Merge branch 'jc/fix-diff-no-index-diff-opt-parse' into maint

* jc/fix-diff-no-index-diff-opt-parse:
diff-no-index: correctly diagnose error return from diff_opt_parse()

diff --combined diff-no-index.c
index 33e5982a1c61a5726580f40df0a07dadc7e2aaf1,ecf929336d0c8d40862ad88ac188f5e18166c9f9..798477f7e5b19e3141bd8a1e63bc650f13ad2e39
--- 1/diff-no-index.c
--- 2/diff-no-index.c
+++ b/diff-no-index.c
@@@ -183,12 -183,54 +183,12 @@@ static int queue_diff(struct diff_optio
  
  void diff_no_index(struct rev_info *revs,
                   int argc, const char **argv,
 -                 int nongit, const char *prefix)
 +                 const char *prefix)
  {
        int i, prefixlen;
 -      int no_index = 0;
        unsigned deprecated_show_diff_q_option_used = 0;
        const char *paths[2];
  
 -      /* Were we asked to do --no-index explicitly? */
 -      for (i = 1; i < argc; i++) {
 -              if (!strcmp(argv[i], "--")) {
 -                      i++;
 -                      break;
 -              }
 -              if (!strcmp(argv[i], "--no-index"))
 -                      no_index = 1;
 -              if (argv[i][0] != '-')
 -                      break;
 -      }
 -
 -      if (!no_index && !nongit) {
 -              /*
 -               * Inside a git repository, without --no-index.  Only
 -               * when a path outside the repository is given,
 -               * e.g. "git diff /var/tmp/[12]", or "git diff
 -               * Makefile /var/tmp/Makefile", allow it to be used as
 -               * a colourful "diff" replacement.
 -               */
 -              if ((argc != i + 2) ||
 -                  (path_inside_repo(prefix, argv[i]) &&
 -                   path_inside_repo(prefix, argv[i+1])))
 -                      return;
 -      }
 -      if (argc != i + 2) {
 -              if (!no_index) {
 -                      /*
 -                       * There was no --no-index and there were not two
 -                       * paths. It is possible that the user intended
 -                       * to do an inside-repository operation.
 -                       */
 -                      fprintf(stderr, "Not a git repository\n");
 -                      fprintf(stderr,
 -                              "To compare two paths outside a working tree:\n");
 -              }
 -              /* Give the usage message for non-repository usage and exit. */
 -              usagef("git diff %s <path> <path>",
 -                     no_index ? "--no-index" : "[--no-index]");
 -      }
 -
        diff_setup(&revs->diffopt);
        for (i = 1; i < argc - 2; ) {
                int j;
@@@ -202,7 -244,7 +202,7 @@@
                        i++;
                else {
                        j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
-                       if (!j)
+                       if (j <= 0)
                                die("invalid diff option/value: %s", argv[i]);
                        i += j;
                }