修正where方法为空的处理

Author: liu21st

src/db/concern/WhereQuery.php

@@ -37,6 +37,8 @@ public function where($field, $op = null, $condition = null)
         } elseif (true === $field || 1 === $field) {
             $this->options['where']['AND'][] = true;
 
+            return $this;
+        } elseif (empty($field)) {
             return $this;
         }
 
@@ -96,7 +98,7 @@ public function whereOr($field, $op = null, $condition = null)
         $param = func_get_args();
         array_shift($param);
 
-        if (is_array($field)) {
+        if (is_array($field) && !empty($field)) {
             return $this->where(function ($query) use ($param, $condition, $op, $field) {
                 return $query->parseWhereExp('OR', $field, $op, $condition, $param);
             });
@@ -119,7 +121,7 @@ public function whereXor($field, $op = null, $condition = null)
         $param = func_get_args();
         array_shift($param);
 
-        if (is_array($field)) {
+        if (is_array($field) && !empty($field)) {
             return $this->where(function ($query) use ($param, $condition, $op, $field) {
                 return $query->parseWhereExp('XOR', $field, $op, $condition, $param);
             });