From 6b7c5b7df3f17c79f398dfa9d3b0a3e662570cb5 Mon Sep 17 00:00:00 2001
From: William Boman <william+github@redwill.se>
Date: Thu, 18 Oct 2018 13:12:14 +0200
Subject: [PATCH] fix: add null check in dispose method (#675)

---
 src/services/AppStore.ts | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/services/AppStore.ts b/src/services/AppStore.ts
index 58d0b15f..90aeeaea 100644
--- a/src/services/AppStore.ts
+++ b/src/services/AppStore.ts
@@ -1,4 +1,4 @@
-import { observe } from 'mobx';
+import { observe, Lambda } from 'mobx';
 
 import { OpenAPISpec } from '../types';
 import { loadAndBundleSpec } from '../utils/loadAndBundleSpec';
@@ -58,7 +58,7 @@ export class AppStore {
   marker = new MarkerService();
 
   private scroll: ScrollService;
-  private disposer;
+  private disposer: Lambda | null = null;
 
   constructor(
     spec: OpenAPISpec,
@@ -96,7 +96,9 @@ export class AppStore {
   dispose() {
     this.scroll.dispose();
     this.menu.dispose();
-    this.disposer();
+    if (this.disposer != null) {
+      this.disposer();
+    }
   }
 
   /**