-static char *diff_tree_usage =
-"git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-O<orderfile>] [-m] [-s] [-v] [--pretty] [-t] <tree-ish> <tree-ish>";
-
-static enum cmit_fmt get_commit_format(const char *arg)
-{
- if (!*arg)
- return CMIT_FMT_DEFAULT;
- if (!strcmp(arg, "=raw"))
- return CMIT_FMT_RAW;
- if (!strcmp(arg, "=medium"))
- return CMIT_FMT_MEDIUM;
- if (!strcmp(arg, "=short"))
- return CMIT_FMT_SHORT;
- usage(diff_tree_usage);
-}
+static const char diff_tree_usage[] =
+"git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] "
+"[<common diff options>] <tree-ish> <tree-ish>"
+COMMON_DIFF_OPTIONS_HELP;