format-patch: allow --range-diff to apply to a lone-patch

diff --git a/builtin/log.c b/builtin/log.c
index 05965a57ca6ea43a3de19283d278051120d75697..f69b67b9cef050e1e5506d2b3a9f7c1f9c519a18 100644 (file)
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1576,7 +1576,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                             N_("show changes against <rev> in cover letter or single patch"),
                             parse_opt_object_name),
                OPT_STRING(0, "range-diff", &rdiff_prev, N_("refspec"),
-                          N_("show changes against <refspec> in cover letter")),
+                          N_("show changes against <refspec> in cover letter or single patch")),
                OPT_INTEGER(0, "creation-factor", &creation_factor,
                            N_("percentage by which creation is weighted")),
                OPT_END()
@@ -1817,8 +1817,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                die(_("--creation-factor requires --range-diff"));
 
        if (rdiff_prev) {
-               if (!cover_letter)
-                       die(_("--range-diff requires --cover-letter"));
+               if (!cover_letter && total != 1)
+                       die(_("--range-diff requires --cover-letter or single patch"));
 
                infer_range_diff_ranges(&rdiff1, &rdiff2, rdiff_prev,
                                        origin, list[0]);
@@ -1867,8 +1867,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                print_signature(rev.diffopt.file);
                total++;
                start_number--;
-               /* interdiff in cover-letter; omit from patches */
+               /* interdiff/range-diff in cover-letter; omit from patches */
                rev.idiff_oid1 = NULL;
+               rev.rdiff1 = NULL;
        }
        rev.add_signoff = do_signoff;