// Remove cleanPositions() in modules when a hook module is added (since the hook module go in last position, we don't need to recalculate all positions) -> greatly improve module installation phase in new installer

classes/Module.php

@@ -632,19 +632,14 @@ abstract class ModuleCore
 				$position = 0;
 
 			// Register module in hook
-			$result = Db::getInstance()->autoExecute(_DB_PREFIX_.'hook_module', array(
+			$return &= Db::getInstance()->autoExecute(_DB_PREFIX_.'hook_module', array(
 				'id_module' => (int)$this->id,
 				'id_hook' => (int)$hookID,
 				'id_shop' => (int)$shopID,
 				'position' => (int)($position + 1),
 			), 'INSERT');
-			if (!$result)
-				$return &= false;
 		}
 
-		// Clean modules position
-		$this->cleanPositions($hookID, $shopList);
-
 		return $return;
 	}