/**
* Parse primary expression.
*
* @return Node The primary node.
* @throws SyntaxErrorException if no operand or unary operator can be found.
*/
private function parsePrimary()
{
/* @var Token $token */
$token = $this->stream->current();
if ($token && $this->operatorTable->isUnary($token)) {
$this->stream->next();
$operator = $this->operatorTable->getUnaryOperator($token);
$operatorNode = $operator->getNode();
$node = $operatorNode($this->parseExpression($operator->getPrecedence()));
} else {
if ($token) {
$node = $this->parseOperand();
$this->stream->next();
} else {
throw new SyntaxErrorException('Operand or unary operator expected; but end of stream reached');
}
}
return $node;
}
/**
* Test if the `isUnary` method returns false if the given token isn't an unary operator.
*/
public function testIsUnaryReturnsFalse()
{
$operator = new BinaryOperator(1, 10, BinaryOperator::LEFT, function () {
});
$token = new Token($operator->getCode(), '+', 1);
$table = new OperatorTable();
$table->addOperator($operator);
$this->assertFalse($table->isUnary($token));
}
