diff --git a/contrib/diff-highlight/DiffHighlight.pm b/contrib/diff-highlight/DiffHighlight.pm
index e258992..376f577 100644
--- a/contrib/diff-highlight/DiffHighlight.pm
+++ b/contrib/diff-highlight/DiffHighlight.pm
@@ -112,7 +112,7 @@
 	# Since we can receive arbitrary input, there's no optimal
 	# place to flush. Flushing on a blank line is a heuristic that
 	# happens to match git-log output.
-	if (!length) {
+	if (/^$/) {
 		$flush_cb->();
 	}
 }