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mirror of https://github.com/danog/PHP-Parser.git synced 2024-11-30 04:19:30 +01:00
PHP-Parser/lib/PhpParser/ParserAbstract.php
Nikita Popov a947e731c3 Add useConsistentVariableNodes mode
The parameter case is a bit weird, because the subnode is called
"name" here, rather than "var". Nothing we can do about that in
this version though.

The two parser options might be merged. I've kept it separate,
because I think this variable representation should become the
default (or even only representation) in the future, while I'm
less sure about the Identifier thing.
2016-12-23 00:10:59 +01:00

743 lines
30 KiB
PHP

<?php
namespace PhpParser;
/*
* This parser is based on a skeleton written by Moriyoshi Koizumi, which in
* turn is based on work by Masato Bito.
*/
use PhpParser\Node\Name;
use PhpParser\Node\Param;
use PhpParser\Node\Scalar\LNumber;
use PhpParser\Node\Scalar\String_;
use PhpParser\Node\Stmt\Class_;
use PhpParser\Node\Stmt\ClassConst;
use PhpParser\Node\Stmt\ClassMethod;
use PhpParser\Node\Stmt\Interface_;
use PhpParser\Node\Stmt\Namespace_;
use PhpParser\Node\Stmt\Property;
use PhpParser\Node\Stmt\TryCatch;
use PhpParser\Node\Stmt\UseUse;
abstract class ParserAbstract implements Parser
{
const SYMBOL_NONE = -1;
/*
* The following members will be filled with generated parsing data:
*/
/** @var int Size of $tokenToSymbol map */
protected $tokenToSymbolMapSize;
/** @var int Size of $action table */
protected $actionTableSize;
/** @var int Size of $goto table */
protected $gotoTableSize;
/** @var int Symbol number signifying an invalid token */
protected $invalidSymbol;
/** @var int Symbol number of error recovery token */
protected $errorSymbol;
/** @var int Action number signifying default action */
protected $defaultAction;
/** @var int Rule number signifying that an unexpected token was encountered */
protected $unexpectedTokenRule;
protected $YY2TBLSTATE;
protected $YYNLSTATES;
/** @var array Map of lexer tokens to internal symbols */
protected $tokenToSymbol;
/** @var array Map of symbols to their names */
protected $symbolToName;
/** @var array Names of the production rules (only necessary for debugging) */
protected $productions;
/** @var array Map of states to a displacement into the $action table. The corresponding action for this
* state/symbol pair is $action[$actionBase[$state] + $symbol]. If $actionBase[$state] is 0, the
action is defaulted, i.e. $actionDefault[$state] should be used instead. */
protected $actionBase;
/** @var array Table of actions. Indexed according to $actionBase comment. */
protected $action;
/** @var array Table indexed analogously to $action. If $actionCheck[$actionBase[$state] + $symbol] != $symbol
* then the action is defaulted, i.e. $actionDefault[$state] should be used instead. */
protected $actionCheck;
/** @var array Map of states to their default action */
protected $actionDefault;
/** @var array Map of non-terminals to a displacement into the $goto table. The corresponding goto state for this
* non-terminal/state pair is $goto[$gotoBase[$nonTerminal] + $state] (unless defaulted) */
protected $gotoBase;
/** @var array Table of states to goto after reduction. Indexed according to $gotoBase comment. */
protected $goto;
/** @var array Table indexed analogously to $goto. If $gotoCheck[$gotoBase[$nonTerminal] + $state] != $nonTerminal
* then the goto state is defaulted, i.e. $gotoDefault[$nonTerminal] should be used. */
protected $gotoCheck;
/** @var array Map of non-terminals to the default state to goto after their reduction */
protected $gotoDefault;
/** @var array Map of rules to the non-terminal on their left-hand side, i.e. the non-terminal to use for
* determining the state to goto after reduction. */
protected $ruleToNonTerminal;
/** @var array Map of rules to the length of their right-hand side, which is the number of elements that have to
* be popped from the stack(s) on reduction. */
protected $ruleToLength;
/*
* The following members are part of the parser state:
*/
/** @var Lexer Lexer that is used when parsing */
protected $lexer;
/** @var mixed Temporary value containing the result of last semantic action (reduction) */
protected $semValue;
/** @var int Position in stacks (state stack, semantic value stack, attribute stack) */
protected $stackPos;
/** @var array Semantic value stack (contains values of tokens and semantic action results) */
protected $semStack;
/** @var array[] Start attribute stack */
protected $startAttributeStack;
/** @var array[] End attribute stack */
protected $endAttributeStack;
/** @var array End attributes of last *shifted* token */
protected $endAttributes;
/** @var array Start attributes of last *read* token */
protected $lookaheadStartAttributes;
/** @var ErrorHandler Error handler */
protected $errorHandler;
/** @var Error[] Errors collected during last parse */
protected $errors;
/** @var int Error state, used to avoid error floods */
protected $errorState;
/** @var bool Whether to create Identifier nodes for non-namespaced names */
protected $useIdentifierNodes;
/** @var bool Whether to consistently use Variable nodes */
protected $useConsistentVariableNodes;
/**
* Creates a parser instance.
*
* Options:
* * useIdentifierNodes: If this option is enabled, the parser will create Identifier nodes for
* non-namespaced names. Otherwise plain strings will be used.
* * useConsistentVariableNodes: If this option is enabled, the parser will create Variable
* nodes in more places (like function parameters, catch clause variables, etc.)
*
* @param Lexer $lexer A lexer
* @param array $options Options array.
*/
public function __construct(Lexer $lexer, array $options = array()) {
$this->lexer = $lexer;
$this->errors = array();
$this->useIdentifierNodes = !empty($options['useIdentifierNodes']);
$this->useConsistentVariableNodes = !empty($options['useConsistentVariableNodes']);
if (isset($options['throwOnError'])) {
throw new \LogicException(
'"throwOnError" is no longer supported, use "errorHandler" instead');
}
}
/**
* Parses PHP code into a node tree.
*
* If a non-throwing error handler is used, the parser will continue parsing after an error
* occurred and attempt to build a partial AST.
*
* @param string $code The source code to parse
* @param ErrorHandler|null $errorHandler Error handler to use for lexer/parser errors, defaults
* to ErrorHandler\Throwing.
*
* @return Node[]|null Array of statements (or null if the 'throwOnError' option is disabled and the parser was
* unable to recover from an error).
*/
public function parse($code, ErrorHandler $errorHandler = null) {
$this->errorHandler = $errorHandler ?: new ErrorHandler\Throwing;
// Initialize the lexer
$this->lexer->startLexing($code, $this->errorHandler);
// We start off with no lookahead-token
$symbol = self::SYMBOL_NONE;
// The attributes for a node are taken from the first and last token of the node.
// From the first token only the startAttributes are taken and from the last only
// the endAttributes. Both are merged using the array union operator (+).
$startAttributes = '*POISON';
$endAttributes = '*POISON';
$this->endAttributes = $endAttributes;
// Keep stack of start and end attributes
$this->startAttributeStack = array();
$this->endAttributeStack = array($endAttributes);
// Start off in the initial state and keep a stack of previous states
$state = 0;
$stateStack = array($state);
// Semantic value stack (contains values of tokens and semantic action results)
$this->semStack = array();
// Current position in the stack(s)
$this->stackPos = 0;
$this->errorState = 0;
for (;;) {
//$this->traceNewState($state, $symbol);
if ($this->actionBase[$state] == 0) {
$rule = $this->actionDefault[$state];
} else {
if ($symbol === self::SYMBOL_NONE) {
// Fetch the next token id from the lexer and fetch additional info by-ref.
// The end attributes are fetched into a temporary variable and only set once the token is really
// shifted (not during read). Otherwise you would sometimes get off-by-one errors, when a rule is
// reduced after a token was read but not yet shifted.
$tokenId = $this->lexer->getNextToken($tokenValue, $startAttributes, $endAttributes);
// map the lexer token id to the internally used symbols
$symbol = $tokenId >= 0 && $tokenId < $this->tokenToSymbolMapSize
? $this->tokenToSymbol[$tokenId]
: $this->invalidSymbol;
if ($symbol === $this->invalidSymbol) {
throw new \RangeException(sprintf(
'The lexer returned an invalid token (id=%d, value=%s)',
$tokenId, $tokenValue
));
}
// This is necessary to assign some meaningful attributes to /* empty */ productions. They'll get
// the attributes of the next token, even though they don't contain it themselves.
$this->startAttributeStack[$this->stackPos+1] = $startAttributes;
$this->endAttributeStack[$this->stackPos+1] = $endAttributes;
$this->lookaheadStartAttributes = $startAttributes;
//$this->traceRead($symbol);
}
$idx = $this->actionBase[$state] + $symbol;
if ((($idx >= 0 && $idx < $this->actionTableSize && $this->actionCheck[$idx] == $symbol)
|| ($state < $this->YY2TBLSTATE
&& ($idx = $this->actionBase[$state + $this->YYNLSTATES] + $symbol) >= 0
&& $idx < $this->actionTableSize && $this->actionCheck[$idx] == $symbol))
&& ($action = $this->action[$idx]) != $this->defaultAction) {
/*
* >= YYNLSTATES: shift and reduce
* > 0: shift
* = 0: accept
* < 0: reduce
* = -YYUNEXPECTED: error
*/
if ($action > 0) {
/* shift */
//$this->traceShift($symbol);
++$this->stackPos;
$stateStack[$this->stackPos] = $state = $action;
$this->semStack[$this->stackPos] = $tokenValue;
$this->startAttributeStack[$this->stackPos] = $startAttributes;
$this->endAttributeStack[$this->stackPos] = $endAttributes;
$this->endAttributes = $endAttributes;
$symbol = self::SYMBOL_NONE;
if ($this->errorState) {
--$this->errorState;
}
if ($action < $this->YYNLSTATES) {
continue;
}
/* $yyn >= YYNLSTATES means shift-and-reduce */
$rule = $action - $this->YYNLSTATES;
} else {
$rule = -$action;
}
} else {
$rule = $this->actionDefault[$state];
}
}
for (;;) {
if ($rule === 0) {
/* accept */
//$this->traceAccept();
return $this->semValue;
} elseif ($rule !== $this->unexpectedTokenRule) {
/* reduce */
//$this->traceReduce($rule);
try {
$this->{'reduceRule' . $rule}();
} catch (Error $e) {
if (-1 === $e->getStartLine() && isset($startAttributes['startLine'])) {
$e->setStartLine($startAttributes['startLine']);
}
$this->emitError($e);
// Can't recover from this type of error
return null;
}
/* Goto - shift nonterminal */
$lastEndAttributes = $this->endAttributeStack[$this->stackPos];
$this->stackPos -= $this->ruleToLength[$rule];
$nonTerminal = $this->ruleToNonTerminal[$rule];
$idx = $this->gotoBase[$nonTerminal] + $stateStack[$this->stackPos];
if ($idx >= 0 && $idx < $this->gotoTableSize && $this->gotoCheck[$idx] == $nonTerminal) {
$state = $this->goto[$idx];
} else {
$state = $this->gotoDefault[$nonTerminal];
}
++$this->stackPos;
$stateStack[$this->stackPos] = $state;
$this->semStack[$this->stackPos] = $this->semValue;
$this->endAttributeStack[$this->stackPos] = $lastEndAttributes;
} else {
/* error */
switch ($this->errorState) {
case 0:
$msg = $this->getErrorMessage($symbol, $state);
$this->emitError(new Error($msg, $startAttributes + $endAttributes));
// Break missing intentionally
case 1:
case 2:
$this->errorState = 3;
// Pop until error-expecting state uncovered
while (!(
(($idx = $this->actionBase[$state] + $this->errorSymbol) >= 0
&& $idx < $this->actionTableSize && $this->actionCheck[$idx] == $this->errorSymbol)
|| ($state < $this->YY2TBLSTATE
&& ($idx = $this->actionBase[$state + $this->YYNLSTATES] + $this->errorSymbol) >= 0
&& $idx < $this->actionTableSize && $this->actionCheck[$idx] == $this->errorSymbol)
) || ($action = $this->action[$idx]) == $this->defaultAction) { // Not totally sure about this
if ($this->stackPos <= 0) {
// Could not recover from error
return null;
}
$state = $stateStack[--$this->stackPos];
//$this->tracePop($state);
}
//$this->traceShift($this->errorSymbol);
++$this->stackPos;
$stateStack[$this->stackPos] = $state = $action;
$this->endAttributes = $this->endAttributeStack[$this->stackPos];
break;
case 3:
if ($symbol === 0) {
// Reached EOF without recovering from error
return null;
}
//$this->traceDiscard($symbol);
$symbol = self::SYMBOL_NONE;
break 2;
}
}
if ($state < $this->YYNLSTATES) {
break;
}
/* >= YYNLSTATES means shift-and-reduce */
$rule = $state - $this->YYNLSTATES;
}
}
throw new \RuntimeException('Reached end of parser loop');
}
protected function emitError(Error $error) {
$this->errorHandler->handleError($error);
}
protected function getErrorMessage($symbol, $state) {
$expectedString = '';
if ($expected = $this->getExpectedTokens($state)) {
$expectedString = ', expecting ' . implode(' or ', $expected);
}
return 'Syntax error, unexpected ' . $this->symbolToName[$symbol] . $expectedString;
}
protected function getExpectedTokens($state) {
$expected = array();
$base = $this->actionBase[$state];
foreach ($this->symbolToName as $symbol => $name) {
$idx = $base + $symbol;
if ($idx >= 0 && $idx < $this->actionTableSize && $this->actionCheck[$idx] === $symbol
|| $state < $this->YY2TBLSTATE
&& ($idx = $this->actionBase[$state + $this->YYNLSTATES] + $symbol) >= 0
&& $idx < $this->actionTableSize && $this->actionCheck[$idx] === $symbol
) {
if ($this->action[$idx] != $this->unexpectedTokenRule
&& $this->action[$idx] != $this->defaultAction
&& $symbol != $this->errorSymbol
) {
if (count($expected) == 4) {
/* Too many expected tokens */
return array();
}
$expected[] = $name;
}
}
}
return $expected;
}
/*
* Tracing functions used for debugging the parser.
*/
/*
protected function traceNewState($state, $symbol) {
echo '% State ' . $state
. ', Lookahead ' . ($symbol == self::SYMBOL_NONE ? '--none--' : $this->symbolToName[$symbol]) . "\n";
}
protected function traceRead($symbol) {
echo '% Reading ' . $this->symbolToName[$symbol] . "\n";
}
protected function traceShift($symbol) {
echo '% Shift ' . $this->symbolToName[$symbol] . "\n";
}
protected function traceAccept() {
echo "% Accepted.\n";
}
protected function traceReduce($n) {
echo '% Reduce by (' . $n . ') ' . $this->productions[$n] . "\n";
}
protected function tracePop($state) {
echo '% Recovering, uncovered state ' . $state . "\n";
}
protected function traceDiscard($symbol) {
echo '% Discard ' . $this->symbolToName[$symbol] . "\n";
}
*/
/*
* Helper functions invoked by semantic actions
*/
/**
* Moves statements of semicolon-style namespaces into $ns->stmts and checks various error conditions.
*
* @param Node[] $stmts
* @return Node[]
*/
protected function handleNamespaces(array $stmts) {
$hasErrored = false;
$style = $this->getNamespacingStyle($stmts);
if (null === $style) {
// not namespaced, nothing to do
return $stmts;
} elseif ('brace' === $style) {
// For braced namespaces we only have to check that there are no invalid statements between the namespaces
$afterFirstNamespace = false;
foreach ($stmts as $stmt) {
if ($stmt instanceof Node\Stmt\Namespace_) {
$afterFirstNamespace = true;
} elseif (!$stmt instanceof Node\Stmt\HaltCompiler
&& $afterFirstNamespace && !$hasErrored) {
$this->emitError(new Error(
'No code may exist outside of namespace {}', $stmt->getAttributes()));
$hasErrored = true; // Avoid one error for every statement
}
}
return $stmts;
} else {
// For semicolon namespaces we have to move the statements after a namespace declaration into ->stmts
$resultStmts = array();
$targetStmts =& $resultStmts;
foreach ($stmts as $stmt) {
if ($stmt instanceof Node\Stmt\Namespace_) {
if ($stmt->stmts === null) {
$stmt->stmts = array();
$targetStmts =& $stmt->stmts;
$resultStmts[] = $stmt;
} else {
// This handles the invalid case of mixed style namespaces
$resultStmts[] = $stmt;
$targetStmts =& $resultStmts;
}
} elseif ($stmt instanceof Node\Stmt\HaltCompiler) {
// __halt_compiler() is not moved into the namespace
$resultStmts[] = $stmt;
} else {
$targetStmts[] = $stmt;
}
}
return $resultStmts;
}
}
private function getNamespacingStyle(array $stmts) {
$style = null;
$hasNotAllowedStmts = false;
foreach ($stmts as $i => $stmt) {
if ($stmt instanceof Node\Stmt\Namespace_) {
$currentStyle = null === $stmt->stmts ? 'semicolon' : 'brace';
if (null === $style) {
$style = $currentStyle;
if ($hasNotAllowedStmts) {
$this->emitError(new Error(
'Namespace declaration statement has to be the very first statement in the script',
$stmt->getLine() // Avoid marking the entire namespace as an error
));
}
} elseif ($style !== $currentStyle) {
$this->emitError(new Error(
'Cannot mix bracketed namespace declarations with unbracketed namespace declarations',
$stmt->getLine() // Avoid marking the entire namespace as an error
));
// Treat like semicolon style for namespace normalization
return 'semicolon';
}
continue;
}
/* declare(), __halt_compiler() and nops can be used before a namespace declaration */
if ($stmt instanceof Node\Stmt\Declare_
|| $stmt instanceof Node\Stmt\HaltCompiler
|| $stmt instanceof Node\Stmt\Nop) {
continue;
}
/* There may be a hashbang line at the very start of the file */
if ($i == 0 && $stmt instanceof Node\Stmt\InlineHTML && preg_match('/\A#!.*\r?\n\z/', $stmt->value)) {
continue;
}
/* Everything else if forbidden before namespace declarations */
$hasNotAllowedStmts = true;
}
return $style;
}
protected function handleBuiltinTypes(Name $name) {
$scalarTypes = [
'bool' => true,
'int' => true,
'float' => true,
'string' => true,
'iterable' => true,
'void' => true,
];
if (!$name->isUnqualified()) {
return $name;
}
$lowerName = strtolower($name->toString());
if (!isset($scalarTypes[$lowerName])) {
return $name;
}
return $this->useIdentifierNodes
? new Node\Identifier($lowerName, $name->getAttributes())
: $lowerName;
}
protected static $specialNames = array(
'self' => true,
'parent' => true,
'static' => true,
);
protected function getAttributesAt($pos) {
return $this->startAttributeStack[$pos] + $this->endAttributeStack[$pos];
}
protected function parseLNumber($str, $attributes, $allowInvalidOctal = false) {
try {
return LNumber::fromString($str, $attributes, $allowInvalidOctal);
} catch (Error $error) {
$this->emitError($error);
// Use dummy value
return new LNumber(0, $attributes);
}
}
protected function parseNumString($str, $attributes) {
if (!preg_match('/^(?:0|-?[1-9][0-9]*)$/', $str)) {
return new String_($str, $attributes);
}
$num = +$str;
if (!is_int($num)) {
return new String_($str, $attributes);
}
return new LNumber($num, $attributes);
}
protected function checkModifier($a, $b, $modifierPos) {
// Jumping through some hoops here because verifyModifier() is also used elsewhere
try {
Class_::verifyModifier($a, $b);
} catch (Error $error) {
$error->setAttributes($this->getAttributesAt($modifierPos));
$this->emitError($error);
}
}
protected function checkParam(Param $node) {
if ($node->variadic && null !== $node->default) {
$this->emitError(new Error(
'Variadic parameter cannot have a default value',
$node->default->getAttributes()
));
}
}
protected function checkTryCatch(TryCatch $node) {
if (empty($node->catches) && null === $node->finally) {
$this->emitError(new Error(
'Cannot use try without catch or finally', $node->getAttributes()
));
}
}
protected function checkNamespace(Namespace_ $node) {
if (isset(self::$specialNames[strtolower($node->name)])) {
$this->emitError(new Error(
sprintf('Cannot use \'%s\' as namespace name', $node->name),
$node->name->getAttributes()
));
}
if (null !== $node->stmts) {
foreach ($node->stmts as $stmt) {
if ($stmt instanceof Namespace_) {
$this->emitError(new Error(
'Namespace declarations cannot be nested', $stmt->getAttributes()
));
}
}
}
}
protected function checkClass(Class_ $node, $namePos) {
if (null !== $node->name && isset(self::$specialNames[strtolower($node->name)])) {
$this->emitError(new Error(
sprintf('Cannot use \'%s\' as class name as it is reserved', $node->name),
$this->getAttributesAt($namePos)
));
}
if (isset(self::$specialNames[strtolower($node->extends)])) {
$this->emitError(new Error(
sprintf('Cannot use \'%s\' as class name as it is reserved', $node->extends),
$node->extends->getAttributes()
));
}
foreach ($node->implements as $interface) {
if (isset(self::$specialNames[strtolower($interface)])) {
$this->emitError(new Error(
sprintf('Cannot use \'%s\' as interface name as it is reserved', $interface),
$interface->getAttributes()
));
}
}
}
protected function checkInterface(Interface_ $node, $namePos) {
if (null !== $node->name && isset(self::$specialNames[strtolower($node->name)])) {
$this->emitError(new Error(
sprintf('Cannot use \'%s\' as class name as it is reserved', $node->name),
$this->getAttributesAt($namePos)
));
}
foreach ($node->extends as $interface) {
if (isset(self::$specialNames[strtolower($interface)])) {
$this->emitError(new Error(
sprintf('Cannot use \'%s\' as interface name as it is reserved', $interface),
$interface->getAttributes()
));
}
}
}
protected function checkClassMethod(ClassMethod $node, $modifierPos) {
if ($node->flags & Class_::MODIFIER_STATIC) {
switch (strtolower($node->name)) {
case '__construct':
$this->emitError(new Error(
sprintf('Constructor %s() cannot be static', $node->name),
$this->getAttributesAt($modifierPos)));
break;
case '__destruct':
$this->emitError(new Error(
sprintf('Destructor %s() cannot be static', $node->name),
$this->getAttributesAt($modifierPos)));
break;
case '__clone':
$this->emitError(new Error(
sprintf('Clone method %s() cannot be static', $node->name),
$this->getAttributesAt($modifierPos)));
break;
}
}
}
protected function checkClassConst(ClassConst $node, $modifierPos) {
if ($node->flags & Class_::MODIFIER_STATIC) {
$this->emitError(new Error(
"Cannot use 'static' as constant modifier",
$this->getAttributesAt($modifierPos)));
}
if ($node->flags & Class_::MODIFIER_ABSTRACT) {
$this->emitError(new Error(
"Cannot use 'abstract' as constant modifier",
$this->getAttributesAt($modifierPos)));
}
if ($node->flags & Class_::MODIFIER_FINAL) {
$this->emitError(new Error(
"Cannot use 'final' as constant modifier",
$this->getAttributesAt($modifierPos)));
}
}
protected function checkProperty(Property $node, $modifierPos) {
if ($node->flags & Class_::MODIFIER_ABSTRACT) {
$this->emitError(new Error('Properties cannot be declared abstract',
$this->getAttributesAt($modifierPos)));
}
if ($node->flags & Class_::MODIFIER_FINAL) {
$this->emitError(new Error('Properties cannot be declared final',
$this->getAttributesAt($modifierPos)));
}
}
protected function checkUseUse(UseUse $node, $namePos) {
if ('self' == strtolower($node->alias) || 'parent' == strtolower($node->alias)) {
$this->emitError(new Error(
sprintf(
'Cannot use %s as %s because \'%2$s\' is a special class name',
$node->name, $node->alias
),
$this->getAttributesAt($namePos)
));
}
}
}