diff: report bogus input to -C/-M/-B

We already detect invalid input to these functions, but we simply exit with an error code, never saying anything as simple as "your input was wrong". Let's fix that. Before: $ git diff -CM $ echo $? 128 After: $ git diff -CM error: invalid argument to -C: M $ echo $? 128 There should be no problems with having diff_opt_parse print to stderr, as there is already precedent in complaining about bogus --color and --output arguments. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Oct 21, 2010 at 10:49 UTC 07cd7265274ba6aed2589e6b22eae7d413640037

1 file changed +3 -3

diff.c

+3 -3

@@ -3142,18 +3142,18 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)

3142 /* renames options */

3143 else if (!prefixcmp(arg, "-B")) {

3144 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)

3145 - return -1;

3145 + return error("invalid argument to -B: %s", arg+2);

3146 }

3147 else if (!prefixcmp(arg, "-M")) {

3148 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)

3149 - return -1;

3149 + return error("invalid argument to -M: %s", arg+2);

3150 options->detect_rename = DIFF_DETECT_RENAME;

3151 }

3152 else if (!prefixcmp(arg, "-C")) {

3153 if (options->detect_rename == DIFF_DETECT_COPY)

3154 DIFF_OPT_SET(options, FIND_COPIES_HARDER);

3155 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)

3156 - return -1;

3156 + return error("invalid argument to -C: %s", arg+2);

3157 options->detect_rename = DIFF_DETECT_COPY;

3158 }

3159 else if (!strcmp(arg, "--no-renames"))