diff-parseopt: convert -C|--find-copies

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff.c

@@ -4617,8 +4617,6 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
 	return 1;
 }
 
-static int diff_scoreopt_parse(const char *opt);
-
 static inline int short_opt(char opt, const char **argv,
 			    const char **optarg)
 {
@@ -4909,6 +4907,26 @@ static int diff_opt_dirstat(const struct option *opt,
 	return 0;
 }
 
+static int diff_opt_find_copies(const struct option *opt,
+				const char *arg, int unset)
+{
+	struct diff_options *options = opt->value;
+
+	BUG_ON_OPT_NEG(unset);
+	if (!arg)
+		arg = "";
+	options->rename_score = parse_rename_score(&arg);
+	if (*arg != 0)
+		return error(_("invalid argument to %s"), opt->long_name);
+
+	if (options->detect_rename == DIFF_DETECT_COPY)
+		options->flags.find_copies_harder = 1;
+	else
+		options->detect_rename = DIFF_DETECT_COPY;
+
+	return 0;
+}
+
 static int diff_opt_find_renames(const struct option *opt,
 				 const char *arg, int unset)
 {
@@ -5063,6 +5081,10 @@ static void prep_parse_options(struct diff_options *options)
 		OPT_SET_INT_F('D', "irreversible-delete", &options->irreversible_delete,
 			      N_("omit the preimage for deletes"),
 			      1, PARSE_OPT_NONEG),
+		OPT_CALLBACK_F('C', "find-copies", options, N_("<n>"),
+			       N_("detect copies"),
+			       PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+			       diff_opt_find_copies),
 
 		OPT_GROUP(N_("Diff other options")),
 		{ OPTION_CALLBACK, 0, "output", options, N_("<file>"),
@@ -5097,15 +5119,7 @@ int diff_opt_parse(struct diff_options *options,
 		return ac;
 
 	/* renames options */
-	if (starts_with(arg, "-C") ||
-		 skip_to_optional_arg(arg, "--find-copies", NULL)) {
-		if (options->detect_rename == DIFF_DETECT_COPY)
-			options->flags.find_copies_harder = 1;
-		if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
-			return error("invalid argument to -C: %s", arg+2);
-		options->detect_rename = DIFF_DETECT_COPY;
-	}
-	else if (!strcmp(arg, "--no-renames"))
+	if (!strcmp(arg, "--no-renames"))
 		options->detect_rename = 0;
 	else if (!strcmp(arg, "--rename-empty"))
 		options->flags.rename_empty = 1;
@@ -5365,29 +5379,6 @@ int parse_rename_score(const char **cp_p)
 	return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
 }
 
-static int diff_scoreopt_parse(const char *opt)
-{
-	int opt1, cmd;
-
-	if (*opt++ != '-')
-		return -1;
-	cmd = *opt++;
-	if (cmd == '-') {
-		/* convert the long-form arguments into short-form versions */
-		if (skip_prefix(opt, "find-copies", &opt)) {
-			if (*opt == 0 || *opt++ == '=')
-				cmd = 'C';
-		}
-	}
-	if (cmd != 'C')
-		return -1; /* that is not a -M option */
-
-	opt1 = parse_rename_score(&opt);
-	if (*opt != 0)
-		return -1;
-	return opt1;
-}
-
 struct diff_queue_struct diff_queued_diff;
 
 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)