num++ ))
 done

 count=0
 dump_commit_matrix | column -t | \
 (
 	left_commits=( )
 	right_commits=( )
 	while read line; do
 		# append the subject at the end of the line
 		set -- $line
 		echo -n "$line "
 		if [ "${line::1}" = ":" ]; then
 			echo "---- Subject ----"
 		else
 			# doing it this way prevents git from abusing the terminal
 			echo "$(git log -1 --pretty="%s" "$1")"
 			left_commits[${#left_commits[@]}]="$1"
 			comm=""
 			while [ -n "$1" -a "$1" != "-" -a "$1" != "|" ]; do
 				comm="${1%-*}"
 				shift
 			done
 			right_commits[${#right_commits[@]}]="$comm"
 		fi
 	done
 	if [ -n "$MISSING" -a ${#left_commits[@]} -eq 0 ]; then
 		echo "No missing commit to apply."
 	elif [ -n "$MISSING" ]; then
 		echo
 		echo
 		echo "In order to show and/or apply all leftmost commits to current branch :"
 		echo "   git show --pretty=format:'%C(yellow)commit  %H%C(normal)%nAuthor: %an <%ae>%nDate:   %aD%n%n%C(green)%C(bold)git cherry-pick -sx %h%n%n%w(0,4,4)%B%N' ${left_commits[@]}"
 		echo
 		echo "   git cherry-pick -sx ${left_commits[@]}"
 		echo
 		if [ "${left_commits[*]}" != "${right_commits[*]}" ]; then
 			echo "In order to show and/or apply all rightmost commits to current branch :"
 			echo "   git show --pretty=format:'%C(yellow)commit  %H%C(normal)%nAuthor: %an <%ae>%nDate:   %aD%n%n%C(green)%C(bold)git cherry-pick -sx %h%n%n%w(0,4,4)%B%N' ${right_commits[@]}"
 			echo
 			echo "   git cherry-pick -sx ${right_commits[@]}"
 			echo
 		fi
 	fi
 )
	#!/usr/bin/env bash
	#
	# Compares multiple branches against a reference and shows which ones contain
	# each commit, and the level of backports since the origin or its own ancestors.
	#
	# Copyright (c) 2016 Willy Tarreau <w@1wt.eu>
	#
	# The purpose is to make it easy to visualize what backports might be missing
	# in a maintenance branch, and to easily spot the ones that are needed and the
	# ones that are not. It solely relies on the "cherry-picked from" tags in the
	# commit messages to find what commit is available where, and can even find a
	# reference commit's ancestor in another branch's commit ancestors as well to
	# detect that the patch is present. When done with the proper references and
	# a correct ordering of the branches, it can be used to quickly apply a set of
	# fixes to a branch since it dumps suggested commands at the end. When doing
	# so it is a good idea to use "HEAD" as the last branch to avoid doing mistakes.
	#
	# Examples :
	# - find what's in master and not in current branch :
	# show-backports -q -m -r master HEAD
	# - find what's in 1.6/master and in hapee-maint-1.5r2 but not in current branch :
	# show-backports -q -m -r 1.6/master hapee-maint-1.5r2 HEAD \| grep ' [a-f0-9]\{8\}[-+][0-9] '
	# - check that no recent fix from master is missing in any maintenance branch :
	# show-backports -r master hapee-maint-1.5r2 aloha-7.5 hapee-maint-1.5r1 aloha-7.0
	# - see what was recently merged into 1.6 and has no equivalent in local master :
	# show-backports -q -m -r 1.6/master -b "1.6/master@{1 week ago}" master
	# - check what extra backports are present in hapee-r2 compared to hapee-r1 :
	# show-backports -q -m -r hapee-r2 hapee-r1


	USAGE="Usage: ${0##/} [-q] [-H] [-m] [-u] [-r reference] [-l logexpr] [-s subject] [-b base] {branch\|range} [...] [-- file]"
	BASES=( )
	BRANCHES=( )
	REF=
	BASE=
	QUIET=
	LOGEXPR=
	SUBJECT=
	MISSING=
	UPSTREAM=
	BODYHASH=

	die() {
	[ "$#" -eq 0 ] \|\| echo "$*" >&2
	exit 1
	}

	err() {
	echo "$*" >&2
	}

	quit() {
	[ "$#" -eq 0 ] \|\| echo "$*"
	exit 0
	}

	short() {
	# git rev-parse --short $1
	echo "${1::8}"
	}

	dump_commit_matrix() {
	title=":$REF:"
	for branch in "${BRANCHES[@]}"; do
	#echo -n " $branch"
	title="$title :${branch}:"
	done
	title="$title \|"

	count=0
	# now look up commits
	while read ref subject; do
	if [ -n "$MISSING" -a "${subject:0:9}" = "[RELEASE]" ]; then
	continue
	fi

	upstream="none"
	missing=0
	refbhash=""
	line=""
	for branch in "${BRANCHES[@]}"; do
	set -- $(grep -m 1 $ref "$WORK/${branch//\//_}")
	newhash=$1 ; shift
	bhash=""
	# count the number of cherry-picks after this one. Since we shift,
	# the result is in "$#"
	while [ -n "$1" -a "$1" != "$ref" ]; do
	shift
	done
	if [ -n "$newhash" ]; then
	line="${line} $(short $newhash)-$#"
	else
	# before giving up we can check if our current commit was
	# itself cherry-picked and check this again. In order not
	# to have to do it all the time, we can cache the result
	# for the current line. If a match is found we report it
	# with the '+' delimiter instead of '-'.
	if [ "$upstream" = "none" ]; then
	upstream=( $(git log -1 --pretty --format=%B "$ref" \| \
	sed -n 's/^commit \([^)]\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]\))/\1/p') )
	fi
	newhash=""
	for h in ${upstream[@]}; do
	set -- $(grep -m 1 $h "$WORK/${branch//\//_}")
	newhash=$1 ; shift
	while [ -n "$1" -a "$1" != "$h" ]; do
	shift
	done
	if [ -n "$newhash" ]; then
	line="${line} $(short $newhash)+$#"
	break
	fi
	done
	if [ -z "$newhash" -a -n "$BODYHASH" ]; then
	if [ -z "$refbhash" ]; then
	refbhash=$(git log -1 --pretty="%an\|%ae\|%at\|%B" "$ref" \| sed -n '/^\(Signed-off-by\\|(cherry picked\)/q;p' \| md5sum)
	fi


	set -- $(grep -m 1 "H$refbhash\$" "$WORK/${branch//\//_}")
	newhash=$1 ; shift
	if [ -n "$newhash" ]; then
	line="${line} $(short $newhash)+?"
	break
	fi
	fi
	if [ -z "$newhash" ]; then
	line="${line} -"
	missing=1
	fi
	fi
	done
	line="${line} \|"
	if [ -z "$MISSING" -o $missing -gt 0 ]; then
	[ $((count++)) -gt 0 ] \|\| echo "$title"
	[ "$QUIET" != "" -o $count -lt 20 ] \|\| count=0
	if [ -z "$UPSTREAM" -o "$upstream" = "none" -o -z "$upstream" ]; then
	echo "$(short $ref) $line"
	else
	echo "$(short $upstream) $line"
	fi
	fi
	done < "$WORK/${REF//\//_}"
	}

	while [ -n "$1" -a -z "${1##-*}" ]; do
	case "$1" in
	-b) BASE="$2" ; shift 2 ;;
	-r) REF="$2" ; shift 2 ;;
	-l) LOGEXPR="$2" ; shift 2 ;;
	-s) SUBJECT="$2" ; shift 2 ;;
	-q) QUIET=1 ; shift ;;
	-m) MISSING=1 ; shift ;;
	-u) UPSTREAM=1 ; shift ;;
	-H) BODYHASH=1 ; shift ;;
	-h\|--help) quit "$USAGE" ;;
	*) die "$USAGE" ;;
	esac
	done

	# if no ref, either we're checking missing backports and we'll guess
	# the upstream reference branch based on which one contains most of
	# the latest commits, or we'll use master.
	if [ -z "$REF" ]; then
	if [ -n "$MISSING" ]; then
	# check the last 10 commits in the base branch, and see where
	# the seem to be coming from.
	TAG="$(git describe --tags ${BASE:-HEAD} --abbrev=0)"
	LAST_COMMITS=( $(git rev-list --abbrev-commit --reverse "$TAG^^.." \| tail -n10) )
	REF=$(for i in "${LAST_COMMITS[@]}"; do
	upstream=$(git log -1 --pretty --format=%B $i \|
	sed -n 's/^commit \([^)]\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]\))/\1/p' \|
	tail -n1)
	if [ -n "$upstream" ]; then
	# use local first then remote branch
	( git branch --sort=refname --contains $upstream \| head -n1 ;
	git branch -r --sort=refname --contains $upstream \| head -n1) 2>&1 \|
	grep 'master\\|maint' \| head -n1
	fi
	done \| sort \| uniq -c \| sort -nr \| awk '{ print $NF; exit;}')
	# here we have a name, e.g. "2.6/master" in REF
	REF="${REF:-master}"
	err "Warning! No ref specified, using $REF."
	else
	REF=master
	fi
	fi

	# branches may also appear as id1..id2 to limit the history instead of looking
	# back to the common base. The field is left empty if not set.
	BRANCHES=( )
	BASES=( )
	while [ $# -gt 0 ]; do
	if [ "$1" = "--" ]; then
	shift
	break
	fi
	branch="${1##*..}"
	if [ "$branch" == "$1" ]; then
	base=""
	else
	base="${1%%..*}"
	fi
	BASES[${#BRANCHES[@]}]="$base"
	BRANCHES[${#BRANCHES[@]}]="$branch"
	shift
	done

	# args left for git-log
	ARGS=( "$@" )

	if [ ${#BRANCHES[@]} = 0 ]; then
	if [ -n "$MISSING" ]; then
	BRANCHES=( HEAD )
	else
	die "$USAGE"
	fi
	fi

	for branch in "$REF" "${BRANCHES[@]}"; do
	if ! git rev-parse --verify -q "$branch" >/dev/null; then
	die "Failed to check git branch $branch."
	fi
	done

	if [ -z "$BASE" -a -n "$MISSING" ]; then
	err "Warning! No base specified, checking latest backports from current branch since last tag."

	TAG="$(git describe --tags HEAD --abbrev=0)"
	COMMITS=( $(git rev-list --abbrev-commit --reverse "$TAG^^..") )
	tip=""
	for commit in "${COMMITS[@]}"; do
	parent=$(git log -1 --pretty --format=%B $commit \|
	sed -n 's/^commit \([^)]\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]\))/\1/p' \|
	tail -n1)
	if [ -z "$tip" ]; then
	tip=$parent
	elif [ -n "$parent" ]; then
	base=$(git merge-base "$tip" "$parent")
	if [ "$base" = "$tip" ]; then
	# tip is older than parent, switch tip to it if it
	# belongs to the upstream branch
	if [ "$(git merge-base $parent $REF)" = "$parent" ]; then
	tip=$parent
	fi
	fi
	fi
	done
	BASE="$tip"
	if [ -n "$BASE" ]; then
	echo "Restarting from $(git log -1 --no-decorate --oneline $BASE)"
	else
	echo "Could not figure the base."
	fi
	fi

	if [ -z "$BASE" ]; then
	err "Warning! No base specified, looking for common ancestor."
	BASE=$(git merge-base --all "$REF" "${BRANCHES[@]}")
	if [ -z "$BASE" ]; then
	die "Couldn't find a common ancestor between these branches"
	fi
	fi

	# we want to go to the git root dir
	DIR="$PWD"
	cd $(git rev-parse --show-toplevel)

	mkdir -p .git/.show-backports #\|\| die "Can't create .git/.show-backports"
	WORK=.git/.show-backports

	rm -f "$WORK/${REF//\//_}"
	git log --reverse ${LOGEXPR:+--grep $LOGEXPR} --pretty="%H %s" "$BASE".."$REF" -- "${ARGS[@]}" \| grep "${SUBJECT}" > "$WORK/${REF//\//_}"

	# for each branch, enumerate all commits and their ancestry

	branch_num=0;
	while [ $branch_num -lt "${#BRANCHES[@]}" ]; do
	branch="${BRANCHES[$branch_num]}"
	base="${BASES[$branch_num]}"
	base="${base:-$BASE}"
	rm -f "$WORK/${branch//\//_}"
	git log --reverse --pretty="%H %s" "$base".."$branch" -- "${ARGS[@]}" \| grep "${SUBJECT}" \| while read h subject; do
	echo -n "$h" $(git log -1 --pretty --format=%B "$h" \| \
	sed -n 's/^commit \([^)]\) upstream\.$/\1/p;s/^(cherry picked from commit \([^)]\))/\1/p')
	if [ -n "$BODYHASH" ]; then
	echo " H$(git log -1 --pretty="%an\|%ae\|%at\|%B" "$h" \| sed -n '/^\(Signed-off-by\\|(cherry picked\)/q;p' \| md5sum)"
	else
	echo
	fi
	done > "$WORK/${branch//\//_}"
	(( branch_num++ ))
	done

	count=0
	dump_commit_matrix \| column -t \| \
	(
	left_commits=( )
	right_commits=( )
	while read line; do
	# append the subject at the end of the line
	set -- $line
	echo -n "$line "
	if [ "${line::1}" = ":" ]; then
	echo "---- Subject ----"
	else
	# doing it this way prevents git from abusing the terminal
	echo "$(git log -1 --pretty="%s" "$1")"
	left_commits[${#left_commits[@]}]="$1"
	comm=""
	while [ -n "$1" -a "$1" != "-" -a "$1" != "\|" ]; do
	comm="${1%-*}"
	shift
	done
	right_commits[${#right_commits[@]}]="$comm"
	fi
	done
	if [ -n "$MISSING" -a ${#left_commits[@]} -eq 0 ]; then
	echo "No missing commit to apply."
	elif [ -n "$MISSING" ]; then
	echo
	echo
	echo "In order to show and/or apply all leftmost commits to current branch :"
	echo " git show --pretty=format:'%C(yellow)commit %H%C(normal)%nAuthor: %an <%ae>%nDate: %aD%n%n%C(green)%C(bold)git cherry-pick -sx %h%n%n%w(0,4,4)%B%N' ${left_commits[@]}"
	echo
	echo " git cherry-pick -sx ${left_commits[@]}"
	echo
	if [ "${left_commits[]}" != "${right_commits[]}" ]; then
	echo "In order to show and/or apply all rightmost commits to current branch :"
	echo " git show --pretty=format:'%C(yellow)commit %H%C(normal)%nAuthor: %an <%ae>%nDate: %aD%n%n%C(green)%C(bold)git cherry-pick -sx %h%n%n%w(0,4,4)%B%N' ${right_commits[@]}"
	echo
	echo " git cherry-pick -sx ${right_commits[@]}"
	echo
	fi
	fi
	)