diff --follow: do not waste cycles while recursing

diff --git a/tree-diff.c b/tree-diff.c
index fe9f52c4796512f40869e511b55a2d97fa84532e..5b68c0864cac22d083228d5966487913df5c6be2 100644 (file)
--- a/tree-diff.c
+++ b/tree-diff.c
@@ -346,7 +346,7 @@ static void try_to_follow_renames(struct tree_desc *t1, struct tree_desc *t2, co
 
        diff_setup(&diff_opts);
        DIFF_OPT_SET(&diff_opts, RECURSIVE);
-       diff_opts.detect_rename = DIFF_DETECT_RENAME;
+       DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
        diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
        diff_opts.single_follow = opt->paths[0];
        diff_opts.break_opt = opt->break_opt;
@@ -412,7 +412,7 @@ int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const cha
        init_tree_desc(&t1, tree1, size1);
        init_tree_desc(&t2, tree2, size2);
        retval = diff_tree(&t1, &t2, base, opt);
-       if (DIFF_OPT_TST(opt, FOLLOW_RENAMES) && diff_might_be_rename()) {
+       if (!*base && DIFF_OPT_TST(opt, FOLLOW_RENAMES) && diff_might_be_rename()) {
                init_tree_desc(&t1, tree1, size1);
                init_tree_desc(&t2, tree2, size2);
                try_to_follow_renames(&t1, &t2, base, opt);