/**
* Process an arithmetic expression node for nullability
*
* @param FunctionCallExpression $expression The function call expression
* node to process.
* @param AbstractExpression $parentExpression The parent expression of
* expression node to process.
*
* @return LogicalExpression or NULL
*/
private function _processFuncationCallNode(FunctionCallExpression $expression, $parentExpression)
{
$paramExpressions = $expression->getParamExpressions();
$checkNullForMostChild = strcmp($expression->getFunctionDescription()->functionName, 'is_null') === 0;
$resultExpression = null;
foreach ($paramExpressions as $paramExpression) {
$resultExpression1 = $this->_processNodeForNullability($paramExpression, $expression, !$checkNullForMostChild);
if ($resultExpression1 != null && $resultExpression != null) {
$resultExpression = $this->_mergeNullableExpressionTrees($resultExpression, $resultExpression1);
} else {
if ($resultExpression1 != null && $resultExpression == null) {
$resultExpression = $resultExpression1;
}
}
}
if ($resultExpression == null) {
return null;
}
if ($parentExpression == null) {
return new LogicalExpression($resultExpression, $expression, ExpressionType::AND_LOGICAL);
}
return $resultExpression;
}
