subtree: add 'die_incompatible_opt' function to reduce duplication

9a3e3ca (subtree: be stricter about validating flags, 2021-04-27)
added validation code to check that options given to 'git subtree <cmd>'
made sense with the command being used.

Refactor these checks by adding a 'die_incompatible_opt' function to
reduce code duplication.

Signed-off-by: Philippe Blain <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: phil-blain

contrib/subtree/git-subtree.sh

@@ -102,6 +102,14 @@ assert () {
 	fi
 }
 
+# Usage: die_incompatible_opt OPTION COMMAND
+die_incompatible_opt () {
+	assert test "$#" = 2
+	opt="$1"
+	arg_command="$2"
+	die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+}
+
 main () {
 	if test $# -eq 0
 	then
@@ -176,16 +184,16 @@ main () {
 			arg_debug=1
 			;;
 		--annotate)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_annotate="$1"
 			shift
 			;;
 		--no-annotate)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_annotate=
 			;;
 		-b)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_branch="$1"
 			shift
 			;;
@@ -194,42 +202,42 @@ main () {
 			shift
 			;;
 		-m)
-			test -n "$allow_addmerge" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_addmerge" || die_incompatible_opt "$opt" "$arg_command"
 			arg_addmerge_message="$1"
 			shift
 			;;
 		--no-prefix)
 			arg_prefix=
 			;;
 		--onto)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_onto="$1"
 			shift
 			;;
 		--no-onto)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_onto=
 			;;
 		--rejoin)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			;;
 		--no-rejoin)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			;;
 		--ignore-joins)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_ignore_joins=1
 			;;
 		--no-ignore-joins)
-			test -n "$allow_split" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_split" || die_incompatible_opt "$opt" "$arg_command"
 			arg_split_ignore_joins=
 			;;
 		--squash)
-			test -n "$allow_addmerge" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_addmerge" || die_incompatible_opt "$opt" "$arg_command"
 			arg_addmerge_squash=1
 			;;
 		--no-squash)
-			test -n "$allow_addmerge" || die "The '$opt' flag does not make sense with 'git subtree $arg_command'."
+			test -n "$allow_addmerge" || die_incompatible_opt "$opt" "$arg_command"
 			arg_addmerge_squash=
 			;;
 		--)