test-lib: unset GIT_TRACE

diff --git a/builtin-diff-tree.c b/builtin-diff-tree.c
index 3409a39a9f73f9ed67547f5cc79619c1e402f47b..ae1cde9d005cb64ca2b1a5de45750abff04d444d 100644 (file)
--- a/builtin-diff-tree.c
+++ b/builtin-diff-tree.c
@@ -84,6 +84,9 @@ int cmd_diff_tree(int argc, const char **argv, char **envp)
                usage(diff_tree_usage);
        }
 
+       if (!opt->diffopt.output_format)
+               opt->diffopt.output_format = DIFF_FORMAT_RAW;
+
        /*
         * NOTE! We expect "a ^b" to be equal to "a..b", so we
         * reverse the order of the objects if the second one