From 45dec8ac178d62cc1080ef0e222b2c5ce14122a0 Mon Sep 17 00:00:00 2001
From: Sam Vitello <sam.j.vitello@gmail.com>
Date: Mon, 11 Jun 2018 14:32:37 -0600
Subject: [PATCH] fix(EventListener): only stop watching if listener exists

---
 src/utils/EventListener.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/utils/EventListener.js b/src/utils/EventListener.js
index 875208f..fd72177 100644
--- a/src/utils/EventListener.js
+++ b/src/utils/EventListener.js
@@ -180,11 +180,13 @@ class EventListener {
    * @param {string} contractImplementationInstance - Address of the contract to stop watching
    */
   stopWatchingForEvents = contractImplementationInstance => {
-    if (contractImplementationInstance)
-      this.watcherInstances[
+    if (contractImplementationInstance) {
+      const watcherInstance = this.watcherInstances[
         contractImplementationInstance.getContractAddress()
-      ].stopWatching()
-    else
+      ]
+
+      if (watcherInstance) watcherInstance.stopWatching()
+    } else
       this.contractInstances.forEach(instance => {
         this.watcherInstances[instance.getContractAddress()].stopWatching()
       })