blob: bc237a1f4f40b65874a588a3bf489041b93c6af0 [file] [log] [blame]
/*
* Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2003-2019 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#pragma once
#include "ExecutableInfo.h"
#include "Lexer.h"
#include "ModuleScopeData.h"
#include "Nodes.h"
#include "ParseHash.h"
#include "ParserArena.h"
#include "ParserError.h"
#include "ParserFunctionInfo.h"
#include "ParserTokens.h"
#include "SourceProvider.h"
#include "SourceProviderCache.h"
#include "SourceProviderCacheItem.h"
#include "VariableEnvironment.h"
#include <wtf/FixedVector.h>
#include <wtf/Forward.h>
#include <wtf/IterationStatus.h>
#include <wtf/Noncopyable.h>
#include <wtf/RefPtr.h>
namespace JSC {
class FunctionMetadataNode;
class FunctionParameters;
class Identifier;
class VM;
class SourceCode;
class SyntaxChecker;
struct DebuggerParseData;
// Macros to make the more common TreeBuilder types a little less verbose
#define TreeStatement typename TreeBuilder::Statement
#define TreeExpression typename TreeBuilder::Expression
#define TreeFormalParameterList typename TreeBuilder::FormalParameterList
#define TreeSourceElements typename TreeBuilder::SourceElements
#define TreeClause typename TreeBuilder::Clause
#define TreeClauseList typename TreeBuilder::ClauseList
#define TreeArguments typename TreeBuilder::Arguments
#define TreeArgumentsList typename TreeBuilder::ArgumentsList
#define TreeFunctionBody typename TreeBuilder::FunctionBody
#define TreeClassExpression typename TreeBuilder::ClassExpression
#define TreeProperty typename TreeBuilder::Property
#define TreePropertyList typename TreeBuilder::PropertyList
#define TreeDestructuringPattern typename TreeBuilder::DestructuringPattern
static_assert(LastUntaggedToken < 64, "Less than 64 untagged tokens");
enum SourceElementsMode { CheckForStrictMode, DontCheckForStrictMode };
enum FunctionBodyType { ArrowFunctionBodyExpression, ArrowFunctionBodyBlock, StandardFunctionBodyBlock };
enum class FunctionNameRequirements { None, Named, Unnamed };
enum class DestructuringKind {
DestructureToVariables,
DestructureToLet,
DestructureToConst,
DestructureToCatchParameters,
DestructureToParameters,
DestructureToExpressions
};
enum class DeclarationType {
VarDeclaration,
LetDeclaration,
ConstDeclaration
};
enum class DeclarationImportType {
Imported,
ImportedNamespace,
NotImported
};
enum DeclarationResult {
Valid = 0,
InvalidStrictMode = 1 << 0,
InvalidDuplicateDeclaration = 1 << 1,
InvalidPrivateStaticNonStatic = 1 << 2
};
typedef uint8_t DeclarationResultMask;
enum class DeclarationDefaultContext {
Standard,
ExportDefault,
};
enum class InferName {
Allowed,
Disallowed,
};
template <typename T> inline bool isEvalNode() { return false; }
template <> inline bool isEvalNode<EvalNode>() { return true; }
struct ScopeLabelInfo {
UniquedStringImpl* uid;
bool isLoop;
};
ALWAYS_INLINE static bool isArguments(const VM& vm, const Identifier* ident)
{
return vm.propertyNames->arguments == *ident;
}
ALWAYS_INLINE static bool isEval(const VM& vm, const Identifier* ident)
{
return vm.propertyNames->eval == *ident;
}
ALWAYS_INLINE static bool isEvalOrArgumentsIdentifier(const VM& vm, const Identifier* ident)
{
return isEval(vm, ident) || isArguments(vm, ident);
}
ALWAYS_INLINE static bool isIdentifierOrKeyword(const JSToken& token)
{
return token.m_type == IDENT || token.m_type & KeywordTokenFlag;
}
// "let", "yield", and "await" may be keywords or identifiers depending on context.
ALWAYS_INLINE static bool isContextualKeyword(const JSToken& token)
{
return token.m_type >= FirstContextualKeywordToken && token.m_type <= LastContextualKeywordToken;
}
JS_EXPORT_PRIVATE extern std::atomic<unsigned> globalParseCount;
struct Scope {
WTF_MAKE_NONCOPYABLE(Scope);
public:
Scope(const VM& vm, LexicalScopeFeatures lexicalScopeFeatures, bool isFunction, bool isGenerator, bool isArrowFunction, bool isAsyncFunction)
: m_vm(vm)
, m_shadowsArguments(false)
, m_usesEval(false)
, m_needsFullActivation(false)
, m_hasDirectSuper(false)
, m_needsSuperBinding(false)
, m_allowsVarDeclarations(true)
, m_allowsLexicalDeclarations(true)
, m_lexicalScopeFeatures(lexicalScopeFeatures)
, m_isFunction(isFunction)
, m_isGenerator(isGenerator)
, m_isGeneratorBoundary(false)
, m_isArrowFunction(isArrowFunction)
, m_isArrowFunctionBoundary(false)
, m_isAsyncFunction(isAsyncFunction)
, m_isAsyncFunctionBoundary(false)
, m_isLexicalScope(false)
, m_isGlobalCodeScope(false)
, m_isSimpleCatchParameterScope(false)
, m_isCatchBlockScope(false)
, m_isFunctionBoundary(false)
, m_isValidStrictMode(true)
, m_hasArguments(false)
, m_isEvalContext(false)
, m_hasNonSimpleParameterList(false)
, m_isClassScope(false)
, m_evalContextType(EvalContextType::None)
, m_constructorKind(static_cast<unsigned>(ConstructorKind::None))
, m_expectedSuperBinding(static_cast<unsigned>(SuperBinding::NotNeeded))
, m_loopDepth(0)
, m_switchDepth(0)
, m_innerArrowFunctionFeatures(0)
{
m_usedVariables.append(UniquedStringImplPtrSet());
}
Scope(Scope&&) = default;
void startSwitch() { m_switchDepth++; }
void endSwitch() { m_switchDepth--; }
void startLoop() { m_loopDepth++; }
void endLoop() { ASSERT(m_loopDepth); m_loopDepth--; }
bool inLoop() { return !!m_loopDepth; }
bool breakIsValid() { return m_loopDepth || m_switchDepth; }
bool continueIsValid() { return m_loopDepth; }
void pushLabel(const Identifier* label, bool isLoop)
{
if (!m_labels)
m_labels = makeUnique<LabelStack>();
m_labels->append(ScopeLabelInfo { label->impl(), isLoop });
}
void popLabel()
{
ASSERT(m_labels);
ASSERT(m_labels->size());
m_labels->removeLast();
}
ScopeLabelInfo* getLabel(const Identifier* label)
{
if (!m_labels)
return nullptr;
for (int i = m_labels->size(); i > 0; i--) {
if (m_labels->at(i - 1).uid == label->impl())
return &m_labels->at(i - 1);
}
return nullptr;
}
void setSourceParseMode(SourceParseMode mode)
{
switch (mode) {
case SourceParseMode::AsyncGeneratorBodyMode:
setIsAsyncGeneratorFunctionBody();
break;
case SourceParseMode::AsyncArrowFunctionBodyMode:
setIsAsyncArrowFunctionBody();
break;
case SourceParseMode::AsyncFunctionBodyMode:
setIsAsyncFunctionBody();
break;
case SourceParseMode::GeneratorBodyMode:
setIsGenerator();
break;
case SourceParseMode::GeneratorWrapperFunctionMode:
case SourceParseMode::GeneratorWrapperMethodMode:
setIsGeneratorFunction();
break;
case SourceParseMode::AsyncGeneratorWrapperMethodMode:
case SourceParseMode::AsyncGeneratorWrapperFunctionMode:
setIsAsyncGeneratorFunction();
break;
case SourceParseMode::NormalFunctionMode:
case SourceParseMode::GetterMode:
case SourceParseMode::SetterMode:
case SourceParseMode::MethodMode:
case SourceParseMode::ClassFieldInitializerMode:
setIsFunction();
break;
case SourceParseMode::ArrowFunctionMode:
setIsArrowFunction();
break;
case SourceParseMode::AsyncFunctionMode:
case SourceParseMode::AsyncMethodMode:
setIsAsyncFunction();
break;
case SourceParseMode::AsyncArrowFunctionMode:
setIsAsyncArrowFunction();
break;
case SourceParseMode::ProgramMode:
case SourceParseMode::ModuleAnalyzeMode:
case SourceParseMode::ModuleEvaluateMode:
break;
}
}
bool isFunction() const { return m_isFunction; }
bool isFunctionBoundary() const { return m_isFunctionBoundary; }
bool isGenerator() const { return m_isGenerator; }
bool isGeneratorBoundary() const { return m_isGeneratorBoundary; }
bool isAsyncFunction() const { return m_isAsyncFunction; }
bool isAsyncFunctionBoundary() const { return m_isAsyncFunctionBoundary; }
bool isPrivateNameScope() const { return m_isClassScope; }
bool isClassScope() const { return m_isClassScope; }
bool hasArguments() const { return m_hasArguments; }
void setIsGlobalCodeScope() { m_isGlobalCodeScope = true; }
bool isGlobalCodeScope() const { return m_isGlobalCodeScope; }
void setIsSimpleCatchParameterScope() { m_isSimpleCatchParameterScope = true; }
bool isSimpleCatchParameterScope() { return m_isSimpleCatchParameterScope; }
void setIsCatchBlockScope() { m_isCatchBlockScope = true; }
bool isCatchBlockScope() { return m_isCatchBlockScope; }
void setIsLexicalScope()
{
m_isLexicalScope = true;
m_allowsLexicalDeclarations = true;
}
void setIsPrivateNameScope()
{
// FIXME: Currently, isPrivateNameScope is an alias for isClassScope --- This is potentially misleading,
// particularly when parsing direct eval code which occurs within a class.
setIsClassScope();
}
void setIsClassScope()
{
m_isClassScope = true;
}
bool isLexicalScope() { return m_isLexicalScope; }
bool usesEval() { return m_usesEval; }
const HashSet<UniquedStringImpl*>& closedVariableCandidates() const { return m_closedVariableCandidates; }
VariableEnvironment& declaredVariables() { return m_declaredVariables; }
VariableEnvironment& lexicalVariables() { return m_lexicalVariables; }
void finalizeLexicalEnvironment()
{
if (m_usesEval || m_needsFullActivation)
m_lexicalVariables.markAllVariablesAsCaptured();
else
computeLexicallyCapturedVariablesAndPurgeCandidates();
}
VariableEnvironment takeLexicalEnvironment() { return WTFMove(m_lexicalVariables); }
VariableEnvironment takeDeclaredVariables() { return WTFMove(m_declaredVariables); }
void computeLexicallyCapturedVariablesAndPurgeCandidates()
{
// Because variables may be defined at any time in the range of a lexical scope, we must
// track lexical variables that might be captured. Then, when we're preparing to pop the top
// lexical scope off the stack, we should find which variables are truly captured, and which
// variable still may be captured in a parent scope.
if (m_lexicalVariables.size() && m_closedVariableCandidates.size()) {
for (UniquedStringImpl* impl : m_closedVariableCandidates)
m_lexicalVariables.markVariableAsCapturedIfDefined(impl);
}
// We can now purge values from the captured candidates because they're captured in this scope.
{
for (const auto& entry : m_lexicalVariables) {
if (entry.value.isCaptured())
m_closedVariableCandidates.remove(entry.key.get());
}
}
}
DeclarationResultMask declareCallee(const Identifier* ident)
{
auto addResult = m_declaredVariables.add(ident->impl());
// We want to track if callee is captured, but we don't want to act like it's a 'var'
// because that would cause the BytecodeGenerator to emit bad code.
addResult.iterator->value.clearIsVar();
DeclarationResultMask result = DeclarationResult::Valid;
if (isEvalOrArgumentsIdentifier(m_vm, ident))
result |= DeclarationResult::InvalidStrictMode;
return result;
}
DeclarationResultMask declareVariable(const Identifier* ident)
{
ASSERT(m_allowsVarDeclarations);
DeclarationResultMask result = DeclarationResult::Valid;
bool isValidStrictMode = !isEvalOrArgumentsIdentifier(m_vm, ident);
m_isValidStrictMode = m_isValidStrictMode && isValidStrictMode;
auto addResult = m_declaredVariables.add(ident->impl());
addResult.iterator->value.setIsVar();
if (!isValidStrictMode)
result |= DeclarationResult::InvalidStrictMode;
return result;
}
DeclarationResultMask declareFunction(const Identifier* ident, bool declareAsVar, bool isSloppyModeHoistingCandidate)
{
ASSERT(m_allowsVarDeclarations || m_allowsLexicalDeclarations);
DeclarationResultMask result = DeclarationResult::Valid;
bool isValidStrictMode = !isEvalOrArgumentsIdentifier(m_vm, ident);
if (!isValidStrictMode)
result |= DeclarationResult::InvalidStrictMode;
m_isValidStrictMode = m_isValidStrictMode && isValidStrictMode;
auto addResult = declareAsVar ? m_declaredVariables.add(ident->impl()) : m_lexicalVariables.add(ident->impl());
if (isSloppyModeHoistingCandidate)
addResult.iterator->value.setIsSloppyModeHoistingCandidate();
if (declareAsVar) {
addResult.iterator->value.setIsVar();
if (m_lexicalVariables.contains(ident->impl()))
result |= DeclarationResult::InvalidDuplicateDeclaration;
} else {
addResult.iterator->value.setIsLet();
ASSERT_WITH_MESSAGE(!m_declaredVariables.size(), "We should only declare a function as a lexically scoped variable in scopes where var declarations aren't allowed. I.e, in strict mode and not at the top-level scope of a function or program.");
if (!addResult.isNewEntry) {
if (!isSloppyModeHoistingCandidate || !addResult.iterator->value.isFunction())
result |= DeclarationResult::InvalidDuplicateDeclaration;
}
}
addResult.iterator->value.setIsFunction();
return result;
}
void addVariableBeingHoisted(const Identifier* ident)
{
ASSERT(!m_allowsVarDeclarations);
m_variablesBeingHoisted.add(ident->impl());
}
void addSloppyModeHoistableFunctionCandidate(const Identifier* ident)
{
ASSERT(m_allowsVarDeclarations);
m_sloppyModeHoistableFunctionCandidates.add(ident->impl());
}
void appendFunction(FunctionMetadataNode* node)
{
ASSERT(node);
m_functionDeclarations.append(node);
}
DeclarationStacks::FunctionStack takeFunctionDeclarations() { return WTFMove(m_functionDeclarations); }
DeclarationResultMask declareLexicalVariable(const Identifier* ident, bool isConstant, DeclarationImportType importType = DeclarationImportType::NotImported)
{
ASSERT(m_allowsLexicalDeclarations);
DeclarationResultMask result = DeclarationResult::Valid;
bool isValidStrictMode = !isEvalOrArgumentsIdentifier(m_vm, ident);
m_isValidStrictMode = m_isValidStrictMode && isValidStrictMode;
auto addResult = m_lexicalVariables.add(ident->impl());
if (isConstant)
addResult.iterator->value.setIsConst();
else
addResult.iterator->value.setIsLet();
if (importType == DeclarationImportType::Imported)
addResult.iterator->value.setIsImported();
else if (importType == DeclarationImportType::ImportedNamespace) {
addResult.iterator->value.setIsImported();
addResult.iterator->value.setIsImportedNamespace();
}
if (!addResult.isNewEntry || m_variablesBeingHoisted.contains(ident->impl()))
result |= DeclarationResult::InvalidDuplicateDeclaration;
if (!isValidStrictMode)
result |= DeclarationResult::InvalidStrictMode;
return result;
}
ALWAYS_INLINE bool hasDeclaredVariable(const Identifier& ident)
{
return hasDeclaredVariable(ident.impl());
}
bool hasDeclaredVariable(const RefPtr<UniquedStringImpl>& ident)
{
auto iter = m_declaredVariables.find(ident.get());
if (iter == m_declaredVariables.end())
return false;
VariableEnvironmentEntry entry = iter->value;
return entry.isVar(); // The callee isn't a "var".
}
ALWAYS_INLINE bool hasLexicallyDeclaredVariable(const Identifier& ident)
{
return hasLexicallyDeclaredVariable(ident.impl());
}
bool hasLexicallyDeclaredVariable(const RefPtr<UniquedStringImpl>& ident) const
{
return m_lexicalVariables.contains(ident.get());
}
bool hasPrivateName(const Identifier& ident)
{
return m_lexicalVariables.hasPrivateName(ident);
}
DeclarationResultMask declarePrivateMethod(const Identifier& ident, ClassElementTag tag)
{
ASSERT(m_allowsLexicalDeclarations);
DeclarationResultMask result = DeclarationResult::Valid;
bool addResult = tag == ClassElementTag::Static ? m_lexicalVariables.declareStaticPrivateMethod(ident) : m_lexicalVariables.declarePrivateMethod(ident);
if (!addResult) {
result |= DeclarationResult::InvalidDuplicateDeclaration;
return result;
}
return result;
}
enum class PrivateAccessorType { Setter, Getter };
DeclarationResultMask declarePrivateAccessor(const Identifier& ident, ClassElementTag tag, PrivateAccessorType accessorType)
{
DeclarationResultMask result = DeclarationResult::Valid;
VariableEnvironment::PrivateDeclarationResult addResult;
if (accessorType == PrivateAccessorType::Setter)
addResult = tag == ClassElementTag::Static ? m_lexicalVariables.declareStaticPrivateSetter(ident) : m_lexicalVariables.declarePrivateSetter(ident);
else
addResult = tag == ClassElementTag::Static ? m_lexicalVariables.declareStaticPrivateGetter(ident) : m_lexicalVariables.declarePrivateGetter(ident);
if (addResult == VariableEnvironment::PrivateDeclarationResult::DuplicatedName)
result |= DeclarationResult::InvalidDuplicateDeclaration;
if (addResult == VariableEnvironment::PrivateDeclarationResult::InvalidStaticNonStatic)
result |= DeclarationResult::InvalidPrivateStaticNonStatic;
return result;
}
DeclarationResultMask declarePrivateSetter(const Identifier& ident, ClassElementTag tag)
{
ASSERT(m_allowsLexicalDeclarations);
return declarePrivateAccessor(ident, tag, PrivateAccessorType::Setter);
}
DeclarationResultMask declarePrivateGetter(const Identifier& ident, ClassElementTag tag)
{
ASSERT(m_allowsLexicalDeclarations);
return declarePrivateAccessor(ident, tag, PrivateAccessorType::Getter);
}
DeclarationResultMask declarePrivateField(const Identifier& ident)
{
ASSERT(m_allowsLexicalDeclarations);
DeclarationResultMask result = DeclarationResult::Valid;
auto addResult = m_lexicalVariables.declarePrivateField(ident);
if (!addResult.isNewEntry)
result |= DeclarationResult::InvalidDuplicateDeclaration;
return result;
}
ALWAYS_INLINE bool hasDeclaredParameter(const Identifier& ident)
{
return hasDeclaredParameter(ident.impl());
}
bool hasDeclaredParameter(const RefPtr<UniquedStringImpl>& ident)
{
return m_declaredParameters.contains(ident.get()) || hasDeclaredVariable(ident);
}
void preventAllVariableDeclarations()
{
m_allowsVarDeclarations = false;
m_allowsLexicalDeclarations = false;
}
void preventVarDeclarations() { m_allowsVarDeclarations = false; }
bool allowsVarDeclarations() const { return m_allowsVarDeclarations; }
bool allowsLexicalDeclarations() const { return m_allowsLexicalDeclarations; }
DeclarationResultMask declareParameter(const Identifier* ident)
{
ASSERT(m_allowsVarDeclarations);
DeclarationResultMask result = DeclarationResult::Valid;
bool isArgumentsIdent = isArguments(m_vm, ident);
auto addResult = m_declaredVariables.add(ident->impl());
bool isValidStrictMode = (addResult.isNewEntry || !addResult.iterator->value.isParameter())
&& m_vm.propertyNames->eval != *ident && !isArgumentsIdent;
addResult.iterator->value.clearIsVar();
addResult.iterator->value.setIsParameter();
m_isValidStrictMode = m_isValidStrictMode && isValidStrictMode;
m_declaredParameters.add(ident->impl());
if (!isValidStrictMode)
result |= DeclarationResult::InvalidStrictMode;
if (isArgumentsIdent)
m_shadowsArguments = true;
if (!addResult.isNewEntry)
result |= DeclarationResult::InvalidDuplicateDeclaration;
return result;
}
bool usedVariablesContains(UniquedStringImpl* impl) const
{
for (const UniquedStringImplPtrSet& set : m_usedVariables) {
if (set.contains(impl))
return true;
}
return false;
}
template <typename Func>
void forEachUsedVariable(const Func& func)
{
for (const UniquedStringImplPtrSet& set : m_usedVariables) {
for (UniquedStringImpl* impl : set) {
if (func(impl) == IterationStatus::Done)
return;
}
}
}
void useVariable(const Identifier* ident, bool isEval)
{
useVariable(ident->impl(), isEval);
}
void useVariable(UniquedStringImpl* impl, bool isEval)
{
m_usesEval |= isEval;
m_usedVariables.last().add(impl);
}
void usePrivateName(const Identifier& ident)
{
ASSERT(m_allowsLexicalDeclarations);
useVariable(&ident, false);
}
void pushUsedVariableSet() { m_usedVariables.append(UniquedStringImplPtrSet()); }
size_t currentUsedVariablesSize() { return m_usedVariables.size(); }
void revertToPreviousUsedVariables(size_t size) { m_usedVariables.resize(size); }
void setNeedsFullActivation() { m_needsFullActivation = true; }
bool needsFullActivation() const { return m_needsFullActivation; }
bool isArrowFunctionBoundary() { return m_isArrowFunctionBoundary; }
bool isArrowFunction() { return m_isArrowFunction; }
bool hasDirectSuper() const { return m_hasDirectSuper; }
void setHasDirectSuper() { m_hasDirectSuper = true; }
bool needsSuperBinding() const { return m_needsSuperBinding; }
void setNeedsSuperBinding() { m_needsSuperBinding = true; }
void setEvalContextType(EvalContextType evalContextType) { m_evalContextType = evalContextType; }
EvalContextType evalContextType() { return m_evalContextType; }
InnerArrowFunctionCodeFeatures innerArrowFunctionFeatures() { return m_innerArrowFunctionFeatures; }
void setExpectedSuperBinding(SuperBinding superBinding) { m_expectedSuperBinding = static_cast<unsigned>(superBinding); }
SuperBinding expectedSuperBinding() const { return static_cast<SuperBinding>(m_expectedSuperBinding); }
void setConstructorKind(ConstructorKind constructorKind) { m_constructorKind = static_cast<unsigned>(constructorKind); }
ConstructorKind constructorKind() const { return static_cast<ConstructorKind>(m_constructorKind); }
void setInnerArrowFunctionUsesSuperCall() { m_innerArrowFunctionFeatures |= SuperCallInnerArrowFunctionFeature; }
void setInnerArrowFunctionUsesSuperProperty() { m_innerArrowFunctionFeatures |= SuperPropertyInnerArrowFunctionFeature; }
void setInnerArrowFunctionUsesEval() { m_innerArrowFunctionFeatures |= EvalInnerArrowFunctionFeature; }
void setInnerArrowFunctionUsesThis() { m_innerArrowFunctionFeatures |= ThisInnerArrowFunctionFeature; }
void setInnerArrowFunctionUsesNewTarget() { m_innerArrowFunctionFeatures |= NewTargetInnerArrowFunctionFeature; }
void setInnerArrowFunctionUsesArguments() { m_innerArrowFunctionFeatures |= ArgumentsInnerArrowFunctionFeature; }
bool isEvalContext() const { return m_isEvalContext; }
void setIsEvalContext(bool isEvalContext) { m_isEvalContext = isEvalContext; }
void setInnerArrowFunctionUsesEvalAndUseArgumentsIfNeeded()
{
ASSERT(m_isArrowFunction);
if (m_usesEval)
setInnerArrowFunctionUsesEval();
if (usedVariablesContains(m_vm.propertyNames->arguments.impl()))
setInnerArrowFunctionUsesArguments();
}
void addClosedVariableCandidateUnconditionally(UniquedStringImpl* impl)
{
m_closedVariableCandidates.add(impl);
}
void markLastUsedVariablesSetAsCaptured(unsigned from)
{
for (unsigned index = from; index < m_usedVariables.size(); ++index) {
for (UniquedStringImpl* impl : m_usedVariables[index])
m_closedVariableCandidates.add(impl);
}
}
void collectFreeVariables(Scope* nestedScope, bool shouldTrackClosedVariables)
{
if (nestedScope->m_usesEval)
m_usesEval = true;
{
UniquedStringImplPtrSet& destinationSet = m_usedVariables.last();
for (const UniquedStringImplPtrSet& usedVariablesSet : nestedScope->m_usedVariables) {
for (UniquedStringImpl* impl : usedVariablesSet) {
if (nestedScope->m_declaredVariables.contains(impl) || nestedScope->m_lexicalVariables.contains(impl))
continue;
// "arguments" reference should be resolved at function boudary.
if (nestedScope->isFunctionBoundary() && nestedScope->hasArguments() && impl == m_vm.propertyNames->arguments.impl() && !nestedScope->isArrowFunctionBoundary())
continue;
destinationSet.add(impl);
// We don't want a declared variable that is used in an inner scope to be thought of as captured if
// that inner scope is both a lexical scope and not a function. Only inner functions and "catch"
// statements can cause variables to be captured.
if (shouldTrackClosedVariables && (nestedScope->m_isFunctionBoundary || !nestedScope->m_isLexicalScope))
m_closedVariableCandidates.add(impl);
}
}
}
// Propagate closed variable candidates downwards within the same function.
// Cross function captures will be realized via m_usedVariables propagation.
if (shouldTrackClosedVariables && !nestedScope->m_isFunctionBoundary && nestedScope->m_closedVariableCandidates.size()) {
auto end = nestedScope->m_closedVariableCandidates.end();
auto begin = nestedScope->m_closedVariableCandidates.begin();
m_closedVariableCandidates.add(begin, end);
}
}
void mergeInnerArrowFunctionFeatures(InnerArrowFunctionCodeFeatures arrowFunctionCodeFeatures)
{
m_innerArrowFunctionFeatures = m_innerArrowFunctionFeatures | arrowFunctionCodeFeatures;
}
void getSloppyModeHoistedFunctions(UniquedStringImplPtrSet& sloppyModeHoistedFunctions)
{
for (UniquedStringImpl* function : m_sloppyModeHoistableFunctionCandidates) {
// ES6 Annex B.3.3. The only time we can't hoist a function is if a syntax error would
// be caused by declaring a var with that function's name or if we have a parameter with
// that function's name. Note that we would only cause a syntax error if we had a let/const/class
// variable with the same name.
if (!m_lexicalVariables.contains(function)) {
auto iter = m_declaredVariables.find(function);
bool isParameter = iter != m_declaredVariables.end() && iter->value.isParameter();
if (!isParameter) {
auto addResult = m_declaredVariables.add(function);
addResult.iterator->value.setIsVar();
addResult.iterator->value.setIsSloppyModeHoistingCandidate();
sloppyModeHoistedFunctions.add(function);
}
}
}
}
void getCapturedVars(IdentifierSet& capturedVariables)
{
if (m_needsFullActivation || m_usesEval) {
for (auto& entry : m_declaredVariables)
capturedVariables.add(entry.key);
return;
}
for (UniquedStringImpl* impl : m_closedVariableCandidates) {
// We refer to m_declaredVariables here directly instead of a hasDeclaredVariable because we want to mark the callee as captured.
if (!m_declaredVariables.contains(impl))
continue;
capturedVariables.add(impl);
}
}
LexicalScopeFeatures lexicalScopeFeatures() const { return m_lexicalScopeFeatures; }
void setStrictMode() { m_lexicalScopeFeatures |= StrictModeLexicalFeature; }
bool strictMode() const { return m_lexicalScopeFeatures & StrictModeLexicalFeature; }
bool isValidStrictMode() const { return m_isValidStrictMode; }
bool shadowsArguments() const { return m_shadowsArguments; }
void setHasNonSimpleParameterList()
{
m_isValidStrictMode = false;
m_hasNonSimpleParameterList = true;
}
bool hasNonSimpleParameterList() const { return m_hasNonSimpleParameterList; }
void copyCapturedVariablesToVector(const UniquedStringImplPtrSet& usedVariables, Vector<UniquedStringImpl*, 8>& vector)
{
for (UniquedStringImpl* impl : usedVariables) {
if (m_declaredVariables.contains(impl) || m_lexicalVariables.contains(impl))
continue;
vector.append(impl);
}
}
void fillParametersForSourceProviderCache(SourceProviderCacheItemCreationParameters& parameters, const UniquedStringImplPtrSet& capturesFromParameterExpressions)
{
ASSERT(m_isFunction);
parameters.usesEval = m_usesEval;
parameters.lexicalScopeFeatures = m_lexicalScopeFeatures;
parameters.needsFullActivation = m_needsFullActivation;
parameters.innerArrowFunctionFeatures = m_innerArrowFunctionFeatures;
parameters.needsSuperBinding = m_needsSuperBinding;
for (const UniquedStringImplPtrSet& set : m_usedVariables)
copyCapturedVariablesToVector(set, parameters.usedVariables);
// FIXME: https://bugs.webkit.org/show_bug.cgi?id=156962
// We add these unconditionally because we currently don't keep a separate
// declaration scope for a function's parameters and its var/let/const declarations.
// This is somewhat unfortunate and we should refactor to do this at some point
// because parameters logically form a parent scope to var/let/const variables.
// But because we don't do this, we must grab capture candidates from a parameter
// list before we parse the body of a function because the body's declarations
// might make us believe something isn't actually a capture candidate when it really
// is.
for (UniquedStringImpl* impl : capturesFromParameterExpressions)
parameters.usedVariables.append(impl);
}
void restoreFromSourceProviderCache(const SourceProviderCacheItem* info)
{
ASSERT(m_isFunction);
m_usesEval = info->usesEval;
m_lexicalScopeFeatures = info->lexicalScopeFeatures();
m_innerArrowFunctionFeatures = info->innerArrowFunctionFeatures;
m_needsFullActivation = info->needsFullActivation;
m_needsSuperBinding = info->needsSuperBinding;
UniquedStringImplPtrSet& destSet = m_usedVariables.last();
for (unsigned i = 0; i < info->usedVariablesCount; ++i)
destSet.add(info->usedVariables()[i].get());
}
class MaybeParseAsGeneratorForScope;
private:
void setIsFunction()
{
m_isFunction = true;
m_isFunctionBoundary = true;
m_hasArguments = true;
setIsLexicalScope();
m_isGenerator = false;
m_isGeneratorBoundary = false;
m_isArrowFunctionBoundary = false;
m_isArrowFunction = false;
m_isAsyncFunction = false;
m_isAsyncFunctionBoundary = false;
}
void setIsGeneratorFunction()
{
setIsFunction();
m_isGenerator = true;
}
void setIsGenerator()
{
setIsFunction();
m_isGenerator = true;
m_isGeneratorBoundary = true;
m_hasArguments = false;
}
void setIsArrowFunction()
{
setIsFunction();
m_isArrowFunctionBoundary = true;
m_isArrowFunction = true;
}
void setIsAsyncArrowFunction()
{
setIsArrowFunction();
m_isAsyncFunction = true;
}
void setIsAsyncFunction()
{
setIsFunction();
m_isAsyncFunction = true;
}
void setIsAsyncGeneratorFunction()
{
setIsFunction();
m_isAsyncFunction = true;
m_isGenerator = true;
}
void setIsAsyncGeneratorFunctionBody()
{
setIsFunction();
m_hasArguments = false;
m_isGenerator = true;
m_isGeneratorBoundary = true;
m_isAsyncFunction = true;
m_isAsyncFunctionBoundary = true;
}
void setIsAsyncFunctionBody()
{
setIsFunction();
m_hasArguments = false;
m_isAsyncFunction = true;
m_isAsyncFunctionBoundary = true;
}
void setIsAsyncArrowFunctionBody()
{
setIsArrowFunction();
m_hasArguments = false;
m_isAsyncFunction = true;
m_isAsyncFunctionBoundary = true;
}
const VM& m_vm;
bool m_shadowsArguments;
bool m_usesEval;
bool m_needsFullActivation;
bool m_hasDirectSuper;
bool m_needsSuperBinding;
bool m_allowsVarDeclarations;
bool m_allowsLexicalDeclarations;
LexicalScopeFeatures m_lexicalScopeFeatures;
bool m_isFunction;
bool m_isGenerator;
bool m_isGeneratorBoundary;
bool m_isArrowFunction;
bool m_isArrowFunctionBoundary;
bool m_isAsyncFunction;
bool m_isAsyncFunctionBoundary;
bool m_isLexicalScope;
bool m_isGlobalCodeScope;
bool m_isSimpleCatchParameterScope;
bool m_isCatchBlockScope;
bool m_isFunctionBoundary;
bool m_isValidStrictMode;
bool m_hasArguments;
bool m_isEvalContext;
bool m_hasNonSimpleParameterList;
bool m_isClassScope;
EvalContextType m_evalContextType;
unsigned m_constructorKind;
unsigned m_expectedSuperBinding;
int m_loopDepth;
int m_switchDepth;
InnerArrowFunctionCodeFeatures m_innerArrowFunctionFeatures;
typedef Vector<ScopeLabelInfo, 2> LabelStack;
std::unique_ptr<LabelStack> m_labels;
UniquedStringImplPtrSet m_declaredParameters;
VariableEnvironment m_declaredVariables;
VariableEnvironment m_lexicalVariables;
Vector<UniquedStringImplPtrSet, 6> m_usedVariables;
UniquedStringImplPtrSet m_variablesBeingHoisted;
UniquedStringImplPtrSet m_sloppyModeHoistableFunctionCandidates;
HashSet<UniquedStringImpl*> m_closedVariableCandidates;
DeclarationStacks::FunctionStack m_functionDeclarations;
};
typedef Vector<Scope, 10> ScopeStack;
struct ScopeRef {
ScopeRef(ScopeStack* scopeStack, unsigned index)
: m_scopeStack(scopeStack)
, m_index(index)
{
}
Scope* operator->() { return &m_scopeStack->at(m_index); }
unsigned index() const { return m_index; }
bool hasContainingScope()
{
return m_index && !m_scopeStack->at(m_index).isFunctionBoundary();
}
ScopeRef containingScope()
{
ASSERT(hasContainingScope());
return ScopeRef(m_scopeStack, m_index - 1);
}
bool operator==(const ScopeRef& other) const
{
ASSERT(other.m_scopeStack == m_scopeStack);
return m_index == other.m_index;
}
bool operator!=(const ScopeRef& other) const
{
return !(*this == other);
}
private:
ScopeStack* m_scopeStack;
unsigned m_index;
};
enum class ArgumentType { Normal, Spread };
enum class ParsingContext { Program, FunctionConstructor, Eval };
template <typename LexerType>
class Parser {
WTF_MAKE_NONCOPYABLE(Parser);
WTF_MAKE_FAST_ALLOCATED;
public:
Parser(VM&, const SourceCode&, JSParserBuiltinMode, JSParserStrictMode, JSParserScriptMode, SourceParseMode, SuperBinding, ConstructorKind defaultConstructorKindForTopLevelFunction = ConstructorKind::None, DerivedContextType = DerivedContextType::None, bool isEvalContext = false, EvalContextType = EvalContextType::None, DebuggerParseData* = nullptr, bool isInsideOrdinaryFunction = false);
~Parser();
template <class ParsedNode>
std::unique_ptr<ParsedNode> parse(ParserError&, const Identifier&, ParsingContext, std::optional<int> functionConstructorParametersEndPosition = std::nullopt, const PrivateNameEnvironment* = nullptr, const FixedVector<JSTextPosition>* = nullptr);
JSTextPosition positionBeforeLastNewline() const { return m_lexer->positionBeforeLastNewline(); }
JSTokenLocation locationBeforeLastToken() const { return m_lexer->lastTokenLocation(); }
struct CallOrApplyDepthScope {
CallOrApplyDepthScope(Parser* parser)
: m_parser(parser)
, m_parent(parser->m_callOrApplyDepthScope)
, m_depth(m_parent ? m_parent->m_depth + 1 : 0)
, m_depthOfInnermostChild(m_depth)
{
parser->m_callOrApplyDepthScope = this;
}
size_t distanceToInnermostChild() const
{
ASSERT(m_depthOfInnermostChild >= m_depth);
return m_depthOfInnermostChild - m_depth;
}
~CallOrApplyDepthScope()
{
if (m_parent)
m_parent->m_depthOfInnermostChild = std::max(m_depthOfInnermostChild, m_parent->m_depthOfInnermostChild);
m_parser->m_callOrApplyDepthScope = m_parent;
}
private:
Parser* m_parser;
CallOrApplyDepthScope* m_parent;
size_t m_depth;
size_t m_depthOfInnermostChild;
};
private:
struct AllowInOverride {
AllowInOverride(Parser* parser)
: m_parser(parser)
, m_oldAllowsIn(parser->m_allowsIn)
{
parser->m_allowsIn = true;
}
~AllowInOverride()
{
m_parser->m_allowsIn = m_oldAllowsIn;
}
Parser* m_parser;
bool m_oldAllowsIn;
};
struct AutoPopScopeRef : public ScopeRef {
AutoPopScopeRef(Parser* parser, ScopeRef scope)
: ScopeRef(scope)
, m_parser(parser)
{
}
~AutoPopScopeRef()
{
if (m_parser)
m_parser->popScope(*this, false);
}
void setPopped()
{
m_parser = nullptr;
}
private:
Parser* m_parser;
};
struct AutoCleanupLexicalScope {
// We can allocate this object on the stack without actually knowing beforehand if we're
// going to create a new lexical scope. If we decide to create a new lexical scope, we
// can pass the scope into this obejct and it will take care of the cleanup for us if the parse fails.
// This is helpful if we may fail from syntax errors after creating a lexical scope conditionally.
AutoCleanupLexicalScope()
: m_scope(nullptr, UINT_MAX)
, m_parser(nullptr)
{
}
~AutoCleanupLexicalScope()
{
// This should only ever be called if we fail from a syntax error. Otherwise
// it's the intention that a user of this class pops this scope manually on a
// successful parse.
if (isValid())
m_parser->popScope(*this, false);
}
void setIsValid(ScopeRef& scope, Parser* parser)
{
RELEASE_ASSERT(scope->isLexicalScope());
m_scope = scope;
m_parser = parser;
}
bool isValid() const { return !!m_parser; }
void setPopped()
{
m_parser = nullptr;
}
ScopeRef& scope() { return m_scope; }
private:
ScopeRef m_scope;
Parser* m_parser;
};
enum ExpressionErrorClass {
ErrorIndicatesNothing = 0,
ErrorIndicatesPattern,
ErrorIndicatesAsyncArrowFunction
};
struct ExpressionErrorClassifier {
ExpressionErrorClassifier(Parser* parser)
: m_class(ErrorIndicatesNothing)
, m_previous(parser->m_expressionErrorClassifier)
, m_parser(parser)
{
m_parser->m_expressionErrorClassifier = this;
}
~ExpressionErrorClassifier()
{
m_parser->m_expressionErrorClassifier = m_previous;
}
void classifyExpressionError(ExpressionErrorClass classification)
{
if (m_class != ErrorIndicatesNothing)
return;
m_class = classification;
}
void forceClassifyExpressionError(ExpressionErrorClass classification)
{
m_class = classification;
}
void reclassifyExpressionError(ExpressionErrorClass oldClassification, ExpressionErrorClass classification)
{
if (m_class != oldClassification)
return;
m_class = classification;
}
void propagateExpressionErrorClass()
{
if (m_previous)
m_previous->m_class = m_class;
}
bool indicatesPossiblePattern() const { return m_class == ErrorIndicatesPattern; }
bool indicatesPossibleAsyncArrowFunction() const { return m_class == ErrorIndicatesAsyncArrowFunction; }
private:
ExpressionErrorClass m_class;
ExpressionErrorClassifier* m_previous;
Parser* m_parser;
};
ALWAYS_INLINE void classifyExpressionError(ExpressionErrorClass classification)
{
if (m_expressionErrorClassifier)
m_expressionErrorClassifier->classifyExpressionError(classification);
}
ALWAYS_INLINE void forceClassifyExpressionError(ExpressionErrorClass classification)
{
if (m_expressionErrorClassifier)
m_expressionErrorClassifier->forceClassifyExpressionError(classification);
}
ALWAYS_INLINE void reclassifyExpressionError(ExpressionErrorClass oldClassification, ExpressionErrorClass classification)
{
if (m_expressionErrorClassifier)
m_expressionErrorClassifier->reclassifyExpressionError(oldClassification, classification);
}
ALWAYS_INLINE DestructuringKind destructuringKindFromDeclarationType(DeclarationType type)
{
switch (type) {
case DeclarationType::VarDeclaration:
return DestructuringKind::DestructureToVariables;
case DeclarationType::LetDeclaration:
return DestructuringKind::DestructureToLet;
case DeclarationType::ConstDeclaration:
return DestructuringKind::DestructureToConst;
}
RELEASE_ASSERT_NOT_REACHED();
return DestructuringKind::DestructureToVariables;
}
ALWAYS_INLINE const char* declarationTypeToVariableKind(DeclarationType type)
{
switch (type) {
case DeclarationType::VarDeclaration:
return "variable name";
case DeclarationType::LetDeclaration:
case DeclarationType::ConstDeclaration:
return "lexical variable name";
}
RELEASE_ASSERT_NOT_REACHED();
return "invalid";
}
ALWAYS_INLINE AssignmentContext assignmentContextFromDeclarationType(DeclarationType type)
{
switch (type) {
case DeclarationType::ConstDeclaration:
return AssignmentContext::ConstDeclarationStatement;
default:
return AssignmentContext::DeclarationStatement;
}
}
ALWAYS_INLINE SourceParseMode sourceParseMode() const { return m_parseMode; }
ALWAYS_INLINE bool isEvalOrArguments(const Identifier* ident) { return isEvalOrArgumentsIdentifier(m_vm, ident); }
ScopeRef upperScope(int n)
{
ASSERT(m_scopeStack.size() >= size_t(1 + n));
return ScopeRef(&m_scopeStack, m_scopeStack.size() - 1 - n);
}
ScopeRef currentScope()
{
return ScopeRef(&m_scopeStack, m_scopeStack.size() - 1);
}
ScopeRef currentVariableScope()
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (!m_scopeStack[i].allowsVarDeclarations()) {
i--;
ASSERT(i < m_scopeStack.size());
}
return ScopeRef(&m_scopeStack, i);
}
ScopeRef currentLexicalDeclarationScope()
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (!m_scopeStack[i].allowsLexicalDeclarations()) {
i--;
ASSERT(i < m_scopeStack.size());
}
return ScopeRef(&m_scopeStack, i);
}
ScopeRef currentFunctionScope()
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (i && !m_scopeStack[i].isFunctionBoundary()) {
i--;
ASSERT(i < m_scopeStack.size());
}
// When reaching the top level scope (it can be non function scope), we return it.
return ScopeRef(&m_scopeStack, i);
}
std::optional<ScopeRef> findPrivateNameScope()
{
ASSERT(m_scopeStack.size());
unsigned i = m_scopeStack.size() - 1;
while (i && !m_scopeStack[i].isPrivateNameScope())
i--;
if (m_scopeStack[i].isPrivateNameScope())
return ScopeRef(&m_scopeStack, i);
return std::nullopt;
}
ScopeRef closestParentOrdinaryFunctionNonLexicalScope()
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size() && m_scopeStack.size());
while (i && (!m_scopeStack[i].isFunctionBoundary() || m_scopeStack[i].isGeneratorBoundary() || m_scopeStack[i].isAsyncFunctionBoundary() || m_scopeStack[i].isArrowFunctionBoundary()))
i--;
// When reaching the top level scope (it can be non ordinary function scope), we return it.
return ScopeRef(&m_scopeStack, i);
}
ScopeRef closestClassScopeOrTopLevelScope()
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (i && !m_scopeStack[i].isClassScope())
i--;
return ScopeRef(&m_scopeStack, i);
}
ScopeRef pushScope()
{
LexicalScopeFeatures lexicalScopeFeatures = NoLexicalFeatures;
bool isFunction = false;
bool isGenerator = false;
bool isArrowFunction = false;
bool isAsyncFunction = false;
if (!m_scopeStack.isEmpty()) {
lexicalScopeFeatures = m_scopeStack.last().lexicalScopeFeatures();
isFunction = m_scopeStack.last().isFunction();
isGenerator = m_scopeStack.last().isGenerator();
isArrowFunction = m_scopeStack.last().isArrowFunction();
isAsyncFunction = m_scopeStack.last().isAsyncFunction();
}
m_scopeStack.constructAndAppend(m_vm, lexicalScopeFeatures, isFunction, isGenerator, isArrowFunction, isAsyncFunction);
return currentScope();
}
std::tuple<VariableEnvironment, DeclarationStacks::FunctionStack> popScopeInternal(ScopeRef& scope, bool shouldTrackClosedVariables)
{
EXCEPTION_ASSERT_UNUSED(scope, scope.index() == m_scopeStack.size() - 1);
ASSERT(m_scopeStack.size() > 1);
Scope& lastScope = m_scopeStack.last();
// Finalize lexical variables.
lastScope.finalizeLexicalEnvironment();
m_scopeStack[m_scopeStack.size() - 2].collectFreeVariables(&lastScope, shouldTrackClosedVariables);
if (lastScope.isArrowFunction())
lastScope.setInnerArrowFunctionUsesEvalAndUseArgumentsIfNeeded();
if (!(lastScope.isFunctionBoundary() && !lastScope.isArrowFunctionBoundary()))
m_scopeStack[m_scopeStack.size() - 2].mergeInnerArrowFunctionFeatures(lastScope.innerArrowFunctionFeatures());
if (!lastScope.isFunctionBoundary() && lastScope.needsFullActivation())
m_scopeStack[m_scopeStack.size() - 2].setNeedsFullActivation();
std::tuple result { lastScope.takeLexicalEnvironment(), lastScope.takeFunctionDeclarations() };
m_scopeStack.removeLast();
return result;
}
ALWAYS_INLINE std::tuple<VariableEnvironment, DeclarationStacks::FunctionStack> popScope(ScopeRef& scope, bool shouldTrackClosedVariables)
{
return popScopeInternal(scope, shouldTrackClosedVariables);
}
ALWAYS_INLINE std::tuple<VariableEnvironment, DeclarationStacks::FunctionStack> popScope(AutoPopScopeRef& scope, bool shouldTrackClosedVariables)
{
scope.setPopped();
return popScopeInternal(scope, shouldTrackClosedVariables);
}
ALWAYS_INLINE std::tuple<VariableEnvironment, DeclarationStacks::FunctionStack> popScope(AutoCleanupLexicalScope& cleanupScope, bool shouldTrackClosedVariables)
{
RELEASE_ASSERT(cleanupScope.isValid());
ScopeRef& scope = cleanupScope.scope();
cleanupScope.setPopped();
return popScopeInternal(scope, shouldTrackClosedVariables);
}
NEVER_INLINE DeclarationResultMask declareHoistedVariable(const Identifier* ident)
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (true) {
// Annex B.3.5 exempts `try {} catch (e) { var e; }` from being a syntax error.
if (m_scopeStack[i].hasLexicallyDeclaredVariable(*ident) && !m_scopeStack[i].isSimpleCatchParameterScope())
return DeclarationResult::InvalidDuplicateDeclaration;
if (m_scopeStack[i].allowsVarDeclarations())
return m_scopeStack[i].declareVariable(ident);
m_scopeStack[i].addVariableBeingHoisted(ident);
i--;
ASSERT(i < m_scopeStack.size());
}
}
DeclarationResultMask declareVariable(const Identifier* ident, DeclarationType type = DeclarationType::VarDeclaration, DeclarationImportType importType = DeclarationImportType::NotImported)
{
if (type == DeclarationType::VarDeclaration)
return declareHoistedVariable(ident);
ASSERT(type == DeclarationType::LetDeclaration || type == DeclarationType::ConstDeclaration);
// Lexical variables declared at a top level scope that shadow arguments or vars are not allowed.
if (!m_lexer->isReparsingFunction() && m_statementDepth == 1 && (hasDeclaredParameter(*ident) || hasDeclaredVariable(*ident)))
return DeclarationResult::InvalidDuplicateDeclaration;
ScopeRef scope = currentLexicalDeclarationScope();
if (scope->isCatchBlockScope() && scope.containingScope()->hasLexicallyDeclaredVariable(*ident))
return DeclarationResult::InvalidDuplicateDeclaration;
return scope->declareLexicalVariable(ident, type == DeclarationType::ConstDeclaration, importType);
}
std::pair<DeclarationResultMask, ScopeRef> declareFunction(const Identifier* ident)
{
if ((m_statementDepth == 1) || (!strictMode() && !currentScope()->isFunction() && !closestParentOrdinaryFunctionNonLexicalScope()->isEvalContext())) {
// Functions declared at the top-most scope (both in sloppy and strict mode) are declared as vars
// for backwards compatibility. This allows us to declare functions with the same name more than once.
// In sloppy mode, we always declare functions as vars.
bool declareAsVar = true;
bool isSloppyModeHoistingCandidate = false;
ScopeRef variableScope = currentVariableScope();
return std::make_pair(variableScope->declareFunction(ident, declareAsVar, isSloppyModeHoistingCandidate), variableScope);
}
bool declareAsVar = false;
ScopeRef lexicalVariableScope = currentLexicalDeclarationScope();
if (lexicalVariableScope->isCatchBlockScope() && lexicalVariableScope.containingScope()->hasLexicallyDeclaredVariable(*ident))
return std::make_pair(DeclarationResult::InvalidDuplicateDeclaration, lexicalVariableScope);
if (!strictMode()) {
ASSERT(currentScope()->isFunction() || closestParentOrdinaryFunctionNonLexicalScope()->isEvalContext());
// Functions declared inside a function inside a nested block scope in sloppy mode are subject to this
// crazy rule defined inside Annex B.3.3 in the ES6 spec. It basically states that we will create
// the function as a local block scoped variable, but when we evaluate the block that the function is
// contained in, we will assign the function to a "var" variable only if declaring such a "var" wouldn't
// be a syntax error and if there isn't a parameter with the same name. (It would only be a syntax error if
// there are is a let/class/const with the same name). Note that this mean we only do the "var" hoisting
// binding if the block evaluates. For example, this means we wont won't perform the binding if it's inside
// the untaken branch of an if statement.
bool isSloppyModeHoistingCandidate = true;
ScopeRef varScope = currentVariableScope();
varScope->addSloppyModeHoistableFunctionCandidate(ident);
ASSERT(varScope != lexicalVariableScope);
return std::make_pair(lexicalVariableScope->declareFunction(ident, declareAsVar, isSloppyModeHoistingCandidate), lexicalVariableScope);
}
bool isSloppyModeHoistingCandidate = false;
return std::make_pair(lexicalVariableScope->declareFunction(ident, declareAsVar, isSloppyModeHoistingCandidate), lexicalVariableScope);
}
NEVER_INLINE bool hasDeclaredVariable(const Identifier& ident)
{
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (!m_scopeStack[i].allowsVarDeclarations()) {
i--;
ASSERT(i < m_scopeStack.size());
}
return m_scopeStack[i].hasDeclaredVariable(ident);
}
NEVER_INLINE bool hasDeclaredParameter(const Identifier& ident)
{
// FIXME: hasDeclaredParameter() is not valid during reparsing of generator or async function bodies, because their formal
// parameters are declared in a scope unavailable during reparsing. Note that it is redundant to call this function during
// reparsing anyways, as the function is already guaranteed to be valid by the original parsing.
// https://bugs.webkit.org/show_bug.cgi?id=164087
ASSERT(!m_lexer->isReparsingFunction());
unsigned i = m_scopeStack.size() - 1;
ASSERT(i < m_scopeStack.size());
while (!m_scopeStack[i].allowsVarDeclarations()) {
i--;
ASSERT(i < m_scopeStack.size());
}
if (m_scopeStack[i].isGeneratorBoundary() || m_scopeStack[i].isAsyncFunctionBoundary()) {
// The formal parameters which need to be verified for Generators and Async Function bodies occur
// in the outer wrapper function, so pick the outer scope here.
i--;
ASSERT(i < m_scopeStack.size());
}
return m_scopeStack[i].hasDeclaredParameter(ident);
}
bool exportName(const Identifier& ident)
{
ASSERT(currentScope().index() == 0);
ASSERT(m_moduleScopeData);
return m_moduleScopeData->exportName(ident);
}
ScopeStack m_scopeStack;
const SourceProviderCacheItem* findCachedFunctionInfo(int openBracePos)
{
return m_functionCache ? m_functionCache->get(openBracePos) : nullptr;
}
Parser();
struct ParseInnerResult {
FunctionParameters* parameters;
SourceElements* sourceElements;
DeclarationStacks::FunctionStack functionDeclarations;
VariableEnvironment varDeclarations;
VariableEnvironment lexicalVariables;
UniquedStringImplPtrSet sloppyModeHoistedFunctions;
CodeFeatures features;
int numConstants;
};
Expected<ParseInnerResult, String> parseInner(const Identifier&, ParsingContext, std::optional<int> functionConstructorParametersEndPosition, const FixedVector<JSTextPosition>*, const PrivateNameEnvironment* parentScopePrivateNames);
// Used to determine type of error to report.
bool isFunctionMetadataNode(ScopeNode*) { return false; }
bool isFunctionMetadataNode(FunctionMetadataNode*) { return true; }
ALWAYS_INLINE void next(OptionSet<LexerFlags> lexerFlags = { })
{
int lastLine = m_token.m_location.line;
int lastTokenEnd = m_token.m_location.endOffset;
int lastTokenLineStart = m_token.m_location.lineStartOffset;
m_lastTokenEndPosition = JSTextPosition(lastLine, lastTokenEnd, lastTokenLineStart);
m_lexer->setLastLineNumber(lastLine);
m_token.m_type = m_lexer->lex(&m_token, lexerFlags, strictMode());
}
ALWAYS_INLINE void nextWithoutClearingLineTerminator(OptionSet<LexerFlags> lexerFlags = { })
{
int lastLine = m_token.m_location.line;
int lastTokenEnd = m_token.m_location.endOffset;
int lastTokenLineStart = m_token.m_location.lineStartOffset;
m_lastTokenEndPosition = JSTextPosition(lastLine, lastTokenEnd, lastTokenLineStart);
m_lexer->setLastLineNumber(lastLine);
m_token.m_type = m_lexer->lexWithoutClearingLineTerminator(&m_token, lexerFlags, strictMode());
}
ALWAYS_INLINE void nextExpectIdentifier(OptionSet<LexerFlags> lexerFlags = { })
{
int lastLine = m_token.m_location.line;
int lastTokenEnd = m_token.m_location.endOffset;
int lastTokenLineStart = m_token.m_location.lineStartOffset;
m_lastTokenEndPosition = JSTextPosition(lastLine, lastTokenEnd, lastTokenLineStart);
m_lexer->setLastLineNumber(lastLine);
m_token.m_type = m_lexer->lexExpectIdentifier(&m_token, lexerFlags, strictMode());
}
template <class TreeBuilder>
ALWAYS_INLINE void lexCurrentTokenAgainUnderCurrentContext(TreeBuilder& context)
{
auto savePoint = createSavePoint(context);
restoreSavePoint(context, savePoint);
}
ALWAYS_INLINE bool nextTokenIsColon()
{
return m_lexer->nextTokenIsColon();
}
ALWAYS_INLINE bool consume(JSTokenType expected, OptionSet<LexerFlags> flags = { })
{
bool result = m_token.m_type == expected;
if (result)
next(flags);
return result;
}
void printUnexpectedTokenText(WTF::PrintStream&);
ALWAYS_INLINE StringView getToken()
{
return m_lexer->getToken(m_token);
}
ALWAYS_INLINE StringView getToken(const JSToken& token)
{
return m_lexer->getToken(token);
}
ALWAYS_INLINE bool match(JSTokenType expected)
{
return m_token.m_type == expected;
}
ALWAYS_INLINE bool matchAndUpdate(JSTokenType expected, const JSToken& token)
{
if (match(expected)) {
m_token = token;
return true;
}
return false;
}
ALWAYS_INLINE bool matchContextualKeyword(const Identifier& identifier)
{
return m_token.m_type == IDENT && *m_token.m_data.ident == identifier && !m_token.m_data.escaped;
}
ALWAYS_INLINE bool matchIdentifierOrKeyword()
{
return isIdentifierOrKeyword(m_token);
}
ALWAYS_INLINE unsigned tokenStart()
{
return m_token.m_location.startOffset;
}
ALWAYS_INLINE const JSTextPosition& tokenStartPosition()
{
return m_token.m_startPosition;
}
ALWAYS_INLINE int tokenLine()
{
return m_token.m_location.line;
}
ALWAYS_INLINE int tokenColumn()
{
return tokenStart() - tokenLineStart();
}
ALWAYS_INLINE const JSTextPosition& tokenEndPosition()
{
return m_token.m_endPosition;
}
ALWAYS_INLINE unsigned tokenLineStart()
{
return m_token.m_location.lineStartOffset;
}
ALWAYS_INLINE const JSTokenLocation& tokenLocation()
{
return m_token.m_location;
}
void setErrorMessage(const String& message)
{
ASSERT_WITH_MESSAGE(!message.isEmpty(), "Attempted to set the empty string as an error message. Likely caused by invalid UTF8 used when creating the message.");
m_errorMessage = message;
if (m_errorMessage.isEmpty())
m_errorMessage = "Unparseable script"_s;
}
NEVER_INLINE void logError(bool);
template <typename... Args>
NEVER_INLINE void logError(bool, Args&&...);
NEVER_INLINE void updateErrorWithNameAndMessage(const char* beforeMessage, const String& name, const char* afterMessage)
{
m_errorMessage = makeString(beforeMessage, " '", name, "' ", afterMessage);
}
NEVER_INLINE void updateErrorMessage(const char* msg)
{
ASSERT(msg);
m_errorMessage = String::fromLatin1(msg);
ASSERT(!m_errorMessage.isNull());
}
ALWAYS_INLINE void recordPauseLocation(const JSTextPosition&);
ALWAYS_INLINE void recordFunctionEntryLocation(const JSTextPosition&);
ALWAYS_INLINE void recordFunctionLeaveLocation(const JSTextPosition&);
void startLoop() { currentScope()->startLoop(); }
void endLoop() { currentScope()->endLoop(); }
void startSwitch() { currentScope()->startSwitch(); }
void endSwitch() { currentScope()->endSwitch(); }
LexicalScopeFeatures lexicalScopeFeatures() { return currentScope()->lexicalScopeFeatures(); }
void setStrictMode() { currentScope()->setStrictMode(); }
bool strictMode() { return currentScope()->strictMode(); }
bool isValidStrictMode()
{
int i = m_scopeStack.size() - 1;
if (!m_scopeStack[i].isValidStrictMode())
return false;
// In the case of Generator or Async function bodies, also check the wrapper function, whose name or
// arguments may be invalid.
if (UNLIKELY((m_scopeStack[i].isGeneratorBoundary() || m_scopeStack[i].isAsyncFunctionBoundary()) && i))
return m_scopeStack[i - 1].isValidStrictMode();
return true;
}
DeclarationResultMask declareParameter(const Identifier* ident) { return currentScope()->declareParameter(ident); }
bool declareRestOrNormalParameter(const Identifier&, const Identifier**);
bool breakIsValid()
{
ScopeRef current = currentScope();
while (!current->breakIsValid()) {
if (!current.hasContainingScope())
return false;
current = current.containingScope();
}
return true;
}
bool continueIsValid()
{
ScopeRef current = currentScope();
while (!current->continueIsValid()) {
if (!current.hasContainingScope())
return false;
current = current.containingScope();
}
return true;
}
void pushLabel(const Identifier* label, bool isLoop) { currentScope()->pushLabel(label, isLoop); }
void popLabel(ScopeRef scope) { scope->popLabel(); }
ScopeLabelInfo* getLabel(const Identifier* label)
{
ScopeRef current = currentScope();
ScopeLabelInfo* result = nullptr;
while (!(result = current->getLabel(label))) {
if (!current.hasContainingScope())
return nullptr;
current = current.containingScope();
}
return result;
}
ALWAYS_INLINE bool matchSpecIdentifier()
{
return match(IDENT) || isAllowedIdentifierLet(m_token) || isAllowedIdentifierYield(m_token) || isPossiblyEscapedAwait(m_token);
}
// Special case where some information is already known.
ALWAYS_INLINE bool matchSpecIdentifier(bool canUseYield, bool isAwait)
{
return isAwait || match(IDENT) || isAllowedIdentifierLet(m_token) || (canUseYield && isPossiblyEscapedYield(m_token));
}
ALWAYS_INLINE bool matchIdentifierOrPossiblyEscapedContextualKeyword()
{
return match(IDENT) || isPossiblyEscapedLet(m_token) || isPossiblyEscapedYield(m_token) || isPossiblyEscapedAwait(m_token);
}
template <class TreeBuilder> TreeSourceElements parseSourceElements(TreeBuilder&, SourceElementsMode);
template <class TreeBuilder> TreeSourceElements parseGeneratorFunctionSourceElements(TreeBuilder&, const Identifier& name, SourceElementsMode);
template <class TreeBuilder> TreeSourceElements parseAsyncFunctionSourceElements(TreeBuilder&, bool isArrowFunctionBodyExpression, SourceElementsMode);
template <class TreeBuilder> TreeSourceElements parseAsyncGeneratorFunctionSourceElements(TreeBuilder&, bool isArrowFunctionBodyExpression, SourceElementsMode);
template <class TreeBuilder> TreeSourceElements parseSingleFunction(TreeBuilder&, std::optional<int> functionConstructorParametersEndPosition);
template <class TreeBuilder> TreeSourceElements parseClassFieldInitializerSourceElements(TreeBuilder&, const FixedVector<JSTextPosition>&);
template <class TreeBuilder> TreeStatement parseStatementListItem(TreeBuilder&, const Identifier*& directive, unsigned* directiveLiteralLength);
template <class TreeBuilder> TreeStatement parseStatement(TreeBuilder&, const Identifier*& directive, unsigned* directiveLiteralLength = nullptr);
enum class ExportType { Exported, NotExported };
template <class TreeBuilder> TreeStatement parseClassDeclaration(TreeBuilder&, ExportType = ExportType::NotExported, DeclarationDefaultContext = DeclarationDefaultContext::Standard);
enum class FunctionDeclarationType { Declaration, Statement };
template <class TreeBuilder> TreeStatement parseFunctionDeclaration(TreeBuilder&, FunctionDeclarationType = FunctionDeclarationType::Declaration, ExportType = ExportType::NotExported, DeclarationDefaultContext = DeclarationDefaultContext::Standard, std::optional<int> functionConstructorParametersEndPosition = std::nullopt);
template <class TreeBuilder> TreeStatement parseFunctionDeclarationStatement(TreeBuilder&, bool parentAllowsFunctionDeclarationAsStatement);
template <class TreeBuilder> TreeStatement parseAsyncFunctionDeclaration(TreeBuilder&, ExportType = ExportType::NotExported, DeclarationDefaultContext = DeclarationDefaultContext::Standard, std::optional<int> functionConstructorParametersEndPosition = std::nullopt);
template <class TreeBuilder> TreeStatement parseVariableDeclaration(TreeBuilder&, DeclarationType, ExportType = ExportType::NotExported);
template <class TreeBuilder> TreeStatement parseDoWhileStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseWhileStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseForStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseBreakStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseContinueStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseReturnStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseThrowStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseWithStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseSwitchStatement(TreeBuilder&);
template <class TreeBuilder> TreeClauseList parseSwitchClauses(TreeBuilder&);
template <class TreeBuilder> TreeClause parseSwitchDefaultClause(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseTryStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseDebuggerStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseExpressionStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseExpressionOrLabelStatement(TreeBuilder&, bool allowFunctionDeclarationAsStatement);
template <class TreeBuilder> TreeStatement parseIfStatement(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseBlockStatement(TreeBuilder&, bool isCatchBlock = false);
enum class IsOnlyChildOfStatement { Yes, No };
template <class TreeBuilder> TreeExpression parseExpression(TreeBuilder&, IsOnlyChildOfStatement = IsOnlyChildOfStatement::No);
template <class TreeBuilder> TreeExpression parseAssignmentExpression(TreeBuilder&, ExpressionErrorClassifier&);
template <class TreeBuilder> TreeExpression parseAssignmentExpression(TreeBuilder&);
template <class TreeBuilder> TreeExpression parseAssignmentExpressionOrPropagateErrorClass(TreeBuilder&);
template <class TreeBuilder> TreeExpression parseYieldExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseConditionalExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseBinaryExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseUnaryExpression(TreeBuilder&);
template <class TreeBuilder> NEVER_INLINE TreeExpression parseAwaitExpression(TreeBuilder&);
template <class TreeBuilder> TreeExpression parseMemberExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parsePrimaryExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseArrayLiteral(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseObjectLiteral(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeClassExpression parseClassExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseFunctionExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseAsyncFunctionExpression(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeArguments parseArguments(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression parseArgument(TreeBuilder&, ArgumentType&);
template <class TreeBuilder> TreeProperty parseProperty(TreeBuilder&);
template <class TreeBuilder> TreeExpression parsePropertyMethod(TreeBuilder& context, const Identifier* methodName);
template <class TreeBuilder> TreeProperty parseGetterSetter(TreeBuilder&, PropertyNode::Type, unsigned getterOrSetterStartOffset, ConstructorKind, ClassElementTag);
template <class TreeBuilder> ALWAYS_INLINE TreeFunctionBody parseFunctionBody(TreeBuilder&, SyntaxChecker&, const JSTokenLocation&, int, int functionKeywordStart, int functionNameStart, int parametersStart, ConstructorKind, SuperBinding, FunctionBodyType, unsigned);
template <class TreeBuilder> ALWAYS_INLINE bool parseFormalParameters(TreeBuilder&, TreeFormalParameterList, bool isArrowFunction, bool isMethod, unsigned&);
enum VarDeclarationListContext { ForLoopContext, VarDeclarationContext };
template <class TreeBuilder> TreeExpression parseVariableDeclarationList(TreeBuilder&, int& declarations, TreeDestructuringPattern& lastPattern, TreeExpression& lastInitializer, JSTextPosition& identStart, JSTextPosition& initStart, JSTextPosition& initEnd, VarDeclarationListContext, DeclarationType, ExportType, bool& forLoopConstDoesNotHaveInitializer);
template <class TreeBuilder> TreeSourceElements parseArrowFunctionSingleExpressionBodySourceElements(TreeBuilder&);
template <class TreeBuilder> TreeExpression parseArrowFunctionExpression(TreeBuilder&, bool isAsync);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern createBindingPattern(TreeBuilder&, DestructuringKind, ExportType, const Identifier&, const JSToken&, AssignmentContext, const Identifier** duplicateIdentifier);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern createAssignmentElement(TreeBuilder&, TreeExpression&, const JSTextPosition&, const JSTextPosition&);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern parseObjectRestBindingOrAssignmentElement(TreeBuilder& context, DestructuringKind, ExportType, const Identifier** duplicateIdentifier, AssignmentContext bindingContext);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern parseBindingOrAssignmentElement(TreeBuilder& context, DestructuringKind, ExportType, const Identifier** duplicateIdentifier, bool* hasDestructuringPattern, AssignmentContext bindingContext, int depth);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern parseObjectRestAssignmentElement(TreeBuilder& context);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern parseAssignmentElement(TreeBuilder& context, DestructuringKind, ExportType, const Identifier** duplicateIdentifier, bool* hasDestructuringPattern, AssignmentContext bindingContext, int depth);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern parseObjectRestElement(TreeBuilder&, DestructuringKind, ExportType, const Identifier** duplicateIdentifier = nullptr, AssignmentContext = AssignmentContext::DeclarationStatement);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern parseDestructuringPattern(TreeBuilder&, DestructuringKind, ExportType, const Identifier** duplicateIdentifier = nullptr, bool* hasDestructuringPattern = nullptr, AssignmentContext = AssignmentContext::DeclarationStatement, int depth = 0);
template <class TreeBuilder> NEVER_INLINE TreeDestructuringPattern tryParseDestructuringPatternExpression(TreeBuilder&, AssignmentContext);
template <class TreeBuilder> NEVER_INLINE TreeExpression parseDefaultValueForDestructuringPattern(TreeBuilder&);
template <class TreeBuilder> TreeSourceElements parseModuleSourceElements(TreeBuilder&);
enum class ImportSpecifierType { NamespaceImport, NamedImport, DefaultImport };
template <class TreeBuilder> typename TreeBuilder::ImportSpecifier parseImportClauseItem(TreeBuilder&, ImportSpecifierType);
template <class TreeBuilder> typename TreeBuilder::ModuleName parseModuleName(TreeBuilder&);
template <class TreeBuilder> typename TreeBuilder::ImportAssertionList parseImportAssertions(TreeBuilder&);
template <class TreeBuilder> TreeStatement parseImportDeclaration(TreeBuilder&);
template <class TreeBuilder> typename TreeBuilder::ExportSpecifier parseExportSpecifier(TreeBuilder& context, Vector<std::pair<const Identifier*, const Identifier*>>& maybeExportedLocalNames, bool& hasKeywordForLocalBindings, bool& hasReferencedModuleExportNames);
template <class TreeBuilder> TreeStatement parseExportDeclaration(TreeBuilder&);
template <class TreeBuilder> ALWAYS_INLINE TreeExpression createResolveAndUseVariable(TreeBuilder&, const Identifier*, bool isEval, const JSTextPosition&, const JSTokenLocation&);
enum class FunctionDefinitionType { Expression, Declaration, Method };
template <class TreeBuilder> NEVER_INLINE bool parseFunctionInfo(TreeBuilder&, FunctionNameRequirements, bool nameIsInContainingScope, ConstructorKind, SuperBinding, int functionKeywordStart, ParserFunctionInfo<TreeBuilder>&, FunctionDefinitionType, std::optional<int> functionConstructorParametersEndPosition = std::nullopt);
template <class TreeBuilder> ALWAYS_INLINE bool isArrowFunctionParameters(TreeBuilder&);
template <class TreeBuilder, class FunctionInfoType> NEVER_INLINE typename TreeBuilder::FormalParameterList parseFunctionParameters(TreeBuilder&, FunctionInfoType&);
template <class TreeBuilder> NEVER_INLINE typename TreeBuilder::FormalParameterList createGeneratorParameters(TreeBuilder&, unsigned& parameterCount);
template <class TreeBuilder> NEVER_INLINE TreeClassExpression parseClass(TreeBuilder&, FunctionNameRequirements, ParserClassInfo<TreeBuilder>&);
template <class TreeBuilder> NEVER_INLINE typename TreeBuilder::TemplateString parseTemplateString(TreeBuilder& context, bool isTemplateHead, typename LexerType::RawStringsBuildMode, bool& elementIsTail);
template <class TreeBuilder> NEVER_INLINE typename TreeBuilder::TemplateLiteral parseTemplateLiteral(TreeBuilder&, typename LexerType::RawStringsBuildMode);
template <class TreeBuilder> NEVER_INLINE const char* metaPropertyName(TreeBuilder&, TreeExpression);
template <class TreeBuilder> ALWAYS_INLINE bool isSimpleAssignmentTarget(TreeBuilder&, TreeExpression);
ALWAYS_INLINE int isBinaryOperator(JSTokenType);
bool allowAutomaticSemicolon();
bool autoSemiColon()
{
if (m_token.m_type == SEMICOLON) {
next();
return true;
}
return allowAutomaticSemicolon();
}
bool canRecurse()
{
return m_vm.isSafeToRecurse();
}
const JSTextPosition& lastTokenEndPosition() const
{
return m_lastTokenEndPosition;
}
bool hasError() const
{
return !m_errorMessage.isNull();
}
bool isAllowedIdentifierLet(const JSToken& token)
{
return isPossiblyEscapedLet(token) && !strictMode();
}
ALWAYS_INLINE bool isPossiblyEscapedLet(const JSToken& token)
{
return token.m_type == LET || UNLIKELY(token.m_type == ESCAPED_KEYWORD && *token.m_data.ident == m_vm.propertyNames->letKeyword);
}
bool isDisallowedIdentifierAwait(const JSToken& token)
{
return isPossiblyEscapedAwait(token) && !canUseIdentifierAwait();
}
bool isAllowedIdentifierAwait(const JSToken& token)
{
return isPossiblyEscapedAwait(token) && canUseIdentifierAwait();
}
ALWAYS_INLINE bool isPossiblyEscapedAwait(const JSToken& token)
{
return token.m_type == AWAIT || UNLIKELY(token.m_type == ESCAPED_KEYWORD && *token.m_data.ident == m_vm.propertyNames->awaitKeyword);
}
ALWAYS_INLINE bool canUseIdentifierAwait()
{
return m_parserState.allowAwait && !currentScope()->isAsyncFunction() && m_scriptMode != JSParserScriptMode::Module;
}
bool isDisallowedIdentifierYield(const JSToken& token)
{
return isPossiblyEscapedYield(token) && !canUseIdentifierYield();
}
bool isAllowedIdentifierYield(const JSToken& token)
{
return isPossiblyEscapedYield(token) && canUseIdentifierYield();
}
ALWAYS_INLINE bool isPossiblyEscapedYield(const JSToken& token)
{
return token.m_type == YIELD || UNLIKELY(token.m_type == ESCAPED_KEYWORD && *token.m_data.ident == m_vm.propertyNames->yieldKeyword);
}
ALWAYS_INLINE bool canUseIdentifierYield()
{
return !strictMode() && !currentScope()->isGenerator();
}
bool matchAllowedEscapedContextualKeyword()
{
ASSERT(m_token.m_type == ESCAPED_KEYWORD);
return (*m_token.m_data.ident == m_vm.propertyNames->letKeyword && !strictMode())
|| (*m_token.m_data.ident == m_vm.propertyNames->awaitKeyword && canUseIdentifierAwait())
|| (*m_token.m_data.ident == m_vm.propertyNames->yieldKeyword && canUseIdentifierYield());
}
ALWAYS_INLINE SuperBinding adjustSuperBindingForBaseConstructor(ConstructorKind constructorKind, SuperBinding superBinding, ScopeRef functionScope)
{
return adjustSuperBindingForBaseConstructor(constructorKind, superBinding, functionScope->needsSuperBinding(), functionScope->usesEval(), functionScope->innerArrowFunctionFeatures());
}
ALWAYS_INLINE SuperBinding adjustSuperBindingForBaseConstructor(ConstructorKind constructorKind, SuperBinding superBinding, bool scopeNeedsSuperBinding, bool currentScopeUsesEval, InnerArrowFunctionCodeFeatures innerArrowFunctionFeatures)
{
SuperBinding methodSuperBinding = superBinding;
if (constructorKind == ConstructorKind::Base) {
bool isSuperUsedInInnerArrowFunction = innerArrowFunctionFeatures & SuperPropertyInnerArrowFunctionFeature;
methodSuperBinding = (scopeNeedsSuperBinding || isSuperUsedInInnerArrowFunction || currentScopeUsesEval) ? SuperBinding::Needed : SuperBinding::NotNeeded;
}
return methodSuperBinding;
}
const char* disallowedIdentifierLetReason()
{
ASSERT(strictMode());
return "in strict mode";
}
const char* disallowedIdentifierAwaitReason()
{
if (!m_parserState.allowAwait || currentScope()->isAsyncFunction())
return "in an async function";
if (m_scriptMode == JSParserScriptMode::Module)
return "in a module";
RELEASE_ASSERT_NOT_REACHED();
return nullptr;
}
const char* disallowedIdentifierYieldReason()
{
if (strictMode())
return "in strict mode";
if (currentScope()->isGenerator())
return "in a generator function";
RELEASE_ASSERT_NOT_REACHED();
return nullptr;
}
enum class FunctionParsePhase { Parameters, Body };
struct ParserState {
int assignmentCount { 0 };
int nonLHSCount { 0 };
int nonTrivialExpressionCount { 0 };
int unaryTokenStackDepth { 0 };
FunctionParsePhase functionParsePhase { FunctionParsePhase::Body };
const Identifier* lastIdentifier { nullptr };
const Identifier* lastFunctionName { nullptr };
const Identifier* lastPrivateName { nullptr };
bool allowAwait { true };
bool isParsingClassFieldInitializer { false };
};
// If you're using this directly, you probably should be using
// createSavePoint() instead.
template <class TreeBuilder>
ALWAYS_INLINE ParserState internalSaveParserState(TreeBuilder& context)
{
auto parserState = m_parserState;
parserState.unaryTokenStackDepth = context.unaryTokenStackDepth();
return parserState;
}
template <class TreeBuilder>
ALWAYS_INLINE void restoreParserState(TreeBuilder& context, const ParserState& state)
{
m_parserState = state;
context.setUnaryTokenStackDepth(m_parserState.unaryTokenStackDepth);
}
struct LexerState {
int startOffset;
unsigned oldLineStartOffset;
unsigned oldLastLineNumber;
unsigned oldLineNumber;
bool hasLineTerminatorBeforeToken;
};
// If you're using this directly, you probably should be using
// createSavePoint() instead.
// i.e, if you parse any kind of AssignmentExpression between
// saving/restoring, you should definitely not be using this directly.
ALWAYS_INLINE LexerState internalSaveLexerState()
{
LexerState result;
result.startOffset = m_token.m_location.startOffset;
result.oldLineStartOffset = m_token.m_location.lineStartOffset;
result.oldLastLineNumber = m_lexer->lastLineNumber();
result.oldLineNumber = m_lexer->lineNumber();
result.hasLineTerminatorBeforeToken = m_lexer->hasLineTerminatorBeforeToken();
ASSERT(static_cast<unsigned>(result.startOffset) >= result.oldLineStartOffset);
return result;
}
ALWAYS_INLINE void restoreLexerState(const LexerState& lexerState)
{
// setOffset clears lexer errors.
m_lexer->setOffset(lexerState.startOffset, lexerState.oldLineStartOffset);
m_lexer->setLineNumber(lexerState.oldLineNumber);
m_lexer->setHasLineTerminatorBeforeToken(lexerState.hasLineTerminatorBeforeToken);
nextWithoutClearingLineTerminator();
m_lexer->setLastLineNumber(lexerState.oldLastLineNumber);
}
struct SavePoint {
ParserState parserState;
LexerState lexerState;
};
struct SavePointWithError : public SavePoint {
bool lexerError;
String lexerErrorMessage;
String parserErrorMessage;
};
template <class TreeBuilder>
ALWAYS_INLINE void internalSaveState(TreeBuilder& context, SavePoint& savePoint)
{
savePoint.parserState = internalSaveParserState(context);
savePoint.lexerState = internalSaveLexerState();
}
template <class TreeBuilder>
ALWAYS_INLINE SavePointWithError swapSavePointForError(TreeBuilder& context, SavePoint& oldSavePoint)
{
SavePointWithError savePoint;
internalSaveState(context, savePoint);
savePoint.lexerError = m_lexer->sawError();
savePoint.lexerErrorMessage = m_lexer->getErrorMessage();
savePoint.parserErrorMessage = m_errorMessage;
// Make sure we set our new savepoints unary stack to what oldSavePoint had as it currently may contain stale info.
savePoint.parserState.unaryTokenStackDepth = oldSavePoint.parserState.unaryTokenStackDepth;
restoreSavePoint(context, oldSavePoint);
return savePoint;
}
template <class TreeBuilder>
ALWAYS_INLINE SavePoint createSavePoint(TreeBuilder& context)
{
ASSERT(!hasError());
SavePoint savePoint;
internalSaveState(context, savePoint);
return savePoint;
}
template <class TreeBuilder>
ALWAYS_INLINE void internalRestoreState(TreeBuilder& context, const SavePoint& savePoint)
{
restoreLexerState(savePoint.lexerState);
restoreParserState(context, savePoint.parserState);
}
template <class TreeBuilder>
ALWAYS_INLINE void restoreSavePointWithError(TreeBuilder& context, const SavePointWithError& savePoint)
{
internalRestoreState(context, savePoint);
m_lexer->setSawError(savePoint.lexerError);
m_lexer->setErrorMessage(savePoint.lexerErrorMessage);
m_errorMessage = savePoint.parserErrorMessage;
}
template <class TreeBuilder>
ALWAYS_INLINE void restoreSavePoint(TreeBuilder& context, const SavePoint& savePoint)
{
internalRestoreState(context, savePoint);
m_errorMessage = String();
}
VM& m_vm;
const SourceCode* m_source;
ParserArena m_parserArena;
std::unique_ptr<LexerType> m_lexer;
ParserState m_parserState;
bool m_hasStackOverflow;
String m_errorMessage;
JSToken m_token;
bool m_allowsIn;
JSTextPosition m_lastTokenEndPosition;
int m_statementDepth;
RefPtr<SourceProviderCache> m_functionCache;
bool m_parsingBuiltin;
SourceParseMode m_parseMode;
JSParserScriptMode m_scriptMode;
SuperBinding m_superBinding;
ConstructorKind m_defaultConstructorKindForTopLevelFunction;
ExpressionErrorClassifier* m_expressionErrorClassifier;
bool m_isEvalContext;
bool m_immediateParentAllowsFunctionDeclarationInStatement;
RefPtr<ModuleScopeData> m_moduleScopeData;
DebuggerParseData* m_debuggerParseData;
CallOrApplyDepthScope* m_callOrApplyDepthScope { nullptr };
bool m_isInsideOrdinaryFunction;
bool m_seenTaggedTemplateInNonReparsingFunctionMode { false };
bool m_seenPrivateNameUseInNonReparsingFunctionMode { false };
};
template <typename LexerType>
template <class ParsedNode>
std::unique_ptr<ParsedNode> Parser<LexerType>::parse(ParserError& error, const Identifier& calleeName, ParsingContext parsingContext, std::optional<int> functionConstructorParametersEndPosition, const PrivateNameEnvironment* parentScopePrivateNames, const FixedVector<JSTextPosition>* classFieldLocations)
{
int errLine;
String errMsg;
SourceParseMode parseMode = sourceParseMode();
if (ParsedNode::scopeIsFunction)
m_lexer->setIsReparsingFunction();
errLine = -1;
errMsg = String();
JSTokenLocation startLocation(tokenLocation());
ASSERT(m_source->startColumn() > OrdinalNumber::beforeFirst());
unsigned startColumn = m_source->startColumn().zeroBasedInt();
auto parseResult = parseInner(calleeName, parsingContext, functionConstructorParametersEndPosition, classFieldLocations, parentScopePrivateNames);
int lineNumber = m_lexer->lineNumber();
bool lexError = m_lexer->sawError();
String lexErrorMessage = lexError ? m_lexer->getErrorMessage() : String();
ASSERT(lexErrorMessage.isNull() != lexError);
m_lexer->clear();
if (!parseResult || lexError) {
errLine = lineNumber;
errMsg = !lexErrorMessage.isNull() ? lexErrorMessage : parseResult.error();
}
std::unique_ptr<ParsedNode> result;
if (parseResult) {
JSTokenLocation endLocation;
endLocation.line = m_lexer->lineNumber();
endLocation.lineStartOffset = m_lexer->currentLineStartOffset();
endLocation.startOffset = m_lexer->currentOffset();
unsigned endColumn = endLocation.startOffset - endLocation.lineStartOffset;
result = makeUnique<ParsedNode>(m_parserArena,
startLocation,
endLocation,
startColumn,
endColumn,
parseResult.value().sourceElements,
WTFMove(parseResult.value().varDeclarations),
WTFMove(parseResult.value().functionDeclarations),
WTFMove(parseResult.value().lexicalVariables),
WTFMove(parseResult.value().sloppyModeHoistedFunctions),
parseResult.value().parameters,
*m_source,
parseResult.value().features,
currentScope()->lexicalScopeFeatures(),
currentScope()->innerArrowFunctionFeatures(),
parseResult.value().numConstants,
WTFMove(m_moduleScopeData));
result->setLoc(m_source->firstLine().oneBasedInt(), m_lexer->lineNumber(), m_lexer->currentOffset(), m_lexer->currentLineStartOffset());
result->setEndOffset(m_lexer->currentOffset());
if (!isFunctionParseMode(parseMode)) {
m_source->provider()->setSourceURLDirective(m_lexer->sourceURLDirective());
m_source->provider()->setSourceMappingURLDirective(m_lexer->sourceMappingURLDirective());
}
} else {
// We can never see a syntax error when reparsing a function, since we should have
// reported the error when parsing the containing program or eval code. So if we're
// parsing a function body node, we assume that what actually happened here is that
// we ran out of stack while parsing. If we see an error while parsing eval or program
// code we assume that it was a syntax error since running out of stack is much less
// likely, and we are currently unable to distinguish between the two cases.
if (isFunctionMetadataNode(static_cast<ParsedNode*>(nullptr)) || m_hasStackOverflow)
error = ParserError(ParserError::StackOverflow, ParserError::SyntaxErrorNone, m_token);
else {
ParserError::SyntaxErrorType errorType = ParserError::SyntaxErrorIrrecoverable;
if (m_token.m_type == EOFTOK)
errorType = ParserError::SyntaxErrorRecoverable;
else if (m_token.m_type & UnterminatedCanBeErrorTokenFlag) {
// Treat multiline capable unterminated literals as recoverable.
if (m_token.m_type == UNTERMINATED_MULTILINE_COMMENT_ERRORTOK || m_token.m_type == UNTERMINATED_TEMPLATE_LITERAL_ERRORTOK)
errorType = ParserError::SyntaxErrorRecoverable;
else
errorType = ParserError::SyntaxErrorUnterminatedLiteral;
}
if (isEvalNode<ParsedNode>())
error = ParserError(ParserError::EvalError, errorType, m_token, errMsg, errLine);
else
error = ParserError(ParserError::SyntaxError, errorType, m_token, errMsg, errLine);
}
}
return result;
}
template <class ParsedNode>
std::unique_ptr<ParsedNode> parse(
VM& vm, const SourceCode& source,
const Identifier& name, JSParserBuiltinMode builtinMode,
JSParserStrictMode strictMode, JSParserScriptMode scriptMode, SourceParseMode parseMode, SuperBinding superBinding,
ParserError& error, JSTextPosition* positionBeforeLastNewline = nullptr,
ConstructorKind defaultConstructorKindForTopLevelFunction = ConstructorKind::None,
DerivedContextType derivedContextType = DerivedContextType::None,
EvalContextType evalContextType = EvalContextType::None,
DebuggerParseData* debuggerParseData = nullptr,
const PrivateNameEnvironment* parentScopePrivateNames = nullptr,
const FixedVector<JSTextPosition>* classFieldLocations = nullptr,
bool isInsideOrdinaryFunction = false)
{
ASSERT(!source.provider()->source().isNull());
MonotonicTime before;
if (UNLIKELY(Options::reportParseTimes()))
before = MonotonicTime::now();
std::unique_ptr<ParsedNode> result;
if (source.provider()->source().is8Bit()) {
Parser<Lexer<LChar>> parser(vm, source, builtinMode, strictMode, scriptMode, parseMode, superBinding, defaultConstructorKindForTopLevelFunction, derivedContextType, isEvalNode<ParsedNode>(), evalContextType, debuggerParseData, isInsideOrdinaryFunction);
result = parser.parse<ParsedNode>(error, name, isEvalNode<ParsedNode>() ? ParsingContext::Eval : ParsingContext::Program, std::nullopt, parentScopePrivateNames, classFieldLocations);
if (positionBeforeLastNewline)
*positionBeforeLastNewline = parser.positionBeforeLastNewline();
if (builtinMode == JSParserBuiltinMode::Builtin) {
if (!result) {
ASSERT(error.isValid());
if (error.type() != ParserError::StackOverflow)
dataLogLn("Unexpected error compiling builtin: ", error.message(), " on line ", error.line(), ".");
}
}
} else {
ASSERT_WITH_MESSAGE(defaultConstructorKindForTopLevelFunction == ConstructorKind::None, "BuiltinExecutables's special constructors should always use a 8-bit string");
Parser<Lexer<UChar>> parser(vm, source, builtinMode, strictMode, scriptMode, parseMode, superBinding, defaultConstructorKindForTopLevelFunction, derivedContextType, isEvalNode<ParsedNode>(), evalContextType, debuggerParseData, isInsideOrdinaryFunction);
result = parser.parse<ParsedNode>(error, name, isEvalNode<ParsedNode>() ? ParsingContext::Eval : ParsingContext::Program, std::nullopt, parentScopePrivateNames, classFieldLocations);
if (positionBeforeLastNewline)
*positionBeforeLastNewline = parser.positionBeforeLastNewline();
}
if (UNLIKELY(Options::countParseTimes()))
globalParseCount++;
if (UNLIKELY(Options::reportParseTimes())) {
MonotonicTime after = MonotonicTime::now();
ParseHash hash(source);
dataLogLn(result ? "Parsed #" : "Failed to parse #", hash.hashForCall(), "/#", hash.hashForConstruct(), " in ", (after - before).milliseconds(), " ms.");
}
return result;
}
inline std::unique_ptr<ProgramNode> parseFunctionForFunctionConstructor(VM& vm, const SourceCode& source, ParserError& error, JSTextPosition* positionBeforeLastNewline, std::optional<int> functionConstructorParametersEndPosition)
{
ASSERT(!source.provider()->source().isNull());
MonotonicTime before;
if (UNLIKELY(Options::reportParseTimes()))
before = MonotonicTime::now();
Identifier name;
bool isEvalNode = false;
std::unique_ptr<ProgramNode> result;
if (source.provider()->source().is8Bit()) {
Parser<Lexer<LChar>> parser(vm, source, JSParserBuiltinMode::NotBuiltin, JSParserStrictMode::NotStrict, JSParserScriptMode::Classic, SourceParseMode::ProgramMode, SuperBinding::NotNeeded, ConstructorKind::None, DerivedContextType::None, isEvalNode, EvalContextType::None, nullptr);
result = parser.parse<ProgramNode>(error, name, ParsingContext::FunctionConstructor, functionConstructorParametersEndPosition);
if (positionBeforeLastNewline)
*positionBeforeLastNewline = parser.positionBeforeLastNewline();
} else {
Parser<Lexer<UChar>> parser(vm, source, JSParserBuiltinMode::NotBuiltin, JSParserStrictMode::NotStrict, JSParserScriptMode::Classic, SourceParseMode::ProgramMode, SuperBinding::NotNeeded, ConstructorKind::None, DerivedContextType::None, isEvalNode, EvalContextType::None, nullptr);
result = parser.parse<ProgramNode>(error, name, ParsingContext::FunctionConstructor, functionConstructorParametersEndPosition);
if (positionBeforeLastNewline)
*positionBeforeLastNewline = parser.positionBeforeLastNewline();
}
if (UNLIKELY(Options::countParseTimes()))
globalParseCount++;
if (UNLIKELY(Options::reportParseTimes())) {
MonotonicTime after = MonotonicTime::now();
ParseHash hash(source);
dataLogLn(result ? "Parsed #" : "Failed to parse #", hash.hashForCall(), "/#", hash.hashForConstruct(), " in ", (after - before).milliseconds(), " ms.");
}
return result;
}
} // namespace