Prevent error on getAttributes when classes collection doesn't exist

src/css_composer/index.js

@@ -201,7 +201,7 @@ module.exports = () => {
       var rule = this.get(selectors, s, w, opt);
 
       // do not create rules that were found before
-      // unless this is an at-rule, for which multiple declarations
+      // unless this is a single at-rule, for which multiple declarations
       // make sense (e.g. multiple `@font-type`s)
       if (rule && rule.config && !rule.config.singleAtRule) {
         return rule;

src/dom_components/model/Component.js

@@ -153,13 +153,13 @@ const Component = Backbone.Model.extend(Styleable).extend(
       this.config = opt.config || {};
       this.ccid = Component.createId(this);
       this.set('attributes', this.get('attributes') || {});
-      this.listenTo(this, 'change:script', this.scriptUpdated);
-      this.listenTo(this, 'change:tagName', this.tagUpdated);
-      this.listenTo(this, 'change:attributes', this.attrUpdated);
       this.initClasses();
       this.initTraits();
       this.initComponents();
       this.initToolbar();
+      this.listenTo(this, 'change:script', this.scriptUpdated);
+      this.listenTo(this, 'change:tagName', this.tagUpdated);
+      this.listenTo(this, 'change:attributes', this.attrUpdated);
       this.set('status', '');
 
       // Register global updates for collection properties
@@ -356,7 +356,9 @@ const Component = Backbone.Model.extend(Styleable).extend(
       const id = this.getId();
 
       // Add classes
-      this.get('classes').each(cls => classes.push(cls.get('name')));
+      this.get('classes').forEach(cls =>
+        classes.push(isString(cls) ? cls : cls.get('name'))
+      );
       classes.length && (attributes.class = classes.join(' '));
 
       // Check if we need an ID on the component