<?php
/*
* This file is part of Twig.
*
* (c) Fabien Potencier
* (c) Armin Ronacher
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Twig;
use Twig\Error\SyntaxError;
/**
* Represents a token stream.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
final class TokenStream
{
private $tokens;
private $current = 0;
private $source;
public function __construct(array $tokens, Source $source = null)
{
$this->tokens = $tokens;
$this->source = $source ?: new Source('', '');
}
public function __toString()
{
return implode("\n", $this->tokens);
}
public function injectTokens(array $tokens)
{
$this->tokens = array_merge(\array_slice($this->tokens, 0, $this->current), $tokens, \array_slice($this->tokens, $this->current));
}
/**
* Sets the pointer to the next token and returns the old one.
*/
public function next(): Token
{
if (!isset($this->tokens[++$this->current])) {
throw new SyntaxError('Unexpected end of template.', $this->tokens[$this->current - 1]->getLine(), $this->source);
}
return $this->tokens[$this->current - 1];
}
/**
* Tests a token, sets the pointer to the next one and returns it or throws a syntax error.
*
* @return Token|null The next token if the condition is true, null otherwise
*/
public function nextIf($primary, $secondary = null)
{
if ($this->tokens[$this->current]->test($primary, $secondary)) {
return $this->next();
}
}
/**
* Tests a token and returns it or throws a syntax error.
*/
public function expect($type, $value = null, string $message = null): Token
{
$token = $this->tokens[$this->current];
if (!$token->test($type, $value)) {
$line = $token->getLine();
throw new SyntaxError(sprintf('%sUnexpected token "%s"%s ("%s" expected%s).',
$message ? $message.'. ' : '',
Token::typeToEnglish($token->getType()),
$token->getValue() ? sprintf(' of value "%s"', $token->getValue()) : '',
Token::typeToEnglish($type), $value ? sprintf(' with value "%s"', $value) : ''),
$line,
$this->source
);
}
$this->next();
return $token;
}
/**
* Looks at the next token.
*/
public function look(int $number = 1): Token
{
if (!isset($this->tokens[$this->current + $number])) {
throw new SyntaxError('Unexpected end of template.', $this->tokens[$this->current + $number - 1]->getLine(), $this->source);
}
return $this->tokens[$this->current + $number];
}
/**
* Tests the current token.
*/
public function test($primary, $secondary = null): bool
{
return $this->tokens[$this->current]->test($primary, $secondary);
}
/**
* Checks if end of stream was reached.
*/
public function isEOF(): bool
{
return /* Token::EOF_TYPE */ -1 === $this->tokens[$this->current]->getType();
}
public function getCurrent(): Token
{
return $this->tokens[$this->current];
}
/**
* Gets the source associated with this stream.
*
* @internal
*/
public function getSourceContext(): Source
{
return $this->source;
}
}
class_alias('Twig\TokenStream', 'Twig_TokenStream');