diff --git a/src/store.js b/src/store.js
index fce8d60ae..a5b694f55 100644
--- a/src/store.js
+++ b/src/store.js
@@ -22,7 +22,7 @@ export class Store {
       state = {}
     } = options
     if (typeof state === 'function') {
-      state = state()
+      state = state() || {}
     }
 
     // store internal state