t/perf: add perf script for partial clones

diff --git a/range-diff.c b/range-diff.c
index 3958720f004ebe9ba027cd6097a7cd3ce41e3d73..48b0e1b4ce0ff69b9c7a430174db25b1ca6494f8 100644 (file)
--- a/range-diff.c
+++ b/range-diff.c
@@ -460,8 +460,13 @@ int show_range_diff(const char *range1, const char *range2,
                struct diff_options opts;
                struct strbuf indent = STRBUF_INIT;
 
-               memcpy(&opts, diffopt, sizeof(opts));
-               opts.output_format = DIFF_FORMAT_PATCH;
+               if (diffopt)
+                       memcpy(&opts, diffopt, sizeof(opts));
+               else
+                       diff_setup(&opts);
+
+               if (!opts.output_format)
+                       opts.output_format = DIFF_FORMAT_PATCH;
                opts.flags.suppress_diff_headers = 1;
                opts.flags.dual_color_diffed_diffs = dual_color;
                opts.output_prefix = output_prefix_cb;