[thirdparty/git.git] / mergetools / vimdiff

# This script can be run in two different contexts:
#
#   - From git, when the user invokes the "vimdiff" merge tool. In this context
#     this script expects the following environment variables (among others) to
#     be defined (which is something "git" takes care of):
#
#       - $BASE
#       - $LOCAL
#       - $REMOTE
#       - $MERGED
#
#     In this mode, all this script does is to run the next command:
#
#         vim -f -c ... $LOCAL $BASE $REMOTE $MERGED
#
#     ...where the "..." string depends on the value of the
#     "mergetool.vimdiff.layout" configuration variable and is used to open vim
#     with a certain layout of buffers, windows and tabs.
#
#   - From a script inside the unit tests framework folder ("t" folder) by
#     sourcing this script and then manually calling "run_unit_tests", which
#     will run a battery of unit tests to make sure nothing breaks.
#     In this context this script does not expect any particular environment
#     variable to be set.


################################################################################
## Internal functions (not meant to be used outside this script)
################################################################################

debug_print () {
	# Send message to stderr if global variable GIT_MERGETOOL_VIMDIFF_DEBUG
	# is set.

	if test -n "$GIT_MERGETOOL_VIMDIFF_DEBUG"
	then
		>&2 echo "$@"
	fi
}

substring () {
	# Return a substring of $1 containing $3 characters starting at
	# zero-based offset $2.
	#
	# Examples:
	#
	#   substring "Hello world" 0 4  --> "Hell"
	#   substring "Hello world" 3 4  --> "lo w"
	#   substring "Hello world" 3 10 --> "lo world"

	STRING=$1
	START=$2
	LEN=$3

	echo "$STRING" | cut -c$(( START + 1 ))-$(( START + $LEN ))
}

gen_cmd_aux () {
	# Auxiliary function used from "gen_cmd()".
	# Read that other function documentation for more details.

	LAYOUT=$1
	CMD=$2  # This is a second (hidden) argument used for recursion

	debug_print
	debug_print "LAYOUT    : $LAYOUT"
	debug_print "CMD       : $CMD"

	start=0
	end=${#LAYOUT}

	nested=0
	nested_min=100

	# Step 1:
	#
	# Increase/decrease "start"/"end" indices respectively to get rid of
	# outer parenthesis.
	#
	# Example:
	#
	#   - BEFORE: (( LOCAL , BASE ) / MERGED )
	#   - AFTER :  ( LOCAL , BASE ) / MERGED

	oldIFS=$IFS
	IFS=#
	for c in $(echo "$LAYOUT" | sed 's:.:&#:g')
	do
		if test -z "$c" || test "$c" = " "
		then
			continue
		fi

		if test "$c" = "("
		then
			nested=$(( nested + 1 ))
			continue
		fi

		if test "$c" = ")"
		then
			nested=$(( nested - 1 ))
			continue
		fi

		if test "$nested" -lt "$nested_min"
		then
			nested_min=$nested
		fi
	done
	IFS=$oldIFS

	debug_print "NESTED MIN: $nested_min"

	while test "$nested_min" -gt "0"
	do
		start=$(( start + 1 ))
		end=$(( end - 1 ))

		start_minus_one=$(( start - 1 ))

		while ! test "$(substring "$LAYOUT" "$start_minus_one" 1)" = "("
		do
			start=$(( start + 1 ))
			start_minus_one=$(( start_minus_one + 1 ))
		done

		while ! test "$(substring "$LAYOUT" "$end" 1)" = ")"
		do
			end=$(( end - 1 ))
		done

		nested_min=$(( nested_min - 1 ))
	done

	debug_print "CLEAN     : $(substring "$LAYOUT" "$start" "$(( end - start ))")"


	# Step 2:
	#
	# Search for all valid separators ("/" or ",") which are *not*
	# inside parenthesis. Save the index at which each of them makes the
	# first appearance.

	index_horizontal_split=""
	index_vertical_split=""

	nested=0
	i=$(( start - 1 ))

	oldIFS=$IFS
	IFS=#
	for c in $(substring "$LAYOUT" "$start" "$(( end - start ))" | sed 's:.:&#:g');
	do
		i=$(( i + 1 ))

		if test "$c" = " "
		then
			continue
		fi

		if test "$c" = "("
		then
			nested=$(( nested + 1 ))
			continue
		fi

		if test "$c" = ")"
		then
			nested=$(( nested - 1 ))
			continue
		fi

		if test "$nested" = 0
		then
			current=$c

			if test "$current" = "/"
			then
				if test -z "$index_horizontal_split"
				then
					index_horizontal_split=$i
				fi

			elif test "$current" = ","
			then
				if test -z "$index_vertical_split"
				then
					index_vertical_split=$i
				fi
			fi
		fi
	done
	IFS=$oldIFS


	# Step 3:
	#
	# Process the separator with the highest order of precedence
	# (";" has the highest precedence and "|" the lowest one).
	#
	# By "process" I mean recursively call this function twice: the first
	# one with the substring at the left of the separator and the second one
	# with the one at its right.

	terminate="false"

	if ! test -z "$index_horizontal_split"
	then
		before="leftabove split"
		after="wincmd j"
		index=$index_horizontal_split
		terminate="true"

	elif ! test -z "$index_vertical_split"
	then
		before="leftabove vertical split"
		after="wincmd l"
		index=$index_vertical_split
		terminate="true"
	fi

	if  test "$terminate" = "true"
	then
		CMD="$CMD | $before"
		CMD=$(gen_cmd_aux "$(substring "$LAYOUT" "$start" "$(( index - start ))")" "$CMD")
		CMD="$CMD | $after"
		CMD=$(gen_cmd_aux "$(substring "$LAYOUT" "$(( index + 1 ))" "$(( ${#LAYOUT} - index ))")" "$CMD")
		echo "$CMD"
		return
	fi


	# Step 4:
	#
	# If we reach this point, it means there are no separators and we just
	# need to print the command to display the specified buffer

	target=$(substring "$LAYOUT" "$start" "$(( end - start ))" | sed 's:[ @();|-]::g')

	if test "$target" = "LOCAL"
	then
		CMD="$CMD | 1b"

	elif test "$target" = "BASE"
	then
		CMD="$CMD | 2b"

	elif test "$target" = "REMOTE"
	then
		CMD="$CMD | 3b"

	elif test "$target" = "MERGED"
	then
		CMD="$CMD | 4b"

	else
		CMD="$CMD | ERROR: >$target<"
	fi

	echo "$CMD"
	return
}


gen_cmd () {
	# This function returns (in global variable FINAL_CMD) the string that
	# you can use when invoking "vim" (as shown next) to obtain a given
	# layout:
	#
	#   $ vim -f $FINAL_CMD "$LOCAL" "$BASE" "$REMOTE" "$MERGED"
	#
	# It takes one single argument: a string containing the desired layout
	# definition.
	#
	# The syntax of the "layout definitions" is explained in "Documentation/
	# mergetools/vimdiff.txt" but you can already intuitively understand how
	# it works by knowing that...
	#
	#   * "+" means "a new vim tab"
	#   * "/" means "a new vim horizontal split"
	#   * "," means "a new vim vertical split"
	#
	# It also returns (in global variable FINAL_TARGET) the name ("LOCAL",
	# "BASE", "REMOTE" or "MERGED") of the file that is marked with an "@",
	# or "MERGED" if none of them is.
	#
	# Example:
	#
	#     gen_cmd "@LOCAL , REMOTE"
	#     |
	#     `-> FINAL_CMD    == "-c \"echo | leftabove vertical split | 1b | wincmd l | 3b | tabdo windo diffthis\" -c \"tabfirst\""
	#         FINAL_TARGET == "LOCAL"

	LAYOUT=$1


	# Search for a "@" in one of the files identifiers ("LOCAL", "BASE",
	# "REMOTE", "MERGED"). If not found, use "MERGE" as the default file
	# where changes will be saved.

	if echo "$LAYOUT" | grep @LOCAL >/dev/null
	then
		FINAL_TARGET="LOCAL"
	elif echo "$LAYOUT" | grep @BASE >/dev/null
	then
		FINAL_TARGET="BASE"
	else
		FINAL_TARGET="MERGED"
	fi


	# Obtain the first part of vim "-c" option to obtain the desired layout

	CMD=
	oldIFS=$IFS
	IFS=+
	for tab in $LAYOUT
	do
		if test -z "$CMD"
		then
			CMD="echo" # vim "nop" operator
		else
			CMD="$CMD | tabnew"
		fi

		# If this is a single window diff with all the buffers
		if ! echo "$tab" | grep ",\|/" >/dev/null
		then
			CMD="$CMD | silent execute 'bufdo diffthis'"
		fi

		CMD=$(gen_cmd_aux "$tab" "$CMD")
	done
	IFS=$oldIFS

	CMD="$CMD | execute 'tabdo windo diffthis'"

	FINAL_CMD="-c \"set hidden diffopt-=hiddenoff | $CMD | tabfirst\""
}


################################################################################
## API functions (called from "git-mergetool--lib.sh")
################################################################################

diff_cmd () {
	"$merge_tool_path" -R -f -d \
		-c 'wincmd l' -c 'cd $GIT_PREFIX' "$LOCAL" "$REMOTE"
}


diff_cmd_help () {
	TOOL=$1

	case "$TOOL" in
	nvimdiff*)
		printf "Use Neovim"
		;;
	gvimdiff*)
		printf "Use gVim (requires a graphical session)"
		;;
	vimdiff*)
		printf "Use Vim"
		;;
	esac

	return 0
}


merge_cmd () {
	TOOL=$1

	layout=$(git config "mergetool.$TOOL.layout")

	# backward compatibility:
	if test -z "$layout"
	then
		layout=$(git config mergetool.vimdiff.layout)
	fi

	case "$TOOL" in
	*vimdiff)
		if test -z "$layout"
		then
			# Default layout when none is specified
			layout="(LOCAL,BASE,REMOTE)/MERGED"
		fi
		;;
	*vimdiff1)
		layout="@LOCAL,REMOTE"
		;;
	*vimdiff2)
		layout="LOCAL,MERGED,REMOTE"
		;;
	*vimdiff3)
		layout="MERGED"
		;;
	esac

	gen_cmd "$layout"

	debug_print ""
	debug_print "FINAL CMD : $FINAL_CMD"
	debug_print "FINAL TAR : $FINAL_TARGET"

	if $base_present
	then
		eval '"$merge_tool_path"' \
			-f "$FINAL_CMD" '"$LOCAL"' '"$BASE"' '"$REMOTE"' '"$MERGED"'
	else
		# If there is no BASE (example: a merge conflict in a new file
		# with the same name created in both braches which didn't exist
		# before), close all BASE windows using vim's "quit" command

		FINAL_CMD=$(echo "$FINAL_CMD" | \
			sed -e 's:2b:quit:g' -e 's:3b:2b:g' -e 's:4b:3b:g')

		eval '"$merge_tool_path"' \
			-f "$FINAL_CMD" '"$LOCAL"' '"$REMOTE"' '"$MERGED"'
	fi

	ret="$?"

	if test "$ret" -eq 0
	then
		case "$FINAL_TARGET" in
		LOCAL)
			source_path="$LOCAL"
			;;
		REMOTE)
			source_path="$REMOTE"
			;;
		MERGED|*)
			# Do nothing
			source_path=
			;;
		esac

		if test -n "$source_path"
		then
			cp "$source_path" "$MERGED"
		fi
	fi

	return "$ret"
}


merge_cmd_help () {
	TOOL=$1

	case "$TOOL" in
	nvimdiff*)
		printf "Use Neovim "
		;;
	gvimdiff*)
		printf "Use gVim (requires a graphical session) "
		;;
	vimdiff*)
		printf "Use Vim "
		;;
	esac

	case "$TOOL" in
	*1)
		echo "with a 2 panes layout (LOCAL and REMOTE)"
		;;
	*2)
		echo "with a 3 panes layout (LOCAL, MERGED and REMOTE)"
		;;
	*3)
		echo "where only the MERGED file is shown"
		;;
	*)
		echo "with a custom layout (see \`git help mergetool\`'s \`BACKEND SPECIFIC HINTS\` section)"
		;;
	esac

	return 0
}


translate_merge_tool_path () {
	case "$1" in
	nvimdiff*)
		echo nvim
		;;
	gvimdiff*)
		echo gvim
		;;
	vimdiff*)
		echo vim
		;;
	esac
}


exit_code_trustable () {
	true
}


list_tool_variants () {
	if test "$TOOL_MODE" = "diff"
	then
		for prefix in '' g n
		do
			echo "${prefix}vimdiff"
		done
	else
		for prefix in '' g n
		do
			for suffix in '' 1 2 3
			do
				echo "${prefix}vimdiff${suffix}"
			done
		done
	fi
}


################################################################################
## Unit tests (called from scripts inside the "t" folder)
################################################################################

run_unit_tests () {
	# Function to make sure that we don't break anything when modifying this
	# script.

	NUMBER_OF_TEST_CASES=16

	TEST_CASE_01="(LOCAL,BASE,REMOTE)/MERGED"   # default behaviour
	TEST_CASE_02="@LOCAL,REMOTE"                # when using vimdiff1
	TEST_CASE_03="LOCAL,MERGED,REMOTE"          # when using vimdiff2
	TEST_CASE_04="MERGED"                       # when using vimdiff3
	TEST_CASE_05="LOCAL/MERGED/REMOTE"
	TEST_CASE_06="(LOCAL/REMOTE),MERGED"
	TEST_CASE_07="MERGED,(LOCAL/REMOTE)"
	TEST_CASE_08="(LOCAL,REMOTE)/MERGED"
	TEST_CASE_09="MERGED/(LOCAL,REMOTE)"
	TEST_CASE_10="(LOCAL/BASE/REMOTE),MERGED"
	TEST_CASE_11="(LOCAL,BASE,REMOTE)/MERGED+BASE,LOCAL+BASE,REMOTE+(LOCAL/BASE/REMOTE),MERGED"
	TEST_CASE_12="((LOCAL,REMOTE)/BASE),MERGED"
	TEST_CASE_13="((LOCAL,REMOTE)/BASE),((LOCAL/REMOTE),MERGED)"
	TEST_CASE_14="BASE,REMOTE+BASE,LOCAL"
	TEST_CASE_15="  ((  (LOCAL , BASE , REMOTE) / MERGED))   +(BASE)   , LOCAL+ BASE , REMOTE+ (((LOCAL / BASE / REMOTE)) ,    MERGED   )  "
	TEST_CASE_16="LOCAL,BASE,REMOTE / MERGED + BASE,LOCAL + BASE,REMOTE + (LOCAL / BASE / REMOTE),MERGED"

	EXPECTED_CMD_01="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | leftabove vertical split | 1b | wincmd l | leftabove vertical split | 2b | wincmd l | 3b | wincmd j | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_02="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | 1b | wincmd l | 3b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_03="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | 1b | wincmd l | leftabove vertical split | 4b | wincmd l | 3b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_04="-c \"set hidden diffopt-=hiddenoff | echo | silent execute 'bufdo diffthis' | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_05="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | 1b | wincmd j | leftabove split | 4b | wincmd j | 3b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_06="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | leftabove split | 1b | wincmd j | 3b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_07="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | 4b | wincmd l | leftabove split | 1b | wincmd j | 3b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_08="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | leftabove vertical split | 1b | wincmd l | 3b | wincmd j | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_09="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | 4b | wincmd j | leftabove vertical split | 1b | wincmd l | 3b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_10="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | leftabove split | 1b | wincmd j | leftabove split | 2b | wincmd j | 3b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_11="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | leftabove vertical split | 1b | wincmd l | leftabove vertical split | 2b | wincmd l | 3b | wincmd j | 4b | tabnew | leftabove vertical split | 2b | wincmd l | 1b | tabnew | leftabove vertical split | 2b | wincmd l | 3b | tabnew | leftabove vertical split | leftabove split | 1b | wincmd j | leftabove split | 2b | wincmd j | 3b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_12="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | leftabove split | leftabove vertical split | 1b | wincmd l | 3b | wincmd j | 2b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_13="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | leftabove split | leftabove vertical split | 1b | wincmd l | 3b | wincmd j | 2b | wincmd l | leftabove vertical split | leftabove split | 1b | wincmd j | 3b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_14="-c \"set hidden diffopt-=hiddenoff | echo | leftabove vertical split | 2b | wincmd l | 3b | tabnew | leftabove vertical split | 2b | wincmd l | 1b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_15="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | leftabove vertical split | 1b | wincmd l | leftabove vertical split | 2b | wincmd l | 3b | wincmd j | 4b | tabnew | leftabove vertical split | 2b | wincmd l | 1b | tabnew | leftabove vertical split | 2b | wincmd l | 3b | tabnew | leftabove vertical split | leftabove split | 1b | wincmd j | leftabove split | 2b | wincmd j | 3b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""
	EXPECTED_CMD_16="-c \"set hidden diffopt-=hiddenoff | echo | leftabove split | leftabove vertical split | 1b | wincmd l | leftabove vertical split | 2b | wincmd l | 3b | wincmd j | 4b | tabnew | leftabove vertical split | 2b | wincmd l | 1b | tabnew | leftabove vertical split | 2b | wincmd l | 3b | tabnew | leftabove vertical split | leftabove split | 1b | wincmd j | leftabove split | 2b | wincmd j | 3b | wincmd l | 4b | execute 'tabdo windo diffthis' | tabfirst\""

	EXPECTED_TARGET_01="MERGED"
	EXPECTED_TARGET_02="LOCAL"
	EXPECTED_TARGET_03="MERGED"
	EXPECTED_TARGET_04="MERGED"
	EXPECTED_TARGET_05="MERGED"
	EXPECTED_TARGET_06="MERGED"
	EXPECTED_TARGET_07="MERGED"
	EXPECTED_TARGET_08="MERGED"
	EXPECTED_TARGET_09="MERGED"
	EXPECTED_TARGET_10="MERGED"
	EXPECTED_TARGET_11="MERGED"
	EXPECTED_TARGET_12="MERGED"
	EXPECTED_TARGET_13="MERGED"
	EXPECTED_TARGET_14="MERGED"
	EXPECTED_TARGET_15="MERGED"
	EXPECTED_TARGET_16="MERGED"

	at_least_one_ko="false"

	for i in $(seq -w 1 99)
	do
		if test "$i" -gt $NUMBER_OF_TEST_CASES
		then
			break
		fi

		gen_cmd "$(eval echo \${TEST_CASE_"$i"})"

		if test "$FINAL_CMD" = "$(eval echo \${EXPECTED_CMD_"$i"})" \
			&& test "$FINAL_TARGET" = "$(eval echo \${EXPECTED_TARGET_"$i"})"
		then
			printf "Test Case #%02d: OK\n" "$(echo "$i" | sed 's/^0*//')"
		else
			printf "Test Case #%02d: KO !!!!\n" "$(echo "$i" | sed 's/^0*//')"
			echo "  FINAL_CMD              : $FINAL_CMD"
			echo "  FINAL_CMD (expected)   : $(eval echo \${EXPECTED_CMD_"$i"})"
			echo "  FINAL_TARGET           : $FINAL_TARGET"
			echo "  FINAL_TARGET (expected): $(eval echo \${EXPECTED_TARGET_"$i"})"
			at_least_one_ko="true"
		fi
	done

	# verify that `merge_cmd` handles paths with spaces
	record_parameters () {
		>actual
		for arg
		do
			echo "$arg" >>actual
		done
	}

	base_present=false
	LOCAL='lo cal'
	BASE='ba se'
	REMOTE="' '"
	MERGED='mer ged'
	merge_tool_path=record_parameters

	merge_cmd vimdiff || at_least_one_ko=true

	cat >expect <<-\EOF
	-f
	-c
	set hidden diffopt-=hiddenoff | echo | leftabove split | leftabove vertical split | 1b | wincmd l | leftabove vertical split | quit | wincmd l | 2b | wincmd j | 3b | execute 'tabdo windo diffthis' | tabfirst
	lo cal
	' '
	mer ged
	EOF

	diff -u expect actual || at_least_one_ko=true

	if test "$at_least_one_ko" = "true"
	then
		return 255
	else
		return 0
	fi
}
Commit	Line	Data
	1	# This script can be run in two different contexts:
	2	#
	3	# - From git, when the user invokes the "vimdiff" merge tool. In this context
	4	# this script expects the following environment variables (among others) to
	5	# be defined (which is something "git" takes care of):
	6	#
	7	# - $BASE
	8	# - $LOCAL
	9	# - $REMOTE
	10	# - $MERGED
	11	#
	12	# In this mode, all this script does is to run the next command:
	13	#
	14	# vim -f -c ... $LOCAL $BASE $REMOTE $MERGED
	15	#
	16	# ...where the "..." string depends on the value of the
	17	# "mergetool.vimdiff.layout" configuration variable and is used to open vim
	18	# with a certain layout of buffers, windows and tabs.
	19	#
	20	# - From a script inside the unit tests framework folder ("t" folder) by
	21	# sourcing this script and then manually calling "run_unit_tests", which
	22	# will run a battery of unit tests to make sure nothing breaks.
	23	# In this context this script does not expect any particular environment
	24	# variable to be set.
	25
	26
	27	################################################################################
	28	## Internal functions (not meant to be used outside this script)
	29	################################################################################
	30
	31	debug_print () {
	32	# Send message to stderr if global variable GIT_MERGETOOL_VIMDIFF_DEBUG
	33	# is set.
	34
	35	if test -n "$GIT_MERGETOOL_VIMDIFF_DEBUG"
	36	then
	37	>&2 echo "$@"
	38	fi
	39	}
	40
	41	substring () {
	42	# Return a substring of $1 containing $3 characters starting at
	43	# zero-based offset $2.
	44	#
	45	# Examples:
	46	#
	47	# substring "Hello world" 0 4 --> "Hell"
	48	# substring "Hello world" 3 4 --> "lo w"
	49	# substring "Hello world" 3 10 --> "lo world"
	50
	51	STRING=$1
	52	START=$2
	53	LEN=$3
	54
	55	echo "$STRING" \| cut -c$(( START + 1 ))-$(( START + $LEN ))
	56	}
	57
	58	gen_cmd_aux () {
	59	# Auxiliary function used from "gen_cmd()".
	60	# Read that other function documentation for more details.
	61
	62	LAYOUT=$1
	63	CMD=$2 # This is a second (hidden) argument used for recursion
	64
	65	debug_print
	66	debug_print "LAYOUT : $LAYOUT"
	67	debug_print "CMD : $CMD"
	68
	69	start=0
	70	end=${#LAYOUT}
	71
	72	nested=0
	73	nested_min=100
	74
	75	# Step 1:
	76	#
	77	# Increase/decrease "start"/"end" indices respectively to get rid of
	78	# outer parenthesis.
	79	#
	80	# Example:
	81	#
	82	# - BEFORE: (( LOCAL , BASE ) / MERGED )
	83	# - AFTER : ( LOCAL , BASE ) / MERGED
	84
	85	oldIFS=$IFS
	86	IFS=#
	87	for c in $(echo "$LAYOUT" \| sed 's:.:&#:g')
	88	do
	89	if test -z "$c" \|\| test "$c" = " "
	90	then
	91	continue
	92	fi
	93
	94	if test "$c" = "("
	95	then
	96	nested=$(( nested + 1 ))
	97	continue
	98	fi
	99
	100	if test "$c" = ")"
	101	then
	102	nested=$(( nested - 1 ))
	103	continue
	104	fi
	105
	106	if test "$nested" -lt "$nested_min"
	107	then
	108	nested_min=$nested
	109	fi
	110	done
	111	IFS=$oldIFS
	112
	113	debug_print "NESTED MIN: $nested_min"
	114
	115	while test "$nested_min" -gt "0"
	116	do
	117	start=$(( start + 1 ))
	118	end=$(( end - 1 ))
	119
	120	start_minus_one=$(( start - 1 ))
	121
	122	while ! test "$(substring "$LAYOUT" "$start_minus_one" 1)" = "("
	123	do
	124	start=$(( start + 1 ))
	125	start_minus_one=$(( start_minus_one + 1 ))
	126	done
	127
	128	while ! test "$(substring "$LAYOUT" "$end" 1)" = ")"
	129	do
	130	end=$(( end - 1 ))
	131	done
	132
	133	nested_min=$(( nested_min - 1 ))
	134	done
	135
	136	debug_print "CLEAN : $(substring "$LAYOUT" "$start" "$(( end - start ))")"
	137
	138
	139	# Step 2:
	140	#
	141	# Search for all valid separators ("/" or ",") which are not
	142	# inside parenthesis. Save the index at which each of them makes the
	143	# first appearance.
	144
	145	index_horizontal_split=""
	146	index_vertical_split=""
	147
	148	nested=0
	149	i=$(( start - 1 ))
	150
	151	oldIFS=$IFS
	152	IFS=#
	153	for c in $(substring "$LAYOUT" "$start" "$(( end - start ))" \| sed 's:.:&#:g');
	154	do
	155	i=$(( i + 1 ))
	156
	157	if test "$c" = " "
	158	then
	159	continue
	160	fi
	161
	162	if test "$c" = "("
	163	then
	164	nested=$(( nested + 1 ))
	165	continue
	166	fi
	167
	168	if test "$c" = ")"
	169	then
	170	nested=$(( nested - 1 ))
	171	continue
	172	fi
	173
	174	if test "$nested" = 0
	175	then
	176	current=$c
	177
	178	if test "$current" = "/"
	179	then
	180	if test -z "$index_horizontal_split"
	181	then
	182	index_horizontal_split=$i
	183	fi
	184
	185	elif test "$current" = ","
	186	then
	187	if test -z "$index_vertical_split"
	188	then
	189	index_vertical_split=$i
	190	fi
	191	fi
	192	fi
	193	done
	194	IFS=$oldIFS
	195
	196
	197	# Step 3:
	198	#
	199	# Process the separator with the highest order of precedence
	200	# (";" has the highest precedence and "\|" the lowest one).
	201	#
	202	# By "process" I mean recursively call this function twice: the first
	203	# one with the substring at the left of the separator and the second one
	204	# with the one at its right.
	205
	206	terminate="false"
	207
	208	if ! test -z "$index_horizontal_split"
	209	then
	210	before="leftabove split"
	211	after="wincmd j"
	212	index=$index_horizontal_split
	213	terminate="true"
	214
	215	elif ! test -z "$index_vertical_split"
	216	then
	217	before="leftabove vertical split"
	218	after="wincmd l"
	219	index=$index_vertical_split
	220	terminate="true"
	221	fi
	222
	223	if test "$terminate" = "true"
	224	then
	225	CMD="$CMD \| $before"
	226	CMD=$(gen_cmd_aux "$(substring "$LAYOUT" "$start" "$(( index - start ))")" "$CMD")
	227	CMD="$CMD \| $after"
	228	CMD=$(gen_cmd_aux "$(substring "$LAYOUT" "$(( index + 1 ))" "$(( ${#LAYOUT} - index ))")" "$CMD")
	229	echo "$CMD"
	230	return
	231	fi
	232
	233
	234	# Step 4:
	235	#
	236	# If we reach this point, it means there are no separators and we just
	237	# need to print the command to display the specified buffer
	238
	239	target=$(substring "$LAYOUT" "$start" "$(( end - start ))" \| sed 's:[ @();\|-]::g')
	240
	241	if test "$target" = "LOCAL"
	242	then
	243	CMD="$CMD \| 1b"
	244
	245	elif test "$target" = "BASE"
	246	then
	247	CMD="$CMD \| 2b"
	248
	249	elif test "$target" = "REMOTE"
	250	then
	251	CMD="$CMD \| 3b"
	252
	253	elif test "$target" = "MERGED"
	254	then
	255	CMD="$CMD \| 4b"
	256
	257	else
	258	CMD="$CMD \| ERROR: >$target<"
	259	fi
	260
	261	echo "$CMD"
	262	return
	263	}
	264
	265
	266	gen_cmd () {
	267	# This function returns (in global variable FINAL_CMD) the string that
	268	# you can use when invoking "vim" (as shown next) to obtain a given
	269	# layout:
	270	#
	271	# $ vim -f $FINAL_CMD "$LOCAL" "$BASE" "$REMOTE" "$MERGED"
	272	#
	273	# It takes one single argument: a string containing the desired layout
	274	# definition.
	275	#
	276	# The syntax of the "layout definitions" is explained in "Documentation/
	277	# mergetools/vimdiff.txt" but you can already intuitively understand how
	278	# it works by knowing that...
	279	#
	280	# * "+" means "a new vim tab"
	281	# * "/" means "a new vim horizontal split"
	282	# * "," means "a new vim vertical split"
	283	#
	284	# It also returns (in global variable FINAL_TARGET) the name ("LOCAL",
	285	# "BASE", "REMOTE" or "MERGED") of the file that is marked with an "@",
	286	# or "MERGED" if none of them is.
	287	#
	288	# Example:
	289	#
	290	# gen_cmd "@LOCAL , REMOTE"
	291	# \|
	292	# `-> FINAL_CMD == "-c \"echo \| leftabove vertical split \| 1b \| wincmd l \| 3b \| tabdo windo diffthis\" -c \"tabfirst\""
	293	# FINAL_TARGET == "LOCAL"
	294
	295	LAYOUT=$1
	296
	297
	298	# Search for a "@" in one of the files identifiers ("LOCAL", "BASE",
	299	# "REMOTE", "MERGED"). If not found, use "MERGE" as the default file
	300	# where changes will be saved.
	301
	302	if echo "$LAYOUT" \| grep @LOCAL >/dev/null
	303	then
	304	FINAL_TARGET="LOCAL"
	305	elif echo "$LAYOUT" \| grep @BASE >/dev/null
	306	then
	307	FINAL_TARGET="BASE"
	308	else
	309	FINAL_TARGET="MERGED"
	310	fi
	311
	312
	313	# Obtain the first part of vim "-c" option to obtain the desired layout
	314
	315	CMD=
	316	oldIFS=$IFS
	317	IFS=+
	318	for tab in $LAYOUT
	319	do
	320	if test -z "$CMD"
	321	then
	322	CMD="echo" # vim "nop" operator
	323	else
	324	CMD="$CMD \| tabnew"
	325	fi
	326
	327	# If this is a single window diff with all the buffers
	328	if ! echo "$tab" \| grep ",\\|/" >/dev/null
	329	then
	330	CMD="$CMD \| silent execute 'bufdo diffthis'"
	331	fi
	332
	333	CMD=$(gen_cmd_aux "$tab" "$CMD")
	334	done
	335	IFS=$oldIFS
	336
	337	CMD="$CMD \| execute 'tabdo windo diffthis'"
	338
	339	FINAL_CMD="-c \"set hidden diffopt-=hiddenoff \| $CMD \| tabfirst\""
	340	}
	341
	342
	343	################################################################################
	344	## API functions (called from "git-mergetool--lib.sh")
	345	################################################################################
	346
	347	diff_cmd () {
	348	"$merge_tool_path" -R -f -d \
	349	-c 'wincmd l' -c 'cd $GIT_PREFIX' "$LOCAL" "$REMOTE"
	350	}
	351
	352
	353	diff_cmd_help () {
	354	TOOL=$1
	355
	356	case "$TOOL" in
	357	nvimdiff*)
	358	printf "Use Neovim"
	359	;;
	360	gvimdiff*)
	361	printf "Use gVim (requires a graphical session)"
	362	;;
	363	vimdiff*)
	364	printf "Use Vim"
	365	;;
	366	esac
	367
	368	return 0
	369	}
	370
	371
	372	merge_cmd () {
	373	TOOL=$1
	374
	375	layout=$(git config "mergetool.$TOOL.layout")
	376
	377	# backward compatibility:
	378	if test -z "$layout"
	379	then
	380	layout=$(git config mergetool.vimdiff.layout)
	381	fi
	382
	383	case "$TOOL" in
	384	*vimdiff)
	385	if test -z "$layout"
	386	then
	387	# Default layout when none is specified
	388	layout="(LOCAL,BASE,REMOTE)/MERGED"
	389	fi
	390	;;
	391	*vimdiff1)
	392	layout="@LOCAL,REMOTE"
	393	;;
	394	*vimdiff2)
	395	layout="LOCAL,MERGED,REMOTE"
	396	;;
	397	*vimdiff3)
	398	layout="MERGED"
	399	;;
	400	esac
	401
	402	gen_cmd "$layout"
	403
	404	debug_print ""
	405	debug_print "FINAL CMD : $FINAL_CMD"
	406	debug_print "FINAL TAR : $FINAL_TARGET"
	407
	408	if $base_present
	409	then
	410	eval '"$merge_tool_path"' \
	411	-f "$FINAL_CMD" '"$LOCAL"' '"$BASE"' '"$REMOTE"' '"$MERGED"'
	412	else
	413	# If there is no BASE (example: a merge conflict in a new file
	414	# with the same name created in both braches which didn't exist
	415	# before), close all BASE windows using vim's "quit" command
	416
	417	FINAL_CMD=$(echo "$FINAL_CMD" \| \
	418	sed -e 's:2b:quit:g' -e 's:3b:2b:g' -e 's:4b:3b:g')
	419
	420	eval '"$merge_tool_path"' \
	421	-f "$FINAL_CMD" '"$LOCAL"' '"$REMOTE"' '"$MERGED"'
	422	fi
	423
	424	ret="$?"
	425
	426	if test "$ret" -eq 0
	427	then
	428	case "$FINAL_TARGET" in
	429	LOCAL)
	430	source_path="$LOCAL"
	431	;;
	432	REMOTE)
	433	source_path="$REMOTE"
	434	;;
	435	MERGED\|*)
	436	# Do nothing
	437	source_path=
	438	;;
	439	esac
	440
	441	if test -n "$source_path"
	442	then
	443	cp "$source_path" "$MERGED"
	444	fi
	445	fi
	446
	447	return "$ret"
	448	}
	449
	450
	451	merge_cmd_help () {
	452	TOOL=$1
	453
	454	case "$TOOL" in
	455	nvimdiff*)
	456	printf "Use Neovim "
	457	;;
	458	gvimdiff*)
	459	printf "Use gVim (requires a graphical session) "
	460	;;
	461	vimdiff*)
	462	printf "Use Vim "
	463	;;
	464	esac
	465
	466	case "$TOOL" in
	467	*1)
	468	echo "with a 2 panes layout (LOCAL and REMOTE)"
	469	;;
	470	*2)
	471	echo "with a 3 panes layout (LOCAL, MERGED and REMOTE)"
	472	;;
	473	*3)
	474	echo "where only the MERGED file is shown"
	475	;;
	476	*)
	477	echo "with a custom layout (see \`git help mergetool\`'s \`BACKEND SPECIFIC HINTS\` section)"
	478	;;
	479	esac
	480
	481	return 0
	482	}
	483
	484
	485	translate_merge_tool_path () {
	486	case "$1" in
	487	nvimdiff*)
	488	echo nvim
	489	;;
	490	gvimdiff*)
	491	echo gvim
	492	;;
	493	vimdiff*)
	494	echo vim
	495	;;
	496	esac
	497	}
	498
	499
	500	exit_code_trustable () {
	501	true
	502	}
	503
	504
	505	list_tool_variants () {
	506	if test "$TOOL_MODE" = "diff"
	507	then
	508	for prefix in '' g n
	509	do
	510	echo "${prefix}vimdiff"
	511	done
	512	else
	513	for prefix in '' g n
	514	do
	515	for suffix in '' 1 2 3
	516	do
	517	echo "${prefix}vimdiff${suffix}"
	518	done
	519	done
	520	fi
	521	}
	522
	523
	524	################################################################################
	525	## Unit tests (called from scripts inside the "t" folder)
	526	################################################################################
	527
	528	run_unit_tests () {
	529	# Function to make sure that we don't break anything when modifying this
	530	# script.
	531
	532	NUMBER_OF_TEST_CASES=16
	533
	534	TEST_CASE_01="(LOCAL,BASE,REMOTE)/MERGED" # default behaviour
	535	TEST_CASE_02="@LOCAL,REMOTE" # when using vimdiff1
	536	TEST_CASE_03="LOCAL,MERGED,REMOTE" # when using vimdiff2
	537	TEST_CASE_04="MERGED" # when using vimdiff3
	538	TEST_CASE_05="LOCAL/MERGED/REMOTE"
	539	TEST_CASE_06="(LOCAL/REMOTE),MERGED"
	540	TEST_CASE_07="MERGED,(LOCAL/REMOTE)"
	541	TEST_CASE_08="(LOCAL,REMOTE)/MERGED"
	542	TEST_CASE_09="MERGED/(LOCAL,REMOTE)"
	543	TEST_CASE_10="(LOCAL/BASE/REMOTE),MERGED"
	544	TEST_CASE_11="(LOCAL,BASE,REMOTE)/MERGED+BASE,LOCAL+BASE,REMOTE+(LOCAL/BASE/REMOTE),MERGED"
	545	TEST_CASE_12="((LOCAL,REMOTE)/BASE),MERGED"
	546	TEST_CASE_13="((LOCAL,REMOTE)/BASE),((LOCAL/REMOTE),MERGED)"
	547	TEST_CASE_14="BASE,REMOTE+BASE,LOCAL"
	548	TEST_CASE_15=" (( (LOCAL , BASE , REMOTE) / MERGED)) +(BASE) , LOCAL+ BASE , REMOTE+ (((LOCAL / BASE / REMOTE)) , MERGED ) "
	549	TEST_CASE_16="LOCAL,BASE,REMOTE / MERGED + BASE,LOCAL + BASE,REMOTE + (LOCAL / BASE / REMOTE),MERGED"
	550
	551	EXPECTED_CMD_01="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| leftabove vertical split \| 2b \| wincmd l \| 3b \| wincmd j \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	552	EXPECTED_CMD_02="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| 1b \| wincmd l \| 3b \| execute 'tabdo windo diffthis' \| tabfirst\""
	553	EXPECTED_CMD_03="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| 1b \| wincmd l \| leftabove vertical split \| 4b \| wincmd l \| 3b \| execute 'tabdo windo diffthis' \| tabfirst\""
	554	EXPECTED_CMD_04="-c \"set hidden diffopt-=hiddenoff \| echo \| silent execute 'bufdo diffthis' \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	555	EXPECTED_CMD_05="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| 1b \| wincmd j \| leftabove split \| 4b \| wincmd j \| 3b \| execute 'tabdo windo diffthis' \| tabfirst\""
	556	EXPECTED_CMD_06="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| leftabove split \| 1b \| wincmd j \| 3b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	557	EXPECTED_CMD_07="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| 4b \| wincmd l \| leftabove split \| 1b \| wincmd j \| 3b \| execute 'tabdo windo diffthis' \| tabfirst\""
	558	EXPECTED_CMD_08="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| 3b \| wincmd j \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	559	EXPECTED_CMD_09="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| 4b \| wincmd j \| leftabove vertical split \| 1b \| wincmd l \| 3b \| execute 'tabdo windo diffthis' \| tabfirst\""
	560	EXPECTED_CMD_10="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| leftabove split \| 1b \| wincmd j \| leftabove split \| 2b \| wincmd j \| 3b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	561	EXPECTED_CMD_11="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| leftabove vertical split \| 2b \| wincmd l \| 3b \| wincmd j \| 4b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 1b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 3b \| tabnew \| leftabove vertical split \| leftabove split \| 1b \| wincmd j \| leftabove split \| 2b \| wincmd j \| 3b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	562	EXPECTED_CMD_12="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| 3b \| wincmd j \| 2b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	563	EXPECTED_CMD_13="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| 3b \| wincmd j \| 2b \| wincmd l \| leftabove vertical split \| leftabove split \| 1b \| wincmd j \| 3b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	564	EXPECTED_CMD_14="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove vertical split \| 2b \| wincmd l \| 3b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 1b \| execute 'tabdo windo diffthis' \| tabfirst\""
	565	EXPECTED_CMD_15="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| leftabove vertical split \| 2b \| wincmd l \| 3b \| wincmd j \| 4b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 1b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 3b \| tabnew \| leftabove vertical split \| leftabove split \| 1b \| wincmd j \| leftabove split \| 2b \| wincmd j \| 3b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	566	EXPECTED_CMD_16="-c \"set hidden diffopt-=hiddenoff \| echo \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| leftabove vertical split \| 2b \| wincmd l \| 3b \| wincmd j \| 4b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 1b \| tabnew \| leftabove vertical split \| 2b \| wincmd l \| 3b \| tabnew \| leftabove vertical split \| leftabove split \| 1b \| wincmd j \| leftabove split \| 2b \| wincmd j \| 3b \| wincmd l \| 4b \| execute 'tabdo windo diffthis' \| tabfirst\""
	567
	568	EXPECTED_TARGET_01="MERGED"
	569	EXPECTED_TARGET_02="LOCAL"
	570	EXPECTED_TARGET_03="MERGED"
	571	EXPECTED_TARGET_04="MERGED"
	572	EXPECTED_TARGET_05="MERGED"
	573	EXPECTED_TARGET_06="MERGED"
	574	EXPECTED_TARGET_07="MERGED"
	575	EXPECTED_TARGET_08="MERGED"
	576	EXPECTED_TARGET_09="MERGED"
	577	EXPECTED_TARGET_10="MERGED"
	578	EXPECTED_TARGET_11="MERGED"
	579	EXPECTED_TARGET_12="MERGED"
	580	EXPECTED_TARGET_13="MERGED"
	581	EXPECTED_TARGET_14="MERGED"
	582	EXPECTED_TARGET_15="MERGED"
	583	EXPECTED_TARGET_16="MERGED"
	584
	585	at_least_one_ko="false"
	586
	587	for i in $(seq -w 1 99)
	588	do
	589	if test "$i" -gt $NUMBER_OF_TEST_CASES
	590	then
	591	break
	592	fi
	593
	594	gen_cmd "$(eval echo \${TEST_CASE_"$i"})"
	595
	596	if test "$FINAL_CMD" = "$(eval echo \${EXPECTED_CMD_"$i"})" \
	597	&& test "$FINAL_TARGET" = "$(eval echo \${EXPECTED_TARGET_"$i"})"
	598	then
	599	printf "Test Case #%02d: OK\n" "$(echo "$i" \| sed 's/^0*//')"
	600	else
	601	printf "Test Case #%02d: KO !!!!\n" "$(echo "$i" \| sed 's/^0*//')"
	602	echo " FINAL_CMD : $FINAL_CMD"
	603	echo " FINAL_CMD (expected) : $(eval echo \${EXPECTED_CMD_"$i"})"
	604	echo " FINAL_TARGET : $FINAL_TARGET"
	605	echo " FINAL_TARGET (expected): $(eval echo \${EXPECTED_TARGET_"$i"})"
	606	at_least_one_ko="true"
	607	fi
	608	done
	609
	610	# verify that `merge_cmd` handles paths with spaces
	611	record_parameters () {
	612	>actual
	613	for arg
	614	do
	615	echo "$arg" >>actual
	616	done
	617	}
	618
	619	base_present=false
	620	LOCAL='lo cal'
	621	BASE='ba se'
	622	REMOTE="' '"
	623	MERGED='mer ged'
	624	merge_tool_path=record_parameters
	625
	626	merge_cmd vimdiff \|\| at_least_one_ko=true
	627
	628	cat >expect <<-\EOF
	629	-f
	630	-c
	631	set hidden diffopt-=hiddenoff \| echo \| leftabove split \| leftabove vertical split \| 1b \| wincmd l \| leftabove vertical split \| quit \| wincmd l \| 2b \| wincmd j \| 3b \| execute 'tabdo windo diffthis' \| tabfirst
	632	lo cal
	633	' '
	634	mer ged
	635	EOF
	636
	637	diff -u expect actual \|\| at_least_one_ko=true
	638
	639	if test "$at_least_one_ko" = "true"
	640	then
	641	return 255
	642	else
	643	return 0
	644	fi
	645	}