first upload all files

Themes/Storefront/resources/assets/public/js/Errors.js

@@ -0,0 +1,48 @@
+import Vue from 'vue';
+
+export default class {
+    constructor() {
+        this.errors = {};
+    }
+
+    record(errors) {
+        this.errors = errors;
+    }
+
+    any() {
+        return Object.keys(this.errors).length > 0;
+    }
+
+    has(key) {
+        return this.errors.hasOwnProperty(key);
+    }
+
+    get(key) {
+        if (this.errors[key]) {
+            return this.errors[key][0];
+        }
+    }
+
+    clear(key) {
+        if (key === undefined) {
+            return;
+        }
+
+        Vue.delete(this.errors, this.normalizeKey(key));
+    }
+
+    reset() {
+        this.errors = {};
+    }
+
+    normalizeKey(key) {
+        let keyParts = key.replace('[]', '').split('[');
+
+        // No need to normalize the key.
+        if (keyParts.length === 1) {
+            return key;
+        }
+
+        return keyParts.join('.').slice(0, -1);
+    }
+}