--- /dev/null
+/* @flow */
+"use strict";
+
+/**
+ * Given an object of violation messages, return another
+ * that provides the same messages postfixed with the rule
+ * that has been violated.
+ *
+ * @param {string} ruleName
+ * @param {object} messages - Object whose keys are message identifiers
+ * and values are either message strings or functions that return message strings
+ * @return {object} New message object, whose messages will be marked with the rule name
+ */
+module.exports = function(
+ ruleName /*: string*/,
+ messages /*: Object*/
+) /*: Object*/ {
+ return Object.keys(messages).reduce((newMessages, messageId) => {
+ const messageText = messages[messageId];
+ if (typeof messageText === "string") {
+ newMessages[messageId] = `${messageText} (${ruleName})`;
+ } else {
+ newMessages[messageId] = function() {
+ return `${messageText.apply(null, arguments)} (${ruleName})`;
+ };
+ }
+ return newMessages;
+ }, {});
+};