diff-parseopt: convert --[no-]minimal

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

diff.c

@@ -5105,6 +5105,11 @@ static void prep_parse_options(struct diff_options *options)
 		OPT_BOOL(0, "rename-empty", &options->flags.rename_empty,
 			 N_("use empty blobs as rename source")),
 
+		OPT_GROUP(N_("Diff algorithm options")),
+		OPT_BIT(0, "minimal", &options->xdl_opts,
+			N_("produce the smallest possible diff"),
+			XDF_NEED_MINIMAL),
+
 		OPT_GROUP(N_("Diff other options")),
 		OPT_CALLBACK_F(0, "relative", options, N_("<prefix>"),
 			       N_("when run from subdir, exclude changes outside and show relative paths"),
@@ -5142,11 +5147,7 @@ int diff_opt_parse(struct diff_options *options,
 		return ac;
 
 	/* xdiff options */
-	if (!strcmp(arg, "--minimal"))
-		DIFF_XDL_SET(options, NEED_MINIMAL);
-	else if (!strcmp(arg, "--no-minimal"))
-		DIFF_XDL_CLR(options, NEED_MINIMAL);
-	else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
+	if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
 		DIFF_XDL_SET(options, IGNORE_WHITESPACE);
 	else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
 		DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);