[bugfix] Toast: fix instance when SSR (#1927)

packages/toast/index.js

@@ -20,6 +20,11 @@ let singleton = true;
 let currentOptions = { ...defaultOptions };
 
 function createInstance() {
+  /* istanbul ignore if */
+  if (isServer) {
+    return {};
+  }
+
   if (!queue.length || !singleton) {
     const toast = new (Vue.extend(VueToast))({
       el: document.createElement('div')
@@ -37,11 +42,6 @@ function transformer(options) {
 }
 
 function Toast(options = {}) {
-  /* istanbul ignore if */
-  if (isServer) {
-    return;
-  }
-
   const toast = createInstance();
 
   options = {