refactor(pattern): prototype to class syntax

lib/pattern.js

@@ -4,23 +4,25 @@ const escapeRegExp = require('./escape_regexp');
 
 const rParam = /([:*])([\w?]*)?/g;
 
-function Pattern(rule) {
-  if (rule instanceof Pattern) {
-    return rule;
-  } else if (typeof rule === 'function') {
-    this.match = rule;
-  } else if (rule instanceof RegExp) {
-    this.match = regexFilter(rule);
-  } else if (typeof rule === 'string') {
-    this.match = stringFilter(rule);
-  } else {
-    throw new TypeError('rule must be a function, a string or a regular expression.');
+class Pattern {
+  constructor(rule) {
+    if (rule instanceof Pattern) {
+      return rule;
+    } else if (typeof rule === 'function') {
+      this.match = rule;
+    } else if (rule instanceof RegExp) {
+      this.match = regexFilter(rule);
+    } else if (typeof rule === 'string') {
+      this.match = stringFilter(rule);
+    } else {
+      throw new TypeError('rule must be a function, a string or a regular expression.');
+    }
   }
-}
 
-Pattern.prototype.test = function(str) {
-  return Boolean(this.match(str));
-};
+  test(str) {
+    return Boolean(this.match(str));
+  }
+}
 
 function regexFilter(rule) {
   return str => str.match(rule);