Database Loader Stub and lazy loading in Db_Info

app/code/community/EcomDev/PHPUnit/Model/Fixture/Loader/Database.php

+<?php
+
+class EcomDev_PHPUnit_Model_Fixture_Loader_Database implements
+    EcomDev_PHPUnit_Model_Fixture_LoaderInterface
+{
+    /**
+     * Flushes the data that was added before loading
+     *
+     * @return mixed
+     */
+    public function flush()
+    {
+        // TODO: Implement flush() method.
+    }
+
+
+    /**
+     * This one should realize possibility to merge data with existing Magento data
+     *
+     * @param $data
+     *
+     * @return mixed
+     */
+    public function merge($data)
+    {
+        // TODO: Implement merge() method.
+    }
+
+
+    /**
+     * Overrides the data in the system for specified data
+     *
+     * It should realize default functionality
+     * for a default fixture processors
+     *
+     * @param array $data
+     *
+     * @return $this
+     * @throws InvalidArgumentException
+     */
+    public function override($data)
+    {
+        // TODO: Implement override() method.
+    }
+
+
+    /**
+     * Restores original data, that was modified by fixture flushing
+     *
+     * @return mixed
+     */
+    public function restore()
+    {
+        // TODO: Implement restore() method.
+    }
+}

app/code/community/EcomDev/PHPUnit/Model/Mysql4/Db/Info.php

@@ -16,8 +16,9 @@ class EcomDev_PHPUnit_Model_Mysql4_Db_Info implements EcomDev_PHPUnit_Model_Mysq
      */
     public function fetch()
     {
-        // reset information
-        $this->reset();
+        if ($this->_information !== null) {
+            return $this;
+        }
 
         // iterate over each available table
         $listTables = $this->getAdapter()->listTables();
@@ -42,6 +43,8 @@ class EcomDev_PHPUnit_Model_Mysql4_Db_Info implements EcomDev_PHPUnit_Model_Mysq
 
             $this->_information[$tableName] = $data;
         }
+
+        return $this;
     }
 
 
@@ -65,6 +68,8 @@ class EcomDev_PHPUnit_Model_Mysql4_Db_Info implements EcomDev_PHPUnit_Model_Mysq
      */
     public function getTableDependencies($tableName)
     {
+        $this->fetch();
+
         if (isset($this->_information[$tableName])
             && $this->_information[$tableName] instanceof Varien_Object
         )
@@ -83,7 +88,7 @@ class EcomDev_PHPUnit_Model_Mysql4_Db_Info implements EcomDev_PHPUnit_Model_Mysq
      */
     public function reset()
     {
-        $this->_information = array();
+        $this->_information = null;
     }