check if activeTunnel is available during close callback

Author: delabiejochen

lib/tunnel-launcher.js

@@ -134,9 +134,13 @@ function run (options, callback) {
 
     activeTunnel.close = closeCallback => {
         if (closeCallback) {
-            activeTunnel.on('close', () => {
+            if (!activeTunnel) {
                 closeCallback()
-            })
+            } else {
+                activeTunnel.on('close', () => {
+                    closeCallback()
+                })
+            }
         }
         activeTunnel.kill('SIGINT')
     }