Hi brian

I agree with everything Elijah said, I just have one more comment

quoted

@@ -80,12 +88,21 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)

                 fname = prefix_filename(prefix, argv[i]);

-               if (read_mmfile(mmf, fname))
+               if (object_id) {
+                       if (repo_get_oid(the_repository, argv[i], &oid))
+                               ret = -1;

It would be nice to print an error message here

	ret = error("object '%s' does not exist", argv[i]);

none of the existing error messages are marked for translation so I've 
left this untranslated as well.

Best Wishes

Phillip