bug: prevent crashes on hydration (#146)

Author: Quicksaver

src/index.js

@@ -31,6 +31,7 @@ class FlickityComponent extends Component {
   }
 
   componentDidUpdate(prevProps, prevState) {
+    if (!this.flkty) return;
     const {
       children,
       options: { draggable, initialIndex },
@@ -39,7 +40,6 @@ class FlickityComponent extends Component {
     } = this.props;
     const { flickityReady } = this.state;
     if (reloadOnUpdate || (!prevState.flickityReady && flickityReady)) {
-      if (!this.flkty) return;
       const isActive = this.flkty.isActive;
       this.flkty.deactivate();
       this.flkty.selectedIndex = initialIndex || 0;
@@ -61,7 +61,7 @@ class FlickityComponent extends Component {
   }
 
   async componentDidMount() {
-    if (!canUseDOM) return null;
+    if (!canUseDOM || !this.carousel) return null;
     const Flickity = (await import('flickity')).default;
     const { flickityRef, options } = this.props;
     this.flkty = new Flickity(this.carousel, options);