Add tests for corner cases

test/spec/ol/events/eventtarget.test.js

@@ -130,6 +130,23 @@ describe('ol.events.EventTarget', function() {
       expect(called).to.eql([3]);
       expect(eventTarget.getListeners('foo')).to.have.length(1);
     });
+    it('is safe to do weird things in listeners', function() {
+      eventTarget.addEventListener('foo', spy2);
+      eventTarget.addEventListener('foo', function weird(evt) {
+        eventTarget.removeEventListener('foo', weird);
+        eventTarget.removeEventListener('foo', spy1);
+        eventTarget.dispatchEvent('foo');
+        eventTarget.removeEventListener('foo', spy2);
+        eventTarget.dispatchEvent('foo');
+        evt.preventDefault();
+      });
+      eventTarget.addEventListener('foo', spy1);
+      expect(function() {
+        eventTarget.dispatchEvent('foo');
+      }).not.to.throwException();
+      expect(called).to.eql([2, 2]);
+      expect(eventTarget.getListeners('foo')).to.be(undefined);
+    });
   });
 
   describe('#dispose()', function() {