<?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;
use Twig\Node\BlockNode;
use Twig\Node\BlockReferenceNode;
use Twig\Node\BodyNode;
use Twig\Node\Expression\AbstractExpression;
use Twig\Node\MacroNode;
use Twig\Node\ModuleNode;
use Twig\Node\Node;
use Twig\Node\NodeCaptureInterface;
use Twig\Node\NodeOutputInterface;
use Twig\Node\PrintNode;
use Twig\Node\TextNode;
use Twig\TokenParser\TokenParserInterface;
/**
* @author Fabien Potencier <fabien@symfony.com>
*/
class Parser
{
private $stack = [];
private $stream;
private $parent;
private $visitors;
private $expressionParser;
private $blocks;
private $blockStack;
private $macros;
private $env;
private $importedSymbols;
private $traits;
private $embeddedTemplates = [];
private $varNameSalt = 0;
public function __construct(Environment $env)
{
$this->env = $env;
}
public function getVarName(): string
{
return sprintf('__internal_parse_%d', $this->varNameSalt++);
}
public function parse(TokenStream $stream, $test = null, bool $dropNeedle = false): ModuleNode
{
$vars = get_object_vars($this);
unset($vars['stack'], $vars['env'], $vars['handlers'], $vars['visitors'], $vars['expressionParser'], $vars['reservedMacroNames']);
$this->stack[] = $vars;
// node visitors
if (null === $this->visitors) {
$this->visitors = $this->env->getNodeVisitors();
}
if (null === $this->expressionParser) {
$this->expressionParser = new ExpressionParser($this, $this->env);
}
$this->stream = $stream;
$this->parent = null;
$this->blocks = [];
$this->macros = [];
$this->traits = [];
$this->blockStack = [];
$this->importedSymbols = [[]];
$this->embeddedTemplates = [];
$this->varNameSalt = 0;
try {
$body = $this->subparse($test, $dropNeedle);
if (null !== $this->parent && null === $body = $this->filterBodyNodes($body)) {
$body = new Node();
}
} catch (SyntaxError $e) {
if (!$e->getSourceContext()) {
$e->setSourceContext($this->stream->getSourceContext());
}
if (!$e->getTemplateLine()) {
$e->setTemplateLine($this->stream->getCurrent()->getLine());
}
throw $e;
}
$node = new ModuleNode(new BodyNode([$body]), $this->parent, new Node($this->blocks), new Node($this->macros), new Node($this->traits), $this->embeddedTemplates, $stream->getSourceContext());
$traverser = new NodeTraverser($this->env, $this->visitors);
$node = $traverser->traverse($node);
// restore previous stack so previous parse() call can resume working
foreach (array_pop($this->stack) as $key => $val) {
$this->$key = $val;
}
return $node;
}
public function subparse($test, bool $dropNeedle = false): Node
{
$lineno = $this->getCurrentToken()->getLine();
$rv = [];
while (!$this->stream->isEOF()) {
switch ($this->getCurrentToken()->getType()) {
case /* Token::TEXT_TYPE */ 0:
$token = $this->stream->next();
$rv[] = new TextNode($token->getValue(), $token->getLine());
break;
case /* Token::VAR_START_TYPE */ 2:
$token = $this->stream->next();
$expr = $this->expressionParser->parseExpression();
$this->stream->expect(/* Token::VAR_END_TYPE */ 4);
$rv[] = new PrintNode($expr, $token->getLine());
break;
case /* Token::BLOCK_START_TYPE */ 1:
$this->stream->next();
$token = $this->getCurrentToken();
if (/* Token::NAME_TYPE */ 5 !== $token->getType()) {
throw new SyntaxError('A block must start with a tag name.', $token->getLine(), $this->stream->getSourceContext());
}
if (null !== $test && $test($token)) {
if ($dropNeedle) {
$this->stream->next();
}
if (1 === \count($rv)) {
return $rv[0];
}
return new Node($rv, [], $lineno);
}
if (!$subparser = $this->env->getTokenParser($token->getValue())) {
if (null !== $test) {
$e = new SyntaxError(sprintf('Unexpected "%s" tag', $token->getValue()), $token->getLine(), $this->stream->getSourceContext());
if (\is_array($test) && isset($test[0]) && $test[0] instanceof TokenParserInterface) {
$e->appendMessage(sprintf(' (expecting closing tag for the "%s" tag defined near line %s).', $test[0]->getTag(), $lineno));
}
} else {
$e = new SyntaxError(sprintf('Unknown "%s" tag.', $token->getValue()), $token->getLine(), $this->stream->getSourceContext());
$e->addSuggestions($token->getValue(), array_keys($this->env->getTokenParsers()));
}
throw $e;
}
$this->stream->next();
$subparser->setParser($this);
$node = $subparser->parse($token);
if (null !== $node) {
$rv[] = $node;
}
break;
default:
throw new SyntaxError('Lexer or parser ended up in unsupported state.', $this->getCurrentToken()->getLine(), $this->stream->getSourceContext());
}
}
if (1 === \count($rv)) {
return $rv[0];
}
return new Node($rv, [], $lineno);
}
public function getBlockStack(): array
{
return $this->blockStack;
}
public function peekBlockStack()
{
return $this->blockStack[\count($this->blockStack) - 1] ?? null;
}
public function popBlockStack(): void
{
array_pop($this->blockStack);
}
public function pushBlockStack($name): void
{
$this->blockStack[] = $name;
}
public function hasBlock(string $name): bool
{
return isset($this->blocks[$name]);
}
public function getBlock(string $name): Node
{
return $this->blocks[$name];
}
public function setBlock(string $name, BlockNode $value): void
{
$this->blocks[$name] = new BodyNode([$value], [], $value->getTemplateLine());
}
public function hasMacro(string $name): bool
{
return isset($this->macros[$name]);
}
public function setMacro(string $name, MacroNode $node): void
{
$this->macros[$name] = $node;
}
public function addTrait($trait): void
{
$this->traits[] = $trait;
}
public function hasTraits(): bool
{
return \count($this->traits) > 0;
}
public function embedTemplate(ModuleNode $template)
{
$template->setIndex(mt_rand());
$this->embeddedTemplates[] = $template;
}
public function addImportedSymbol(string $type, string $alias, string $name = null, AbstractExpression $node = null): void
{
$this->importedSymbols[0][$type][$alias] = ['name' => $name, 'node' => $node];
}
public function getImportedSymbol(string $type, string $alias)
{
// if the symbol does not exist in the current scope (0), try in the main/global scope (last index)
return $this->importedSymbols[0][$type][$alias] ?? ($this->importedSymbols[\count($this->importedSymbols) - 1][$type][$alias] ?? null);
}
public function isMainScope(): bool
{
return 1 === \count($this->importedSymbols);
}
public function pushLocalScope(): void
{
array_unshift($this->importedSymbols, []);
}
public function popLocalScope(): void
{
array_shift($this->importedSymbols);
}
public function getExpressionParser(): ExpressionParser
{
return $this->expressionParser;
}
public function getParent(): ?Node
{
return $this->parent;
}
public function setParent(?Node $parent): void
{
$this->parent = $parent;
}
public function getStream(): TokenStream
{
return $this->stream;
}
public function getCurrentToken(): Token
{
return $this->stream->getCurrent();
}
private function filterBodyNodes(Node $node, bool $nested = false): ?Node
{
// check that the body does not contain non-empty output nodes
if (
($node instanceof TextNode && !ctype_space($node->getAttribute('data')))
||
(!$node instanceof TextNode && !$node instanceof BlockReferenceNode && $node instanceof NodeOutputInterface)
) {
if (false !== strpos((string) $node, \chr(0xEF).\chr(0xBB).\chr(0xBF))) {
$t = substr($node->getAttribute('data'), 3);
if ('' === $t || ctype_space($t)) {
// bypass empty nodes starting with a BOM
return null;
}
}
throw new SyntaxError('A template that extends another one cannot include content outside Twig blocks. Did you forget to put the content inside a {% block %} tag?', $node->getTemplateLine(), $this->stream->getSourceContext());
}
// bypass nodes that "capture" the output
if ($node instanceof NodeCaptureInterface) {
// a "block" tag in such a node will serve as a block definition AND be displayed in place as well
return $node;
}
// "block" tags that are not captured (see above) are only used for defining
// the content of the block. In such a case, nesting it does not work as
// expected as the definition is not part of the default template code flow.
if ($nested && $node instanceof BlockReferenceNode) {
throw new SyntaxError('A block definition cannot be nested under non-capturing nodes.', $node->getTemplateLine(), $this->stream->getSourceContext());
}
if ($node instanceof NodeOutputInterface) {
return null;
}
// here, $nested means "being at the root level of a child template"
// we need to discard the wrapping "Node" for the "body" node
$nested = $nested || Node::class !== \get_class($node);
foreach ($node as $k => $n) {
if (null !== $n && null === $this->filterBodyNodes($n, $nested)) {
$node->removeNode($k);
}
}
return $node;
}
}