Fix prependListener in wildcard mode

EventEmitter2 · Feb 14, 2021 · aab7c88 · aab7c88
1 parent 90a37aa
commit aab7c88
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Showing 2 changed files with 36 additions and 4 deletions.
diff --git a/lib/eventemitter2.js b/lib/eventemitter2.js
@@ -599,7 +599,7 @@
     return listeners;
   }
 
-  function growListenerTree(type, listener) {
+  function growListenerTree(type, listener, prepend) {
     var len = 0, j = 0, i, delimiter = this.delimiter, dl= delimiter.length, ns;
 
     if(typeof type==='string') {
@@ -648,7 +648,11 @@
             tree._listeners = [tree._listeners];
           }
 
-          tree._listeners.push(listener);
+          if (prepend) {
+            tree._listeners.unshift(listener);
+          } else {
+            tree._listeners.push(listener);
+          }
 
           if (
               !tree._listeners.warned &&
@@ -1229,7 +1233,7 @@
     }
 
     if (this.wildcard) {
-      growListenerTree.call(this, type, listener);
+      growListenerTree.call(this, type, listener, prepend);
       return returnValue;
     }
 

diff --git a/test/wildcardEvents/addListener.js b/test/wildcardEvents/addListener.js
@@ -333,6 +333,34 @@ module.exports = simpleEvents({
 
     test.expect(5);
     test.done();
-  }
+  },
+
+
+  '13. Use prepend on wildcards mode.': function (test) {
+
+    var emitter = new EventEmitter2({
+      wildcard: true
+    });
+
+    var type = ['some', 'listener', 'bar'];
+
+    const function1 = function () {
+      test.ok(true, 'The event was raised');
+    }
+
+    const function2 = function () {
+      test.ok(true, 'The event was raised');
+    }
+
+    emitter.on(type, function2);
+
+    emitter.prependListener(type, function1);
+
+    test.equal(emitter.listeners(type)[0], function1, 'Prepended listener is first');
+
+    test.expect(1);
+    test.done();
+
+  },
 
 });