1 files changed, 7 insertions, 0 deletions
diff --git a/src/metadata.h b/src/metadata.h
index 7336766d..7ba17fa4 100644
--- a/src/metadata.h
+++ b/src/metadata.h
@@ -26,6 +26,8 @@
 
 #include <string>
 
+class bias_to_string_test;
+
 namespace libdcp
 {
 
@@ -49,6 +51,11 @@ public:
 	std::string issuer;
 	std::string creator;
 	std::string issue_date;
+
+private:
+	friend class ::bias_to_string_test;
+	
+	static std::string bias_to_string (int);
 };
 
 }