/**
* Generates Comparison Expression
*
* @param AbstractExpression $left The LHS expression.
* @param AbstractExpression $right The RHS expression.
* @param ExpressionToken $expressionToken The comparison expression token.
* @param boolean $isPHPExpressionProvider
*
* @return AbstractExpression
*/
private static function _generateComparisonExpression($left, $right, $expressionToken, $isPHPExpressionProvider)
{
FunctionDescription::verifyRelationalOpArguments($expressionToken, $left, $right);
//We need special handling for comparison of following types:
//1. String
//2. DateTime
//3. Guid
//4. Binary
//Will make these comparison as function calls, which will
// be converted to language specific function call by expression
// provider
$string = new String();
if ($left->typeIs($string) && $right->typeIs($string)) {
$strcmpFunctions = FunctionDescription::stringComparisonFunctions();
$left = new FunctionCallExpression($strcmpFunctions[0], array($left, $right));
$right = new ConstantExpression(0, new Int32());
}
$dateTime = new DateTime();
if ($left->typeIs($dateTime) && $right->typeIs($dateTime)) {
$dateTimeCmpFunctions = FunctionDescription::dateTimeComparisonFunctions();
$left = new FunctionCallExpression($dateTimeCmpFunctions[0], array($left, $right));
$right = new ConstantExpression(0, new Int32());
}
$guid = new Guid();
if ($left->typeIs($guid) && $right->typeIs($guid)) {
$guidEqualityFunctions = FunctionDescription::guidEqualityFunctions();
$left = new FunctionCallExpression($guidEqualityFunctions[0], array($left, $right));
$right = new ConstantExpression(true, new Boolean());
}
$binary = new Binary();
if ($left->typeIs($binary) && $right->typeIs($binary)) {
$binaryEqualityFunctions = FunctionDescription::binaryEqualityFunctions();
$left = new FunctionCallExpression($binaryEqualityFunctions[0], array($left, $right));
$right = new ConstantExpression(true, new Boolean());
}
$null = new Null1();
if ($left->typeIs($null) || $right->typeIs($null)) {
// If the end user is responsible for implementing IExpressionProvider
// then the sub-tree for a nullability check would be:
//
// RelationalExpression(EQ/NE)
// |
// ------------
// | |
// | |
// CustomerID NULL
//
// Otherwise (In case of default PHPExpressionProvider):
//
// CustomerID eq null
// ==================
//
// FunctionCallExpression(is_null)
// |
// |- Signature => bool (typeof(CustomerID))
// |- args => {CustomerID}
//
//
// CustomerID ne null
// ==================
//
// UnaryExpression (not)
// |
// FunctionCallExpression(is_null)
// |
// |- Signature => bool (typeof(CustomerID))
// |- args => {CustomerID}
//
if ($isPHPExpressionProvider) {
$arg = $left->typeIs($null) ? $right : $left;
$isNullFunctionDescription = new FunctionDescription('is_null', new Boolean(), array($arg->getType()));
switch ($expressionToken->Text) {
case ODataConstants::KEYWORD_EQUAL:
return new FunctionCallExpression($isNullFunctionDescription, array($arg));
break;
case ODataConstants::KEYWORD_NOT_EQUAL:
return new UnaryExpression(new FunctionCallExpression($isNullFunctionDescription, array($arg)), ExpressionType::NOT_LOGICAL, new Boolean());
break;
}
}
}
switch ($expressionToken->Text) {
case ODataConstants::KEYWORD_EQUAL:
return new RelationalExpression($left, $right, ExpressionType::EQUAL);
case ODataConstants::KEYWORD_NOT_EQUAL:
return new RelationalExpression($left, $right, ExpressionType::NOTEQUAL);
case ODataConstants::KEYWORD_GREATERTHAN:
return new RelationalExpression($left, $right, ExpressionType::GREATERTHAN);
case ODataConstants::KEYWORD_GREATERTHAN_OR_EQUAL:
return new RelationalExpression($left, $right, ExpressionType::GREATERTHAN_OR_EQUAL);
case ODataConstants::KEYWORD_LESSTHAN:
return new RelationalExpression($left, $right, ExpressionType::LESSTHAN);
default:
return new RelationalExpression($left, $right, ExpressionType::LESSTHAN_OR_EQUAL);
}
}
/**
* 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|null
*/
private function _processFunctionCallNode(FunctionCallExpression $expression, $parentExpression)
{
$paramExpressions = $expression->getParamExpressions();
$checkNullForMostChild = strcmp($expression->getFunctionDescription()->name, '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;
}
