Merge branch 'da/mergetool-diff-order'

"git mergetool" learned to honor "-O<orderfile>" to control the
order of paths to present to the end user.

* da/mergetool-diff-order:
  mergetool: honor -O<orderfile>
  mergetool: honor diff.orderFile
  mergetool: move main program flow into a main() function
  mergetool: add copyright

Documentation/git-mergetool.txt

@@ -79,6 +79,13 @@ success of the resolution after the custom tool has exited.
 	Prompt before each invocation of the merge resolution program
 	to give the user a chance to skip the path.
 
+-O<orderfile>::
+	Process files in the order specified in the
+	<orderfile>, which has one shell glob pattern per line.
+	This overrides the `diff.orderFile` configuration variable
+	(see linkgit:git-config[1]).  To cancel `diff.orderFile`,
+	use `-O/dev/null`.
+
 TEMPORARY FILES
 ---------------
 `git mergetool` creates `*.orig` backup files while resolving merges.

git-mergetool.sh

@@ -3,12 +3,13 @@
 # This program resolves merge conflicts in git
 #
 # Copyright (c) 2006 Theodore Y. Ts'o
+# Copyright (c) 2009-2016 David Aguilar
 #
 # This file is licensed under the GPL v2, or a later version
 # at the discretion of Junio C Hamano.
 #
 
-USAGE='[--tool=tool] [--tool-help] [-y|--no-prompt|--prompt] [file to merge] ...'
+USAGE='[--tool=tool] [--tool-help] [-y|--no-prompt|--prompt] [-O<orderfile>] [file to merge] ...'
 SUBDIRECTORY_OK=Yes
 NONGIT_OK=Yes
 OPTIONS_SPEC=
@@ -365,51 +366,6 @@ merge_file () {
 	return 0
 }
 
-prompt=$(git config --bool mergetool.prompt)
-guessed_merge_tool=false
-
-while test $# != 0
-do
-	case "$1" in
-	--tool-help=*)
-		TOOL_MODE=${1#--tool-help=}
-		show_tool_help
-		;;
-	--tool-help)
-		show_tool_help
-		;;
-	-t|--tool*)
-		case "$#,$1" in
-		*,*=*)
-			merge_tool=$(expr "z$1" : 'z-[^=]*=\(.*\)')
-			;;
-		1,*)
-			usage ;;
-		*)
-			merge_tool="$2"
-			shift ;;
-		esac
-		;;
-	-y|--no-prompt)
-		prompt=false
-		;;
-	--prompt)
-		prompt=true
-		;;
-	--)
-		shift
-		break
-		;;
-	-*)
-		usage
-		;;
-	*)
-		break
-		;;
-	esac
-	shift
-done
-
 prompt_after_failed_merge () {
 	while true
 	do
@@ -426,57 +382,113 @@ prompt_after_failed_merge () {
 	done
 }
 
-git_dir_init
+print_noop_and_exit () {
-require_work_tree
-
-if test -z "$merge_tool"
-then
-	# Check if a merge tool has been configured
-	merge_tool=$(get_configured_merge_tool)
-	# Try to guess an appropriate merge tool if no tool has been set.
-	if test -z "$merge_tool"
-	then
-		merge_tool=$(guess_merge_tool) || exit
-		guessed_merge_tool=true
-	fi
-fi
-merge_keep_backup="$(git config --bool mergetool.keepBackup || echo true)"
-merge_keep_temporaries="$(git config --bool mergetool.keepTemporaries || echo false)"
-
-files=
-
-if test $# -eq 0
-then
-	cd_to_toplevel
-
-	if test -e "$GIT_DIR/MERGE_RR"
-	then
-		files=$(git rerere remaining)
-	else
-		files=$(git ls-files -u | sed -e 's/^[^	]*	//' | sort -u)
-	fi
-else
-	files=$(git ls-files -u -- "$@" | sed -e 's/^[^	]*	//' | sort -u)
-fi
-
-if test -z "$files"
-then
 	echo "No files need merging"
 	exit 0
-fi
+}
 
-printf "Merging:\n"
+main () {
-printf "%s\n" "$files"
+	prompt=$(git config --bool mergetool.prompt)
+	guessed_merge_tool=false
+	orderfile=
 
-rc=0
+	while test $# != 0
-for i in $files
+	do
-do
+		case "$1" in
-	printf "\n"
+		--tool-help=*)
-	if ! merge_file "$i"
+			TOOL_MODE=${1#--tool-help=}
+			show_tool_help
+			;;
+		--tool-help)
+			show_tool_help
+			;;
+		-t|--tool*)
+			case "$#,$1" in
+			*,*=*)
+				merge_tool=$(expr "z$1" : 'z-[^=]*=\(.*\)')
+				;;
+			1,*)
+				usage ;;
+			*)
+				merge_tool="$2"
+				shift ;;
+			esac
+			;;
+		-y|--no-prompt)
+			prompt=false
+			;;
+		--prompt)
+			prompt=true
+			;;
+		-O*)
+			orderfile="$1"
+			;;
+		--)
+			shift
+			break
+			;;
+		-*)
+			usage
+			;;
+		*)
+			break
+			;;
+		esac
+		shift
+	done
+
+	git_dir_init
+	require_work_tree
+
+	if test -z "$merge_tool"
 	then
-		rc=1
+		# Check if a merge tool has been configured
-		prompt_after_failed_merge || exit 1
+		merge_tool=$(get_configured_merge_tool)
+		# Try to guess an appropriate merge tool if no tool has been set.
+		if test -z "$merge_tool"
+		then
+			merge_tool=$(guess_merge_tool) || exit
+			guessed_merge_tool=true
+		fi
 	fi
-done
+	merge_keep_backup="$(git config --bool mergetool.keepBackup || echo true)"
+	merge_keep_temporaries="$(git config --bool mergetool.keepTemporaries || echo false)"
 
-exit $rc
+	if test $# -eq 0 && test -e "$GIT_DIR/MERGE_RR"
+	then
+		set -- $(git rerere remaining)
+		if test $# -eq 0
+		then
+			print_noop_and_exit
+		fi
+	fi
+
+	files=$(git -c core.quotePath=false \
+		diff --name-only --diff-filter=U \
+		${orderfile:+"$orderfile"} -- "$@")
+
+	cd_to_toplevel
+
+	if test -z "$files"
+	then
+		print_noop_and_exit
+	fi
+
+	printf "Merging:\n"
+	printf "%s\n" "$files"
+
+	rc=0
+	for i in $files
+	do
+		printf "\n"
+		if ! merge_file "$i"
+		then
+			rc=1
+			prompt_after_failed_merge || exit 1
+		fi
+	done
+
+	exit $rc
+}
+
+main "$@"

t/t7610-mergetool.sh

@@ -606,4 +606,64 @@ test_expect_success MKTEMP 'temporary filenames are used with mergetool.writeToT
 	git reset --hard master >/dev/null 2>&1
 '
 
+test_expect_success 'diff.orderFile configuration is honored' '
+	test_config diff.orderFile order-file &&
+	test_config mergetool.myecho.cmd "echo \"\$LOCAL\"" &&
+	test_config mergetool.myecho.trustExitCode true &&
+	echo b >order-file &&
+	echo a >>order-file &&
+	git checkout -b order-file-start master &&
+	echo start >a &&
+	echo start >b &&
+	git add a b &&
+	git commit -m start &&
+	git checkout -b order-file-side1 order-file-start &&
+	echo side1 >a &&
+	echo side1 >b &&
+	git add a b &&
+	git commit -m side1 &&
+	git checkout -b order-file-side2 order-file-start &&
+	echo side2 >a &&
+	echo side2 >b &&
+	git add a b &&
+	git commit -m side2 &&
+	test_must_fail git merge order-file-side1 &&
+	cat >expect <<-\EOF &&
+		Merging:
+		b
+		a
+	EOF
+	git mergetool --no-prompt --tool myecho >output &&
+	git grep --no-index -h -A2 Merging: output >actual &&
+	test_cmp expect actual &&
+	git reset --hard >/dev/null
+'
+test_expect_success 'mergetool -Oorder-file is honored' '
+	test_config diff.orderFile order-file &&
+	test_config mergetool.myecho.cmd "echo \"\$LOCAL\"" &&
+	test_config mergetool.myecho.trustExitCode true &&
+	test_must_fail git merge order-file-side1 &&
+	cat >expect <<-\EOF &&
+		Merging:
+		a
+		b
+	EOF
+	git mergetool -O/dev/null --no-prompt --tool myecho >output &&
+	git grep --no-index -h -A2 Merging: output >actual &&
+	test_cmp expect actual &&
+	git reset --hard >/dev/null 2>&1 &&
+
+	git config --unset diff.orderFile &&
+	test_must_fail git merge order-file-side1 &&
+	cat >expect <<-\EOF &&
+		Merging:
+		b
+		a
+	EOF
+	git mergetool -Oorder-file --no-prompt --tool myecho >output &&
+	git grep --no-index -h -A2 Merging: output >actual &&
+	test_cmp expect actual &&
+	git reset --hard >/dev/null 2>&1
+'
+
 test_done