diff --git a/test/unit/mocha.spec.js b/test/unit/mocha.spec.js
index 5cb6319d4d..aa884f0cbd 100644
--- a/test/unit/mocha.spec.js
+++ b/test/unit/mocha.spec.js
@@ -78,6 +78,19 @@ describe('Mocha', function() {
     });
   });
 
+  describe('.runnerOn()', function() {
+    it('should add the given event to the runnerEvents array', function() {
+      var mocha = new Mocha(opts);
+      var fn = function() {};
+      mocha.runnerOn('fake', fn);
+      expect(mocha.runnerEvents, 'to have length', 1);
+      expect(mocha.runnerEvents[0][0], 'to be', 'fake');
+      expect(mocha.runnerEvents[0][1], 'to be', fn);
+      var runner = mocha.run();
+      expect(runner.listenerCount('fake'), 'to be', 1);
+    });
+  });
+
   describe('.invert()', function() {
     it('should set the invert option to true', function() {
       var mocha = new Mocha(opts);