fix missing callback

src/plugins/hooks.js

@@ -14,17 +14,17 @@ module.exports = function(Plugins) {
 			`data.priority`, the relative priority of the method when it is eventually called (default: 10)
 	*/
 	Plugins.registerHook = function(id, data, callback) {
+		callback = callback || function() {};
 		function register() {
 			Plugins.loadedHooks[data.hook] = Plugins.loadedHooks[data.hook] || [];
 			Plugins.loadedHooks[data.hook].push(data);
 
-			if (typeof callback === 'function') {
-				callback();
-			}
+			callback();
 		}
 
 		if (!data.hook) {
-			return winston.warn('[plugins/' + id + '] registerHook called with invalid data.hook', data);
+			winston.warn('[plugins/' + id + '] registerHook called with invalid data.hook', data);
+			return callback();
 		}
 
 		var method;
@@ -69,6 +69,7 @@ module.exports = function(Plugins) {
 				register();
 			} else {
 				winston.warn('[plugins/' + id + '] Hook method mismatch: ' + data.hook + ' => ' + data.method);
+				return callback();
 			}
 		}
 	};