util.roles: Return nil if the role has no explicit policy (fixes inheritance)

Previously, if the first inherited role had no opinion, it returned false and
prevented further consultation of other inherited roles.

This bug was found thanks to the implementation of missing test cases
identified through mutation testing.

1 files changed, 1 insertions, 1 deletions

diff --git a/util/roles.lua b/util/roles.lua
index 831ce6ae..a38faa58 100644
--- a/util/roles.lua
+++ b/util/roles.lua
@@ -30,7 +30,7 @@ local function _new_may(permissions, inherited_mays)
 				end
 			end
 		end
-		return false;
+		return nil;
 	end
 end