健壮性处理。

@@ -500,7 +500,7 @@ function _getSortNavAsync(smallSortId, gender) {
         let data = yield searchAPI.getSortByConditionAsync({sort: smallSortId});
 
         if (data.data) {
-            let sort = _.head(data.data.sort);
+            let sort = _.head(data.data.sort) || {};
 
             // 一级分类
             navs.push({
@@ -511,7 +511,7 @@ function _getSortNavAsync(smallSortId, gender) {
 
             if (sort.sub) {
                 // 二级分类
-                let subSort = _.head(sort.sub);
+                let subSort = _.head(sort.sub) || {};
 
                 navs.push({
                     href: helpers.urlFormat('', {msort: sort.sort_id, misort: subSort.sort_id, gender: gender}, 'list'),
@@ -1212,6 +1212,10 @@ const _getSizeAttrByMaxSortId = (maxSortId, sizeList) => {
 
     let attributeNames = {};
 
+    if(_.isEmpty(sizeList)){
+        return sizeInfos;
+    }
+
     // 获取属性名称
     sizeList.sizeAttributeBos.forEach(size => {
         attributeNames[size.id] = size.attributeName;
@@ -1309,12 +1313,15 @@ const _getSeoByGoodsInfo = function(goodsInfo, navs) {
     let sortName = '';
     let description = '';
 
+    goodsInfo = goodsInfo || {};
+    navs = navs || [];
+
     if (!_.isEmpty(goodsInfo.brandName)) {
         title = goodsInfo.brandName + ' ';
         brandName = goodsInfo.brandName;
     }
 
-    if (!_.isEmpty(navs) && navs[1].name) {
+    if (!_.isEmpty(navs) && navs[1] && navs[1].name) {
         sortName = navs[1].name;
         title += navs[1].name + '|';
     }