Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1226 insertions, 0 deletions

diff --git a/js/src/frontend/FullParseHandler.h b/js/src/frontend/FullParseHandler.h
new file mode 100644
index 0000000000..384d16b7d8
--- /dev/null
+++ b/js/src/frontend/FullParseHandler.h
@@ -0,0 +1,1226 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef frontend_FullParseHandler_h
+#define frontend_FullParseHandler_h
+
+#include "mozilla/Maybe.h"   // mozilla::Maybe
+#include "mozilla/Result.h"  // mozilla::Result, mozilla::UnusedZero
+#include "mozilla/Try.h"     // MOZ_TRY*
+
+#include <cstddef>  // std::nullptr_t
+#include <string.h>
+
+#include "jstypes.h"
+
+#include "frontend/CompilationStencil.h"  // CompilationState
+#include "frontend/FunctionSyntaxKind.h"  // FunctionSyntaxKind
+#include "frontend/NameAnalysisTypes.h"   // PrivateNameKind
+#include "frontend/ParseNode.h"
+#include "frontend/Parser-macros.h"  // MOZ_TRY_VAR_OR_RETURN
+#include "frontend/ParserAtom.h"     // TaggedParserAtomIndex
+#include "frontend/SharedContext.h"
+#include "frontend/Stencil.h"
+
+template <>
+struct mozilla::detail::UnusedZero<js::frontend::ParseNode*> {
+  static const bool value = true;
+};
+
+#define DEFINE_UNUSED_ZERO(typeName)                            \
+  template <>                                                   \
+  struct mozilla::detail::UnusedZero<js::frontend::typeName*> { \
+    static const bool value = true;                             \
+  };
+FOR_EACH_PARSENODE_SUBCLASS(DEFINE_UNUSED_ZERO)
+#undef DEFINE_UNUSED_ZERO
+
+namespace js {
+namespace frontend {
+
+class TokenStreamAnyChars;
+
+// Parse handler used when generating a full parse tree for all code which the
+// parser encounters.
+class FullParseHandler {
+  ParseNodeAllocator allocator;
+
+  ParseNode* allocParseNode(size_t size) {
+    return static_cast<ParseNode*>(allocator.allocNode(size));
+  }
+
+  // If this is a full parse to construct the bytecode for a function that
+  // was previously lazily parsed, we still don't want to full parse the
+  // inner functions. These members are used for this functionality:
+  //
+  // - reuseGCThings if ture it means that the following fields are valid.
+  // - gcThingsData holds an incomplete stencil-like copy of inner functions as
+  //   well as atoms.
+  // - scriptData and scriptExtra_ hold information necessary to locate inner
+  //   functions to skip over each.
+  // - lazyInnerFunctionIndex is used as we skip over inner functions
+  //   (see skipLazyInnerFunction),
+  // - lazyClosedOverBindingIndex is used to synchronize binding computation
+  //   with the scope traversal.
+  //   (see propagateFreeNamesAndMarkClosedOverBindings),
+  const CompilationSyntaxParseCache& previousParseCache_;
+
+  size_t lazyInnerFunctionIndex;
+  size_t lazyClosedOverBindingIndex;
+
+  bool reuseGCThings;
+
+  /* new_ methods for creating parse nodes. These report OOM on context. */
+  JS_DECLARE_NEW_METHODS(new_, allocParseNode, inline)
+
+ public:
+  using NodeError = ParseNodeError;
+
+  using Node = ParseNode*;
+  using NodeResult = ParseNodeResult;
+  using NodeErrorResult = mozilla::GenericErrorResult<NodeError>;
+
+#define DECLARE_TYPE(typeName)      \
+  using typeName##Type = typeName*; \
+  using typeName##Result = mozilla::Result<typeName*, NodeError>;
+  FOR_EACH_PARSENODE_SUBCLASS(DECLARE_TYPE)
+#undef DECLARE_TYPE
+
+  template <class T, typename... Args>
+  inline mozilla::Result<T*, NodeError> newResult(Args&&... args) {
+    auto* node = new_<T>(std::forward<Args>(args)...);
+    if (!node) {
+      return mozilla::Result<T*, NodeError>(NodeError());
+    }
+    return node;
+  }
+
+  using NullNode = std::nullptr_t;
+
+  bool isPropertyOrPrivateMemberAccess(Node node) {
+    return node->isKind(ParseNodeKind::DotExpr) ||
+           node->isKind(ParseNodeKind::ElemExpr) ||
+           node->isKind(ParseNodeKind::PrivateMemberExpr);
+  }
+
+  bool isOptionalPropertyOrPrivateMemberAccess(Node node) {
+    return node->isKind(ParseNodeKind::OptionalDotExpr) ||
+           node->isKind(ParseNodeKind::OptionalElemExpr) ||
+           node->isKind(ParseNodeKind::PrivateMemberExpr);
+  }
+
+  bool isFunctionCall(Node node) {
+    // Note: super() is a special form, *not* a function call.
+    return node->isKind(ParseNodeKind::CallExpr);
+  }
+
+  static bool isUnparenthesizedDestructuringPattern(Node node) {
+    return !node->isInParens() && (node->isKind(ParseNodeKind::ObjectExpr) ||
+                                   node->isKind(ParseNodeKind::ArrayExpr));
+  }
+
+  static bool isParenthesizedDestructuringPattern(Node node) {
+    // Technically this isn't a destructuring pattern at all -- the grammar
+    // doesn't treat it as such.  But we need to know when this happens to
+    // consider it a SyntaxError rather than an invalid-left-hand-side
+    // ReferenceError.
+    return node->isInParens() && (node->isKind(ParseNodeKind::ObjectExpr) ||
+                                  node->isKind(ParseNodeKind::ArrayExpr));
+  }
+
+  FullParseHandler(FrontendContext* fc, CompilationState& compilationState)
+      : allocator(fc, compilationState.parserAllocScope.alloc()),
+        previousParseCache_(compilationState.previousParseCache),
+        lazyInnerFunctionIndex(0),
+        lazyClosedOverBindingIndex(0),
+        reuseGCThings(compilationState.input.isDelazifying()) {}
+
+  static NullNode null() { return NullNode(); }
+  static constexpr NodeErrorResult errorResult() {
+    return NodeErrorResult(NodeError());
+  }
+
+#define DECLARE_AS(typeName)                      \
+  static typeName##Type as##typeName(Node node) { \
+    return &node->as<typeName>();                 \
+  }
+  FOR_EACH_PARSENODE_SUBCLASS(DECLARE_AS)
+#undef DECLARE_AS
+
+  NameNodeResult newName(TaggedParserAtomIndex name, const TokenPos& pos) {
+    return newResult<NameNode>(ParseNodeKind::Name, name, pos);
+  }
+
+  UnaryNodeResult newComputedName(Node expr, uint32_t begin, uint32_t end) {
+    TokenPos pos(begin, end);
+    return newResult<UnaryNode>(ParseNodeKind::ComputedName, pos, expr);
+  }
+
+  UnaryNodeResult newSyntheticComputedName(Node expr, uint32_t begin,
+                                           uint32_t end) {
+    TokenPos pos(begin, end);
+    UnaryNode* node;
+    MOZ_TRY_VAR(node,
+                newResult<UnaryNode>(ParseNodeKind::ComputedName, pos, expr));
+    node->setSyntheticComputedName();
+    return node;
+  }
+
+  NameNodeResult newObjectLiteralPropertyName(TaggedParserAtomIndex atom,
+                                              const TokenPos& pos) {
+    return newResult<NameNode>(ParseNodeKind::ObjectPropertyName, atom, pos);
+  }
+
+  NameNodeResult newPrivateName(TaggedParserAtomIndex atom,
+                                const TokenPos& pos) {
+    return newResult<NameNode>(ParseNodeKind::PrivateName, atom, pos);
+  }
+
+  NumericLiteralResult newNumber(double value, DecimalPoint decimalPoint,
+                                 const TokenPos& pos) {
+    return newResult<NumericLiteral>(value, decimalPoint, pos);
+  }
+
+  BigIntLiteralResult newBigInt(BigIntIndex index, bool isZero,
+                                const TokenPos& pos) {
+    return newResult<BigIntLiteral>(index, isZero, pos);
+  }
+
+  BooleanLiteralResult newBooleanLiteral(bool cond, const TokenPos& pos) {
+    return newResult<BooleanLiteral>(cond, pos);
+  }
+
+  NameNodeResult newStringLiteral(TaggedParserAtomIndex atom,
+                                  const TokenPos& pos) {
+    return newResult<NameNode>(ParseNodeKind::StringExpr, atom, pos);
+  }
+
+  NameNodeResult newTemplateStringLiteral(TaggedParserAtomIndex atom,
+                                          const TokenPos& pos) {
+    return newResult<NameNode>(ParseNodeKind::TemplateStringExpr, atom, pos);
+  }
+
+  CallSiteNodeResult newCallSiteObject(uint32_t begin) {
+    CallSiteNode* callSiteObj;
+    MOZ_TRY_VAR(callSiteObj, newResult<CallSiteNode>(begin));
+
+    ListNode* rawNodes;
+    MOZ_TRY_VAR(rawNodes, newArrayLiteral(callSiteObj->pn_pos.begin));
+
+    addArrayElement(callSiteObj, rawNodes);
+
+    return callSiteObj;
+  }
+
+  void addToCallSiteObject(CallSiteNodeType callSiteObj, Node rawNode,
+                           Node cookedNode) {
+    MOZ_ASSERT(callSiteObj->isKind(ParseNodeKind::CallSiteObj));
+    MOZ_ASSERT(rawNode->isKind(ParseNodeKind::TemplateStringExpr));
+    MOZ_ASSERT(cookedNode->isKind(ParseNodeKind::TemplateStringExpr) ||
+               cookedNode->isKind(ParseNodeKind::RawUndefinedExpr));
+
+    addArrayElement(callSiteObj, cookedNode);
+    addArrayElement(callSiteObj->rawNodes(), rawNode);
+
+    /*
+     * We don't know when the last noSubstTemplate will come in, and we
+     * don't want to deal with this outside this method
+     */
+    setEndPosition(callSiteObj, callSiteObj->rawNodes());
+  }
+
+  ThisLiteralResult newThisLiteral(const TokenPos& pos, Node thisName) {
+    return newResult<ThisLiteral>(pos, thisName);
+  }
+
+  NullLiteralResult newNullLiteral(const TokenPos& pos) {
+    return newResult<NullLiteral>(pos);
+  }
+
+  RawUndefinedLiteralResult newRawUndefinedLiteral(const TokenPos& pos) {
+    return newResult<RawUndefinedLiteral>(pos);
+  }
+
+  RegExpLiteralResult newRegExp(RegExpIndex index, const TokenPos& pos) {
+    return newResult<RegExpLiteral>(index, pos);
+  }
+
+  ConditionalExpressionResult newConditional(Node cond, Node thenExpr,
+                                             Node elseExpr) {
+    return newResult<ConditionalExpression>(cond, thenExpr, elseExpr);
+  }
+
+  UnaryNodeResult newDelete(uint32_t begin, Node expr) {
+    if (expr->isKind(ParseNodeKind::Name)) {
+      return newUnary(ParseNodeKind::DeleteNameExpr, begin, expr);
+    }
+
+    if (expr->isKind(ParseNodeKind::DotExpr)) {
+      return newUnary(ParseNodeKind::DeletePropExpr, begin, expr);
+    }
+
+    if (expr->isKind(ParseNodeKind::ElemExpr)) {
+      return newUnary(ParseNodeKind::DeleteElemExpr, begin, expr);
+    }
+
+    if (expr->isKind(ParseNodeKind::OptionalChain)) {
+      Node kid = expr->as<UnaryNode>().kid();
+      // Handle property deletion explicitly. OptionalCall is handled
+      // via DeleteExpr.
+      if (kid->isKind(ParseNodeKind::DotExpr) ||
+          kid->isKind(ParseNodeKind::OptionalDotExpr) ||
+          kid->isKind(ParseNodeKind::ElemExpr) ||
+          kid->isKind(ParseNodeKind::OptionalElemExpr)) {
+        return newUnary(ParseNodeKind::DeleteOptionalChainExpr, begin, kid);
+      }
+    }
+
+    return newUnary(ParseNodeKind::DeleteExpr, begin, expr);
+  }
+
+  UnaryNodeResult newTypeof(uint32_t begin, Node kid) {
+    ParseNodeKind pnk = kid->isKind(ParseNodeKind::Name)
+                            ? ParseNodeKind::TypeOfNameExpr
+                            : ParseNodeKind::TypeOfExpr;
+    return newUnary(pnk, begin, kid);
+  }
+
+  UnaryNodeResult newUnary(ParseNodeKind kind, uint32_t begin, Node kid) {
+    TokenPos pos(begin, kid->pn_pos.end);
+    return newResult<UnaryNode>(kind, pos, kid);
+  }
+
+  UnaryNodeResult newUpdate(ParseNodeKind kind, uint32_t begin, Node kid) {
+    TokenPos pos(begin, kid->pn_pos.end);
+    return newResult<UnaryNode>(kind, pos, kid);
+  }
+
+  UnaryNodeResult newSpread(uint32_t begin, Node kid) {
+    TokenPos pos(begin, kid->pn_pos.end);
+    return newResult<UnaryNode>(ParseNodeKind::Spread, pos, kid);
+  }
+
+ private:
+  BinaryNodeResult newBinary(ParseNodeKind kind, Node left, Node right) {
+    TokenPos pos(left->pn_pos.begin, right->pn_pos.end);
+    return newResult<BinaryNode>(kind, pos, left, right);
+  }
+
+ public:
+  NodeResult appendOrCreateList(ParseNodeKind kind, Node left, Node right,
+                                ParseContext* pc) {
+    return ParseNode::appendOrCreateList(kind, left, right, this, pc);
+  }
+
+  // Expressions
+
+  ListNodeResult newArrayLiteral(uint32_t begin) {
+    return newResult<ListNode>(ParseNodeKind::ArrayExpr,
+                               TokenPos(begin, begin + 1));
+  }
+
+  [[nodiscard]] bool addElision(ListNodeType literal, const TokenPos& pos) {
+    MOZ_ASSERT(literal->isKind(ParseNodeKind::ArrayExpr));
+
+    NullaryNode* elision;
+    MOZ_TRY_VAR_OR_RETURN(
+        elision, newResult<NullaryNode>(ParseNodeKind::Elision, pos), false);
+    addList(/* list = */ literal, /* kid = */ elision);
+    literal->setHasNonConstInitializer();
+    return true;
+  }
+
+  [[nodiscard]] bool addSpreadElement(ListNodeType literal, uint32_t begin,
+                                      Node inner) {
+    MOZ_ASSERT(
+        literal->isKind(ParseNodeKind::ArrayExpr) ||
+        IF_RECORD_TUPLE(literal->isKind(ParseNodeKind::TupleExpr), false));
+
+    UnaryNodeType spread;
+    MOZ_TRY_VAR_OR_RETURN(spread, newSpread(begin, inner), false);
+    addList(/* list = */ literal, /* kid = */ spread);
+    literal->setHasNonConstInitializer();
+    return true;
+  }
+
+  void addArrayElement(ListNodeType literal, Node element) {
+    MOZ_ASSERT(
+        literal->isKind(ParseNodeKind::ArrayExpr) ||
+        literal->isKind(ParseNodeKind::CallSiteObj) ||
+        IF_RECORD_TUPLE(literal->isKind(ParseNodeKind::TupleExpr), false));
+    if (!element->isConstant()) {
+      literal->setHasNonConstInitializer();
+    }
+    addList(/* list = */ literal, /* kid = */ element);
+  }
+
+  CallNodeResult newCall(Node callee, ListNodeType args, JSOp callOp) {
+    return newResult<CallNode>(ParseNodeKind::CallExpr, callOp, callee, args);
+  }
+
+  CallNodeResult newOptionalCall(Node callee, ListNodeType args, JSOp callOp) {
+    return newResult<CallNode>(ParseNodeKind::OptionalCallExpr, callOp, callee,
+                               args);
+  }
+
+  ListNodeResult newArguments(const TokenPos& pos) {
+    return newResult<ListNode>(ParseNodeKind::Arguments, pos);
+  }
+
+  CallNodeResult newSuperCall(Node callee, ListNodeType args, bool isSpread) {
+    return newResult<CallNode>(
+        ParseNodeKind::SuperCallExpr,
+        isSpread ? JSOp::SpreadSuperCall : JSOp::SuperCall, callee, args);
+  }
+
+  CallNodeResult newTaggedTemplate(Node tag, ListNodeType args, JSOp callOp) {
+    return newResult<CallNode>(ParseNodeKind::TaggedTemplateExpr, callOp, tag,
+                               args);
+  }
+
+  ListNodeResult newObjectLiteral(uint32_t begin) {
+    return newResult<ListNode>(ParseNodeKind::ObjectExpr,
+                               TokenPos(begin, begin + 1));
+  }
+
+#ifdef ENABLE_RECORD_TUPLE
+  ListNodeResult newRecordLiteral(uint32_t begin) {
+    return newResult<ListNode>(ParseNodeKind::RecordExpr,
+                               TokenPos(begin, begin + 1));
+  }
+
+  ListNodeResult newTupleLiteral(uint32_t begin) {
+    return newResult<ListNode>(ParseNodeKind::TupleExpr,
+                               TokenPos(begin, begin + 1));
+  }
+#endif
+
+  ClassNodeResult newClass(Node name, Node heritage,
+                           LexicalScopeNodeType memberBlock,
+#ifdef ENABLE_DECORATORS
+                           ListNodeType decorators,
+                           FunctionNodeType addInitializerFunction,
+#endif
+                           const TokenPos& pos) {
+    return newResult<ClassNode>(name, heritage, memberBlock,
+#ifdef ENABLE_DECORATORS
+                                decorators, addInitializerFunction,
+#endif
+                                pos);
+  }
+  ListNodeResult newClassMemberList(uint32_t begin) {
+    return newResult<ListNode>(ParseNodeKind::ClassMemberList,
+                               TokenPos(begin, begin + 1));
+  }
+  ClassNamesResult newClassNames(Node outer, Node inner, const TokenPos& pos) {
+    return newResult<ClassNames>(outer, inner, pos);
+  }
+  NewTargetNodeResult newNewTarget(NullaryNodeType newHolder,
+                                   NullaryNodeType targetHolder,
+                                   NameNodeType newTargetName) {
+    return newResult<NewTargetNode>(newHolder, targetHolder, newTargetName);
+  }
+  NullaryNodeResult newPosHolder(const TokenPos& pos) {
+    return newResult<NullaryNode>(ParseNodeKind::PosHolder, pos);
+  }
+  UnaryNodeResult newSuperBase(Node thisName, const TokenPos& pos) {
+    return newResult<UnaryNode>(ParseNodeKind::SuperBase, pos, thisName);
+  }
+  [[nodiscard]] bool addPrototypeMutation(ListNodeType literal, uint32_t begin,
+                                          Node expr) {
+    MOZ_ASSERT(literal->isKind(ParseNodeKind::ObjectExpr));
+
+    // Object literals with mutated [[Prototype]] are non-constant so that
+    // singleton objects will have Object.prototype as their [[Prototype]].
+    literal->setHasNonConstInitializer();
+
+    UnaryNode* mutation;
+    MOZ_TRY_VAR_OR_RETURN(
+        mutation, newUnary(ParseNodeKind::MutateProto, begin, expr), false);
+    addList(/* list = */ literal, /* kid = */ mutation);
+    return true;
+  }
+
+  BinaryNodeResult newPropertyDefinition(Node key, Node val) {
+    MOZ_ASSERT(isUsableAsObjectPropertyName(key));
+    checkAndSetIsDirectRHSAnonFunction(val);
+    return newResult<PropertyDefinition>(key, val, AccessorType::None);
+  }
+
+  void addPropertyDefinition(ListNodeType literal, BinaryNodeType propdef) {
+    MOZ_ASSERT(
+        literal->isKind(ParseNodeKind::ObjectExpr) ||
+        IF_RECORD_TUPLE(literal->isKind(ParseNodeKind::RecordExpr), false));
+    MOZ_ASSERT(propdef->isKind(ParseNodeKind::PropertyDefinition));
+
+    if (!propdef->right()->isConstant()) {
+      literal->setHasNonConstInitializer();
+    }
+
+    addList(/* list = */ literal, /* kid = */ propdef);
+  }
+
+  [[nodiscard]] bool addPropertyDefinition(ListNodeType literal, Node key,
+                                           Node val) {
+    BinaryNode* propdef;
+    MOZ_TRY_VAR_OR_RETURN(propdef, newPropertyDefinition(key, val), false);
+    addPropertyDefinition(literal, propdef);
+    return true;
+  }
+
+  [[nodiscard]] bool addShorthand(ListNodeType literal, NameNodeType name,
+                                  NameNodeType expr) {
+    MOZ_ASSERT(
+        literal->isKind(ParseNodeKind::ObjectExpr) ||
+        IF_RECORD_TUPLE(literal->isKind(ParseNodeKind::RecordExpr), false));
+    MOZ_ASSERT(name->isKind(ParseNodeKind::ObjectPropertyName));
+    MOZ_ASSERT(expr->isKind(ParseNodeKind::Name));
+    MOZ_ASSERT(name->atom() == expr->atom());
+
+    literal->setHasNonConstInitializer();
+    BinaryNode* propdef;
+    MOZ_TRY_VAR_OR_RETURN(
+        propdef, newBinary(ParseNodeKind::Shorthand, name, expr), false);
+    addList(/* list = */ literal, /* kid = */ propdef);
+    return true;
+  }
+
+  [[nodiscard]] bool addSpreadProperty(ListNodeType literal, uint32_t begin,
+                                       Node inner) {
+    MOZ_ASSERT(
+        literal->isKind(ParseNodeKind::ObjectExpr) ||
+        IF_RECORD_TUPLE(literal->isKind(ParseNodeKind::RecordExpr), false));
+
+    literal->setHasNonConstInitializer();
+    ParseNode* spread;
+    MOZ_TRY_VAR_OR_RETURN(spread, newSpread(begin, inner), false);
+    addList(/* list = */ literal, /* kid = */ spread);
+    return true;
+  }
+
+  [[nodiscard]] bool addObjectMethodDefinition(ListNodeType literal, Node key,
+                                               FunctionNodeType funNode,
+                                               AccessorType atype) {
+    literal->setHasNonConstInitializer();
+
+    checkAndSetIsDirectRHSAnonFunction(funNode);
+
+    ParseNode* propdef;
+    MOZ_TRY_VAR_OR_RETURN(
+        propdef, newObjectMethodOrPropertyDefinition(key, funNode, atype),
+        false);
+    addList(/* list = */ literal, /* kid = */ propdef);
+    return true;
+  }
+
+  [[nodiscard]] ClassMethodResult newDefaultClassConstructor(
+      Node key, FunctionNodeType funNode) {
+    MOZ_ASSERT(isUsableAsObjectPropertyName(key));
+
+    checkAndSetIsDirectRHSAnonFunction(funNode);
+
+    return newResult<ClassMethod>(
+        ParseNodeKind::DefaultConstructor, key, funNode, AccessorType::None,
+        /* isStatic = */ false, /* initializeIfPrivate = */ nullptr
+#ifdef ENABLE_DECORATORS
+        ,
+        /* decorators = */ nullptr
+#endif
+    );
+  }
+
+  [[nodiscard]] ClassMethodResult newClassMethodDefinition(
+      Node key, FunctionNodeType funNode, AccessorType atype, bool isStatic,
+      mozilla::Maybe<FunctionNodeType> initializerIfPrivate
+#ifdef ENABLE_DECORATORS
+      ,
+      ListNodeType decorators
+#endif
+  ) {
+    MOZ_ASSERT(isUsableAsObjectPropertyName(key));
+
+    checkAndSetIsDirectRHSAnonFunction(funNode);
+
+    if (initializerIfPrivate.isSome()) {
+      return newResult<ClassMethod>(ParseNodeKind::ClassMethod, key, funNode,
+                                    atype, isStatic,
+                                    initializerIfPrivate.value()
+#ifdef ENABLE_DECORATORS
+                                        ,
+                                    decorators
+#endif
+      );
+    }
+    return newResult<ClassMethod>(ParseNodeKind::ClassMethod, key, funNode,
+                                  atype, isStatic,
+                                  /* initializeIfPrivate = */ nullptr
+#ifdef ENABLE_DECORATORS
+                                  ,
+                                  decorators
+#endif
+    );
+  }
+
+  [[nodiscard]] ClassFieldResult newClassFieldDefinition(
+      Node name, FunctionNodeType initializer, bool isStatic
+#ifdef ENABLE_DECORATORS
+      ,
+      ListNodeType decorators, ClassMethodType accessorGetterNode,
+      ClassMethodType accessorSetterNode
+#endif
+  ) {
+    MOZ_ASSERT(isUsableAsObjectPropertyName(name));
+
+    return newResult<ClassField>(name, initializer, isStatic
+#if ENABLE_DECORATORS
+                                 ,
+                                 decorators, accessorGetterNode,
+                                 accessorSetterNode
+#endif
+    );
+  }
+
+  [[nodiscard]] StaticClassBlockResult newStaticClassBlock(
+      FunctionNodeType block) {
+    return newResult<StaticClassBlock>(block);
+  }
+
+  [[nodiscard]] bool addClassMemberDefinition(ListNodeType memberList,
+                                              Node member) {
+    MOZ_ASSERT(memberList->isKind(ParseNodeKind::ClassMemberList));
+    // Constructors can be surrounded by LexicalScopes.
+    MOZ_ASSERT(member->isKind(ParseNodeKind::DefaultConstructor) ||
+               member->isKind(ParseNodeKind::ClassMethod) ||
+               member->isKind(ParseNodeKind::ClassField) ||
+               member->isKind(ParseNodeKind::StaticClassBlock) ||
+               (member->isKind(ParseNodeKind::LexicalScope) &&
+                member->as<LexicalScopeNode>().scopeBody()->is<ClassMethod>()));
+
+    addList(/* list = */ memberList, /* kid = */ member);
+    return true;
+  }
+
+  UnaryNodeResult newInitialYieldExpression(uint32_t begin, Node gen) {
+    TokenPos pos(begin, begin + 1);
+    return newResult<UnaryNode>(ParseNodeKind::InitialYield, pos, gen);
+  }
+
+  UnaryNodeResult newYieldExpression(uint32_t begin, Node value) {
+    TokenPos pos(begin, value ? value->pn_pos.end : begin + 1);
+    return newResult<UnaryNode>(ParseNodeKind::YieldExpr, pos, value);
+  }
+
+  UnaryNodeResult newYieldStarExpression(uint32_t begin, Node value) {
+    TokenPos pos(begin, value->pn_pos.end);
+    return newResult<UnaryNode>(ParseNodeKind::YieldStarExpr, pos, value);
+  }
+
+  UnaryNodeResult newAwaitExpression(uint32_t begin, Node value) {
+    TokenPos pos(begin, value ? value->pn_pos.end : begin + 1);
+    return newResult<UnaryNode>(ParseNodeKind::AwaitExpr, pos, value);
+  }
+
+  UnaryNodeResult newOptionalChain(uint32_t begin, Node value) {
+    TokenPos pos(begin, value->pn_pos.end);
+    return newResult<UnaryNode>(ParseNodeKind::OptionalChain, pos, value);
+  }
+
+  // Statements
+
+  ListNodeResult newStatementList(const TokenPos& pos) {
+    return newResult<ListNode>(ParseNodeKind::StatementList, pos);
+  }
+
+  [[nodiscard]] bool isFunctionStmt(Node stmt) {
+    while (stmt->isKind(ParseNodeKind::LabelStmt)) {
+      stmt = stmt->as<LabeledStatement>().statement();
+    }
+    return stmt->is<FunctionNode>();
+  }
+
+  void addStatementToList(ListNodeType list, Node stmt) {
+    MOZ_ASSERT(list->isKind(ParseNodeKind::StatementList));
+
+    addList(/* list = */ list, /* kid = */ stmt);
+
+    if (isFunctionStmt(stmt)) {
+      // Notify the emitter that the block contains body-level function
+      // definitions that should be processed before the rest of nodes.
+      list->setHasTopLevelFunctionDeclarations();
+    }
+  }
+
+  void setListEndPosition(ListNodeType list, const TokenPos& pos) {
+    MOZ_ASSERT(list->isKind(ParseNodeKind::StatementList));
+    list->pn_pos.end = pos.end;
+  }
+
+  void addCaseStatementToList(ListNodeType list, CaseClauseType caseClause) {
+    MOZ_ASSERT(list->isKind(ParseNodeKind::StatementList));
+
+    addList(/* list = */ list, /* kid = */ caseClause);
+
+    if (caseClause->statementList()->hasTopLevelFunctionDeclarations()) {
+      list->setHasTopLevelFunctionDeclarations();
+    }
+  }
+
+  [[nodiscard]] bool prependInitialYield(ListNodeType stmtList, Node genName) {
+    MOZ_ASSERT(stmtList->isKind(ParseNodeKind::StatementList));
+
+    TokenPos yieldPos(stmtList->pn_pos.begin, stmtList->pn_pos.begin + 1);
+    NullaryNode* makeGen;
+    MOZ_TRY_VAR_OR_RETURN(
+        makeGen, newResult<NullaryNode>(ParseNodeKind::Generator, yieldPos),
+        false);
+
+    ParseNode* genInit;
+    MOZ_TRY_VAR_OR_RETURN(
+        genInit,
+        newAssignment(ParseNodeKind::AssignExpr, /* lhs = */ genName,
+                      /* rhs = */ makeGen),
+        false);
+
+    UnaryNode* initialYield;
+    MOZ_TRY_VAR_OR_RETURN(initialYield,
+                          newInitialYieldExpression(yieldPos.begin, genInit),
+                          false);
+
+    stmtList->prepend(initialYield);
+    return true;
+  }
+
+  BinaryNodeResult newSetThis(Node thisName, Node value) {
+    return newBinary(ParseNodeKind::SetThis, thisName, value);
+  }
+
+  NullaryNodeResult newEmptyStatement(const TokenPos& pos) {
+    return newResult<NullaryNode>(ParseNodeKind::EmptyStmt, pos);
+  }
+
+  BinaryNodeResult newImportAttribute(Node keyNode, Node valueNode) {
+    return newBinary(ParseNodeKind::ImportAttribute, keyNode, valueNode);
+  }
+
+  BinaryNodeResult newModuleRequest(Node moduleSpec, Node importAttributeList,
+                                    const TokenPos& pos) {
+    return newResult<BinaryNode>(ParseNodeKind::ImportModuleRequest, pos,
+                                 moduleSpec, importAttributeList);
+  }
+
+  BinaryNodeResult newImportDeclaration(Node importSpecSet, Node moduleRequest,
+                                        const TokenPos& pos) {
+    return newResult<BinaryNode>(ParseNodeKind::ImportDecl, pos, importSpecSet,
+                                 moduleRequest);
+  }
+
+  BinaryNodeResult newImportSpec(Node importNameNode, Node bindingName) {
+    return newBinary(ParseNodeKind::ImportSpec, importNameNode, bindingName);
+  }
+
+  UnaryNodeResult newImportNamespaceSpec(uint32_t begin, Node bindingName) {
+    return newUnary(ParseNodeKind::ImportNamespaceSpec, begin, bindingName);
+  }
+
+  UnaryNodeResult newExportDeclaration(Node kid, const TokenPos& pos) {
+    return newResult<UnaryNode>(ParseNodeKind::ExportStmt, pos, kid);
+  }
+
+  BinaryNodeResult newExportFromDeclaration(uint32_t begin, Node exportSpecSet,
+                                            Node moduleRequest) {
+    BinaryNode* decl;
+    MOZ_TRY_VAR(decl, newResult<BinaryNode>(ParseNodeKind::ExportFromStmt,
+                                            exportSpecSet, moduleRequest));
+    decl->pn_pos.begin = begin;
+    return decl;
+  }
+
+  BinaryNodeResult newExportDefaultDeclaration(Node kid, Node maybeBinding,
+                                               const TokenPos& pos) {
+    if (maybeBinding) {
+      MOZ_ASSERT(maybeBinding->isKind(ParseNodeKind::Name));
+      MOZ_ASSERT(!maybeBinding->isInParens());
+
+      checkAndSetIsDirectRHSAnonFunction(kid);
+    }
+
+    return newResult<BinaryNode>(ParseNodeKind::ExportDefaultStmt, pos, kid,
+                                 maybeBinding);
+  }
+
+  BinaryNodeResult newExportSpec(Node bindingName, Node exportName) {
+    return newBinary(ParseNodeKind::ExportSpec, bindingName, exportName);
+  }
+
+  UnaryNodeResult newExportNamespaceSpec(uint32_t begin, Node exportName) {
+    return newUnary(ParseNodeKind::ExportNamespaceSpec, begin, exportName);
+  }
+
+  NullaryNodeResult newExportBatchSpec(const TokenPos& pos) {
+    return newResult<NullaryNode>(ParseNodeKind::ExportBatchSpecStmt, pos);
+  }
+
+  BinaryNodeResult newImportMeta(NullaryNodeType importHolder,
+                                 NullaryNodeType metaHolder) {
+    return newResult<BinaryNode>(ParseNodeKind::ImportMetaExpr, importHolder,
+                                 metaHolder);
+  }
+
+  BinaryNodeResult newCallImport(NullaryNodeType importHolder, Node singleArg) {
+    return newResult<BinaryNode>(ParseNodeKind::CallImportExpr, importHolder,
+                                 singleArg);
+  }
+
+  BinaryNodeResult newCallImportSpec(Node specifierArg, Node optionalArg) {
+    return newResult<BinaryNode>(ParseNodeKind::CallImportSpec, specifierArg,
+                                 optionalArg);
+  }
+
+  UnaryNodeResult newExprStatement(Node expr, uint32_t end) {
+    MOZ_ASSERT(expr->pn_pos.end <= end);
+    return newResult<UnaryNode>(ParseNodeKind::ExpressionStmt,
+                                TokenPos(expr->pn_pos.begin, end), expr);
+  }
+
+  TernaryNodeResult newIfStatement(uint32_t begin, Node cond, Node thenBranch,
+                                   Node elseBranch) {
+    TernaryNode* node;
+    MOZ_TRY_VAR(node, newResult<TernaryNode>(ParseNodeKind::IfStmt, cond,
+                                             thenBranch, elseBranch));
+    node->pn_pos.begin = begin;
+    return node;
+  }
+
+  BinaryNodeResult newDoWhileStatement(Node body, Node cond,
+                                       const TokenPos& pos) {
+    return newResult<BinaryNode>(ParseNodeKind::DoWhileStmt, pos, body, cond);
+  }
+
+  BinaryNodeResult newWhileStatement(uint32_t begin, Node cond, Node body) {
+    TokenPos pos(begin, body->pn_pos.end);
+    return newResult<BinaryNode>(ParseNodeKind::WhileStmt, pos, cond, body);
+  }
+
+  ForNodeResult newForStatement(uint32_t begin, TernaryNodeType forHead,
+                                Node body, unsigned iflags) {
+    return newResult<ForNode>(TokenPos(begin, body->pn_pos.end), forHead, body,
+                              iflags);
+  }
+
+  TernaryNodeResult newForHead(Node init, Node test, Node update,
+                               const TokenPos& pos) {
+    return newResult<TernaryNode>(ParseNodeKind::ForHead, init, test, update,
+                                  pos);
+  }
+
+  TernaryNodeResult newForInOrOfHead(ParseNodeKind kind, Node target,
+                                     Node iteratedExpr, const TokenPos& pos) {
+    MOZ_ASSERT(kind == ParseNodeKind::ForIn || kind == ParseNodeKind::ForOf);
+    return newResult<TernaryNode>(kind, target, nullptr, iteratedExpr, pos);
+  }
+
+  SwitchStatementResult newSwitchStatement(
+      uint32_t begin, Node discriminant,
+      LexicalScopeNodeType lexicalForCaseList, bool hasDefault) {
+    return newResult<SwitchStatement>(begin, discriminant, lexicalForCaseList,
+                                      hasDefault);
+  }
+
+  CaseClauseResult newCaseOrDefault(uint32_t begin, Node expr, Node body) {
+    return newResult<CaseClause>(expr, body, begin);
+  }
+
+  ContinueStatementResult newContinueStatement(TaggedParserAtomIndex label,
+                                               const TokenPos& pos) {
+    return newResult<ContinueStatement>(label, pos);
+  }
+
+  BreakStatementResult newBreakStatement(TaggedParserAtomIndex label,
+                                         const TokenPos& pos) {
+    return newResult<BreakStatement>(label, pos);
+  }
+
+  UnaryNodeResult newReturnStatement(Node expr, const TokenPos& pos) {
+    MOZ_ASSERT_IF(expr, pos.encloses(expr->pn_pos));
+    return newResult<UnaryNode>(ParseNodeKind::ReturnStmt, pos, expr);
+  }
+
+  UnaryNodeResult newExpressionBody(Node expr) {
+    return newResult<UnaryNode>(ParseNodeKind::ReturnStmt, expr->pn_pos, expr);
+  }
+
+  BinaryNodeResult newWithStatement(uint32_t begin, Node expr, Node body) {
+    return newResult<BinaryNode>(ParseNodeKind::WithStmt,
+                                 TokenPos(begin, body->pn_pos.end), expr, body);
+  }
+
+  LabeledStatementResult newLabeledStatement(TaggedParserAtomIndex label,
+                                             Node stmt, uint32_t begin) {
+    return newResult<LabeledStatement>(label, stmt, begin);
+  }
+
+  UnaryNodeResult newThrowStatement(Node expr, const TokenPos& pos) {
+    MOZ_ASSERT(pos.encloses(expr->pn_pos));
+    return newResult<UnaryNode>(ParseNodeKind::ThrowStmt, pos, expr);
+  }
+
+  TernaryNodeResult newTryStatement(uint32_t begin, Node body,
+                                    LexicalScopeNodeType catchScope,
+                                    Node finallyBlock) {
+    return newResult<TryNode>(begin, body, catchScope, finallyBlock);
+  }
+
+  DebuggerStatementResult newDebuggerStatement(const TokenPos& pos) {
+    return newResult<DebuggerStatement>(pos);
+  }
+
+  NameNodeResult newPropertyName(TaggedParserAtomIndex name,
+                                 const TokenPos& pos) {
+    return newResult<NameNode>(ParseNodeKind::PropertyNameExpr, name, pos);
+  }
+
+  PropertyAccessResult newPropertyAccess(Node expr, NameNodeType key) {
+    return newResult<PropertyAccess>(expr, key, expr->pn_pos.begin,
+                                     key->pn_pos.end);
+  }
+
+  PropertyByValueResult newPropertyByValue(Node lhs, Node index, uint32_t end) {
+    return newResult<PropertyByValue>(lhs, index, lhs->pn_pos.begin, end);
+  }
+
+  OptionalPropertyAccessResult newOptionalPropertyAccess(Node expr,
+                                                         NameNodeType key) {
+    return newResult<OptionalPropertyAccess>(expr, key, expr->pn_pos.begin,
+                                             key->pn_pos.end);
+  }
+
+  OptionalPropertyByValueResult newOptionalPropertyByValue(Node lhs, Node index,
+                                                           uint32_t end) {
+    return newResult<OptionalPropertyByValue>(lhs, index, lhs->pn_pos.begin,
+                                              end);
+  }
+
+  PrivateMemberAccessResult newPrivateMemberAccess(Node lhs,
+                                                   NameNodeType privateName,
+                                                   uint32_t end) {
+    return newResult<PrivateMemberAccess>(lhs, privateName, lhs->pn_pos.begin,
+                                          end);
+  }
+
+  OptionalPrivateMemberAccessResult newOptionalPrivateMemberAccess(
+      Node lhs, NameNodeType privateName, uint32_t end) {
+    return newResult<OptionalPrivateMemberAccess>(lhs, privateName,
+                                                  lhs->pn_pos.begin, end);
+  }
+
+  bool setupCatchScope(LexicalScopeNodeType lexicalScope, Node catchName,
+                       Node catchBody) {
+    BinaryNode* catchClause;
+    if (catchName) {
+      MOZ_TRY_VAR_OR_RETURN(
+          catchClause,
+          newResult<BinaryNode>(ParseNodeKind::Catch, catchName, catchBody),
+          false);
+    } else {
+      MOZ_TRY_VAR_OR_RETURN(
+          catchClause,
+          newResult<BinaryNode>(ParseNodeKind::Catch, catchBody->pn_pos,
+                                catchName, catchBody),
+          false);
+    }
+    lexicalScope->setScopeBody(catchClause);
+    return true;
+  }
+
+  [[nodiscard]] inline bool setLastFunctionFormalParameterDefault(
+      FunctionNodeType funNode, Node defaultValue);
+
+  void checkAndSetIsDirectRHSAnonFunction(Node pn) {
+    if (IsAnonymousFunctionDefinition(pn)) {
+      pn->setDirectRHSAnonFunction(true);
+    }
+  }
+
+  ParamsBodyNodeResult newParamsBody(const TokenPos& pos) {
+    return newResult<ParamsBodyNode>(pos);
+  }
+
+  FunctionNodeResult newFunction(FunctionSyntaxKind syntaxKind,
+                                 const TokenPos& pos) {
+    return newResult<FunctionNode>(syntaxKind, pos);
+  }
+
+  BinaryNodeResult newObjectMethodOrPropertyDefinition(Node key, Node value,
+                                                       AccessorType atype) {
+    MOZ_ASSERT(isUsableAsObjectPropertyName(key));
+
+    return newResult<PropertyDefinition>(key, value, atype);
+  }
+
+  void setFunctionFormalParametersAndBody(FunctionNodeType funNode,
+                                          ParamsBodyNodeType paramsBody) {
+    funNode->setBody(paramsBody);
+  }
+  void setFunctionBox(FunctionNodeType funNode, FunctionBox* funbox) {
+    funNode->setFunbox(funbox);
+    funbox->functionNode = funNode;
+  }
+  void addFunctionFormalParameter(FunctionNodeType funNode, Node argpn) {
+    addList(/* list = */ funNode->body(), /* kid = */ argpn);
+  }
+  void setFunctionBody(FunctionNodeType funNode, LexicalScopeNodeType body) {
+    addList(/* list = */ funNode->body(), /* kid = */ body);
+  }
+
+  ModuleNodeResult newModule(const TokenPos& pos) {
+    return newResult<ModuleNode>(pos);
+  }
+
+  LexicalScopeNodeResult newLexicalScope(LexicalScope::ParserData* bindings,
+                                         Node body,
+                                         ScopeKind kind = ScopeKind::Lexical) {
+    return newResult<LexicalScopeNode>(bindings, body, kind);
+  }
+
+  ClassBodyScopeNodeResult newClassBodyScope(
+      ClassBodyScope::ParserData* bindings, ListNodeType body) {
+    return newResult<ClassBodyScopeNode>(bindings, body);
+  }
+
+  CallNodeResult newNewExpression(uint32_t begin, Node ctor, ListNodeType args,
+                                  bool isSpread) {
+    return newResult<CallNode>(ParseNodeKind::NewExpr,
+                               isSpread ? JSOp::SpreadNew : JSOp::New,
+                               TokenPos(begin, args->pn_pos.end), ctor, args);
+  }
+
+  AssignmentNodeResult newAssignment(ParseNodeKind kind, Node lhs, Node rhs) {
+    if ((kind == ParseNodeKind::AssignExpr ||
+         kind == ParseNodeKind::CoalesceAssignExpr ||
+         kind == ParseNodeKind::OrAssignExpr ||
+         kind == ParseNodeKind::AndAssignExpr) &&
+        lhs->isKind(ParseNodeKind::Name) && !lhs->isInParens()) {
+      checkAndSetIsDirectRHSAnonFunction(rhs);
+    }
+
+    return newResult<AssignmentNode>(kind, lhs, rhs);
+  }
+
+  BinaryNodeResult newInitExpr(Node lhs, Node rhs) {
+    TokenPos pos(lhs->pn_pos.begin, rhs->pn_pos.end);
+    return newResult<BinaryNode>(ParseNodeKind::InitExpr, pos, lhs, rhs);
+  }
+
+  bool isUnparenthesizedAssignment(Node node) {
+    if ((node->isKind(ParseNodeKind::AssignExpr)) && !node->isInParens()) {
+      return true;
+    }
+
+    return false;
+  }
+
+  bool isUnparenthesizedUnaryExpression(Node node) {
+    if (!node->isInParens()) {
+      ParseNodeKind kind = node->getKind();
+      return kind == ParseNodeKind::VoidExpr ||
+             kind == ParseNodeKind::NotExpr ||
+             kind == ParseNodeKind::BitNotExpr ||
+             kind == ParseNodeKind::PosExpr || kind == ParseNodeKind::NegExpr ||
+             kind == ParseNodeKind::AwaitExpr || IsTypeofKind(kind) ||
+             IsDeleteKind(kind);
+    }
+    return false;
+  }
+
+  bool isReturnStatement(Node node) {
+    return node->isKind(ParseNodeKind::ReturnStmt);
+  }
+
+  bool isStatementPermittedAfterReturnStatement(Node node) {
+    ParseNodeKind kind = node->getKind();
+    return kind == ParseNodeKind::Function || kind == ParseNodeKind::VarStmt ||
+           kind == ParseNodeKind::BreakStmt ||
+           kind == ParseNodeKind::ThrowStmt || kind == ParseNodeKind::EmptyStmt;
+  }
+
+  bool isSuperBase(Node node) { return node->isKind(ParseNodeKind::SuperBase); }
+
+  bool isUsableAsObjectPropertyName(Node node) {
+    return node->isKind(ParseNodeKind::NumberExpr) ||
+           node->isKind(ParseNodeKind::BigIntExpr) ||
+           node->isKind(ParseNodeKind::ObjectPropertyName) ||
+           node->isKind(ParseNodeKind::StringExpr) ||
+           node->isKind(ParseNodeKind::ComputedName) ||
+           node->isKind(ParseNodeKind::PrivateName);
+  }
+
+  AssignmentNodeResult finishInitializerAssignment(NameNodeType nameNode,
+                                                   Node init) {
+    MOZ_ASSERT(nameNode->isKind(ParseNodeKind::Name));
+    MOZ_ASSERT(!nameNode->isInParens());
+
+    checkAndSetIsDirectRHSAnonFunction(init);
+
+    return newAssignment(ParseNodeKind::AssignExpr, nameNode, init);
+  }
+
+  void setBeginPosition(Node pn, Node oth) {
+    setBeginPosition(pn, oth->pn_pos.begin);
+  }
+  void setBeginPosition(Node pn, uint32_t begin) {
+    pn->pn_pos.begin = begin;
+    MOZ_ASSERT(pn->pn_pos.begin <= pn->pn_pos.end);
+  }
+
+  void setEndPosition(Node pn, Node oth) {
+    setEndPosition(pn, oth->pn_pos.end);
+  }
+  void setEndPosition(Node pn, uint32_t end) {
+    pn->pn_pos.end = end;
+    MOZ_ASSERT(pn->pn_pos.begin <= pn->pn_pos.end);
+  }
+
+  uint32_t getFunctionNameOffset(Node func, TokenStreamAnyChars& ts) {
+    return func->pn_pos.begin;
+  }
+
+  ListNodeResult newList(ParseNodeKind kind, const TokenPos& pos) {
+    auto list = newResult<ListNode>(kind, pos);
+    MOZ_ASSERT_IF(list.isOk(), !list.unwrap()->is<DeclarationListNode>());
+    MOZ_ASSERT_IF(list.isOk(), !list.unwrap()->is<ParamsBodyNode>());
+    return list;
+  }
+
+  ListNodeResult newList(ParseNodeKind kind, Node kid) {
+    auto list = newResult<ListNode>(kind, kid);
+    MOZ_ASSERT_IF(list.isOk(), !list.unwrap()->is<DeclarationListNode>());
+    MOZ_ASSERT_IF(list.isOk(), !list.unwrap()->is<ParamsBodyNode>());
+    return list;
+  }
+
+  DeclarationListNodeResult newDeclarationList(ParseNodeKind kind,
+                                               const TokenPos& pos) {
+    return newResult<DeclarationListNode>(kind, pos);
+  }
+
+  ListNodeResult newCommaExpressionList(Node kid) {
+    return newResult<ListNode>(ParseNodeKind::CommaExpr, kid);
+  }
+
+  void addList(ListNodeType list, Node kid) { list->append(kid); }
+
+  void setListHasNonConstInitializer(ListNodeType literal) {
+    literal->setHasNonConstInitializer();
+  }
+
+  // NOTE: This is infallible.
+  template <typename NodeType>
+  [[nodiscard]] NodeType parenthesize(NodeType node) {
+    node->setInParens(true);
+    return node;
+  }
+
+  // NOTE: This is infallible.
+  template <typename NodeType>
+  [[nodiscard]] NodeType setLikelyIIFE(NodeType node) {
+    return parenthesize(node);
+  }
+
+  bool isName(Node node) { return node->isKind(ParseNodeKind::Name); }
+
+  bool isArgumentsName(Node node) {
+    return node->isKind(ParseNodeKind::Name) &&
+           node->as<NameNode>().atom() ==
+               TaggedParserAtomIndex::WellKnown::arguments();
+  }
+
+  bool isEvalName(Node node) {
+    return node->isKind(ParseNodeKind::Name) &&
+           node->as<NameNode>().atom() ==
+               TaggedParserAtomIndex::WellKnown::eval();
+  }
+
+  bool isAsyncKeyword(Node node) {
+    return node->isKind(ParseNodeKind::Name) &&
+           node->pn_pos.begin + strlen("async") == node->pn_pos.end &&
+           node->as<NameNode>().atom() ==
+               TaggedParserAtomIndex::WellKnown::async();
+  }
+
+  bool isPrivateName(Node node) {
+    return node->isKind(ParseNodeKind::PrivateName);
+  }
+
+  bool isPrivateMemberAccess(Node node) {
+    if (node->isKind(ParseNodeKind::OptionalChain)) {
+      return isPrivateMemberAccess(node->as<UnaryNode>().kid());
+    }
+    return node->is<PrivateMemberAccessBase>();
+  }
+
+  TaggedParserAtomIndex maybeDottedProperty(Node pn) {
+    return pn->is<PropertyAccessBase>() ? pn->as<PropertyAccessBase>().name()
+                                        : TaggedParserAtomIndex::null();
+  }
+  TaggedParserAtomIndex isStringExprStatement(Node pn, TokenPos* pos) {
+    if (pn->is<UnaryNode>()) {
+      UnaryNode* unary = &pn->as<UnaryNode>();
+      if (auto atom = unary->isStringExprStatement()) {
+        *pos = unary->kid()->pn_pos;
+        return atom;
+      }
+    }
+    return TaggedParserAtomIndex::null();
+  }
+
+  bool reuseLazyInnerFunctions() { return reuseGCThings; }
+  bool reuseClosedOverBindings() { return reuseGCThings; }
+  bool reuseRegexpSyntaxParse() { return reuseGCThings; }
+  void nextLazyInnerFunction() { lazyInnerFunctionIndex++; }
+  TaggedParserAtomIndex nextLazyClosedOverBinding() {
+    // Trailing nullptrs were elided in PerHandlerParser::finishFunction().
+    auto closedOverBindings = previousParseCache_.closedOverBindings();
+    if (lazyClosedOverBindingIndex >= closedOverBindings.Length()) {
+      return TaggedParserAtomIndex::null();
+    }
+
+    return closedOverBindings[lazyClosedOverBindingIndex++];
+  }
+  const ScriptStencil& cachedScriptData() const {
+    // lazyInnerFunctionIndex is incremented with nextLazyInnferFunction before
+    // reading the content, thus we need -1 to access the element that we just
+    // skipped.
+    return previousParseCache_.scriptData(lazyInnerFunctionIndex - 1);
+  }
+  const ScriptStencilExtra& cachedScriptExtra() const {
+    // lazyInnerFunctionIndex is incremented with nextLazyInnferFunction before
+    // reading the content, thus we need -1 to access the element that we just
+    // skipped.
+    return previousParseCache_.scriptExtra(lazyInnerFunctionIndex - 1);
+  }
+
+  void setPrivateNameKind(Node node, PrivateNameKind kind) {
+    MOZ_ASSERT(node->is<NameNode>());
+    node->as<NameNode>().setPrivateNameKind(kind);
+  }
+};
+
+inline bool FullParseHandler::setLastFunctionFormalParameterDefault(
+    FunctionNodeType funNode, Node defaultValue) {
+  ParamsBodyNode* body = funNode->body();
+  ParseNode* arg = body->last();
+  ParseNode* pn;
+  MOZ_TRY_VAR_OR_RETURN(
+      pn, newAssignment(ParseNodeKind::AssignExpr, arg, defaultValue), false);
+
+  body->replaceLast(pn);
+  return true;
+}
+
+}  // namespace frontend
+}  // namespace js
+
+#endif /* frontend_FullParseHandler_h */