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diff --git a/node_modules/sucrase/dist/esm/parser/traverser/expression.js b/node_modules/sucrase/dist/esm/parser/traverser/expression.js
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@@ -0,0 +1,1022 @@
+/* eslint max-len: 0 */
+
+// A recursive descent parser operates by defining functions for all
+// syntactic elements, and recursively calling those, each function
+// advancing the input stream and returning an AST node. Precedence
+// of constructs (for example, the fact that `!x[1]` means `!(x[1])`
+// instead of `(!x)[1]` is handled by the fact that the parser
+// function that parses unary prefix operators is called first, and
+// in turn calls the function that parses `[]` subscripts — that
+// way, it'll receive the node for `x[1]` already parsed, and wraps
+// *that* in the unary operator node.
+//
+// Acorn uses an [operator precedence parser][opp] to handle binary
+// operator precedence, because it is much more compact than using
+// the technique outlined above, which uses different, nesting
+// functions to specify precedence, for all of the ten binary
+// precedence levels that JavaScript defines.
+//
+// [opp]: http://en.wikipedia.org/wiki/Operator-precedence_parser
+
+import {
+  flowParseArrow,
+  flowParseFunctionBodyAndFinish,
+  flowParseMaybeAssign,
+  flowParseSubscript,
+  flowParseSubscripts,
+  flowParseVariance,
+  flowStartParseAsyncArrowFromCallExpression,
+  flowStartParseNewArguments,
+  flowStartParseObjPropValue,
+} from "../plugins/flow";
+import {jsxParseElement} from "../plugins/jsx/index";
+import {typedParseConditional, typedParseParenItem} from "../plugins/types";
+import {
+  tsParseArrow,
+  tsParseFunctionBodyAndFinish,
+  tsParseMaybeAssign,
+  tsParseSubscript,
+  tsParseType,
+  tsParseTypeAssertion,
+  tsStartParseAsyncArrowFromCallExpression,
+  tsStartParseObjPropValue,
+} from "../plugins/typescript";
+import {
+  eat,
+  IdentifierRole,
+  lookaheadCharCode,
+  lookaheadType,
+  match,
+  next,
+  nextTemplateToken,
+  popTypeContext,
+  pushTypeContext,
+  rescan_gt,
+  retokenizeSlashAsRegex,
+} from "../tokenizer/index";
+import {ContextualKeyword} from "../tokenizer/keywords";
+import {Scope} from "../tokenizer/state";
+import {TokenType, TokenType as tt} from "../tokenizer/types";
+import {charCodes} from "../util/charcodes";
+import {IS_IDENTIFIER_START} from "../util/identifier";
+import {getNextContextId, isFlowEnabled, isJSXEnabled, isTypeScriptEnabled, state} from "./base";
+import {
+  markPriorBindingIdentifier,
+  parseBindingIdentifier,
+  parseMaybeDefault,
+  parseRest,
+  parseSpread,
+} from "./lval";
+import {
+  parseBlock,
+  parseBlockBody,
+  parseClass,
+  parseDecorators,
+  parseFunction,
+  parseFunctionParams,
+} from "./statement";
+import {
+  canInsertSemicolon,
+  eatContextual,
+  expect,
+  expectContextual,
+  hasFollowingLineBreak,
+  hasPrecedingLineBreak,
+  isContextual,
+  unexpected,
+} from "./util";
+
+export class StopState {
+  
+  constructor(stop) {
+    this.stop = stop;
+  }
+}
+
+// ### Expression parsing
+
+// These nest, from the most general expression type at the top to
+// 'atomic', nondivisible expression types at the bottom. Most of
+// the functions will simply let the function (s) below them parse,
+// and, *if* the syntactic construct they handle is present, wrap
+// the AST node that the inner parser gave them in another node.
+export function parseExpression(noIn = false) {
+  parseMaybeAssign(noIn);
+  if (match(tt.comma)) {
+    while (eat(tt.comma)) {
+      parseMaybeAssign(noIn);
+    }
+  }
+}
+
+/**
+ * noIn is used when parsing a for loop so that we don't interpret a following "in" as the binary
+ * operatior.
+ * isWithinParens is used to indicate that we're parsing something that might be a comma expression
+ * or might be an arrow function or might be a Flow type assertion (which requires explicit parens).
+ * In these cases, we should allow : and ?: after the initial "left" part.
+ */
+export function parseMaybeAssign(noIn = false, isWithinParens = false) {
+  if (isTypeScriptEnabled) {
+    return tsParseMaybeAssign(noIn, isWithinParens);
+  } else if (isFlowEnabled) {
+    return flowParseMaybeAssign(noIn, isWithinParens);
+  } else {
+    return baseParseMaybeAssign(noIn, isWithinParens);
+  }
+}
+
+// Parse an assignment expression. This includes applications of
+// operators like `+=`.
+// Returns true if the expression was an arrow function.
+export function baseParseMaybeAssign(noIn, isWithinParens) {
+  if (match(tt._yield)) {
+    parseYield();
+    return false;
+  }
+
+  if (match(tt.parenL) || match(tt.name) || match(tt._yield)) {
+    state.potentialArrowAt = state.start;
+  }
+
+  const wasArrow = parseMaybeConditional(noIn);
+  if (isWithinParens) {
+    parseParenItem();
+  }
+  if (state.type & TokenType.IS_ASSIGN) {
+    next();
+    parseMaybeAssign(noIn);
+    return false;
+  }
+  return wasArrow;
+}
+
+// Parse a ternary conditional (`?:`) operator.
+// Returns true if the expression was an arrow function.
+function parseMaybeConditional(noIn) {
+  const wasArrow = parseExprOps(noIn);
+  if (wasArrow) {
+    return true;
+  }
+  parseConditional(noIn);
+  return false;
+}
+
+function parseConditional(noIn) {
+  if (isTypeScriptEnabled || isFlowEnabled) {
+    typedParseConditional(noIn);
+  } else {
+    baseParseConditional(noIn);
+  }
+}
+
+export function baseParseConditional(noIn) {
+  if (eat(tt.question)) {
+    parseMaybeAssign();
+    expect(tt.colon);
+    parseMaybeAssign(noIn);
+  }
+}
+
+// Start the precedence parser.
+// Returns true if this was an arrow function
+function parseExprOps(noIn) {
+  const startTokenIndex = state.tokens.length;
+  const wasArrow = parseMaybeUnary();
+  if (wasArrow) {
+    return true;
+  }
+  parseExprOp(startTokenIndex, -1, noIn);
+  return false;
+}
+
+// Parse binary operators with the operator precedence parsing
+// algorithm. `left` is the left-hand side of the operator.
+// `minPrec` provides context that allows the function to stop and
+// defer further parser to one of its callers when it encounters an
+// operator that has a lower precedence than the set it is parsing.
+function parseExprOp(startTokenIndex, minPrec, noIn) {
+  if (
+    isTypeScriptEnabled &&
+    (tt._in & TokenType.PRECEDENCE_MASK) > minPrec &&
+    !hasPrecedingLineBreak() &&
+    (eatContextual(ContextualKeyword._as) || eatContextual(ContextualKeyword._satisfies))
+  ) {
+    const oldIsType = pushTypeContext(1);
+    tsParseType();
+    popTypeContext(oldIsType);
+    rescan_gt();
+    parseExprOp(startTokenIndex, minPrec, noIn);
+    return;
+  }
+
+  const prec = state.type & TokenType.PRECEDENCE_MASK;
+  if (prec > 0 && (!noIn || !match(tt._in))) {
+    if (prec > minPrec) {
+      const op = state.type;
+      next();
+      if (op === tt.nullishCoalescing) {
+        state.tokens[state.tokens.length - 1].nullishStartIndex = startTokenIndex;
+      }
+
+      const rhsStartTokenIndex = state.tokens.length;
+      parseMaybeUnary();
+      // Extend the right operand of this operator if possible.
+      parseExprOp(rhsStartTokenIndex, op & TokenType.IS_RIGHT_ASSOCIATIVE ? prec - 1 : prec, noIn);
+      if (op === tt.nullishCoalescing) {
+        state.tokens[startTokenIndex].numNullishCoalesceStarts++;
+        state.tokens[state.tokens.length - 1].numNullishCoalesceEnds++;
+      }
+      // Continue with any future operator holding this expression as the left operand.
+      parseExprOp(startTokenIndex, minPrec, noIn);
+    }
+  }
+}
+
+// Parse unary operators, both prefix and postfix.
+// Returns true if this was an arrow function.
+export function parseMaybeUnary() {
+  if (isTypeScriptEnabled && !isJSXEnabled && eat(tt.lessThan)) {
+    tsParseTypeAssertion();
+    return false;
+  }
+  if (
+    isContextual(ContextualKeyword._module) &&
+    lookaheadCharCode() === charCodes.leftCurlyBrace &&
+    !hasFollowingLineBreak()
+  ) {
+    parseModuleExpression();
+    return false;
+  }
+  if (state.type & TokenType.IS_PREFIX) {
+    next();
+    parseMaybeUnary();
+    return false;
+  }
+
+  const wasArrow = parseExprSubscripts();
+  if (wasArrow) {
+    return true;
+  }
+  while (state.type & TokenType.IS_POSTFIX && !canInsertSemicolon()) {
+    // The tokenizer calls everything a preincrement, so make it a postincrement when
+    // we see it in that context.
+    if (state.type === tt.preIncDec) {
+      state.type = tt.postIncDec;
+    }
+    next();
+  }
+  return false;
+}
+
+// Parse call, dot, and `[]`-subscript expressions.
+// Returns true if this was an arrow function.
+export function parseExprSubscripts() {
+  const startTokenIndex = state.tokens.length;
+  const wasArrow = parseExprAtom();
+  if (wasArrow) {
+    return true;
+  }
+  parseSubscripts(startTokenIndex);
+  // If there was any optional chain operation, the start token would be marked
+  // as such, so also mark the end now.
+  if (state.tokens.length > startTokenIndex && state.tokens[startTokenIndex].isOptionalChainStart) {
+    state.tokens[state.tokens.length - 1].isOptionalChainEnd = true;
+  }
+  return false;
+}
+
+function parseSubscripts(startTokenIndex, noCalls = false) {
+  if (isFlowEnabled) {
+    flowParseSubscripts(startTokenIndex, noCalls);
+  } else {
+    baseParseSubscripts(startTokenIndex, noCalls);
+  }
+}
+
+export function baseParseSubscripts(startTokenIndex, noCalls = false) {
+  const stopState = new StopState(false);
+  do {
+    parseSubscript(startTokenIndex, noCalls, stopState);
+  } while (!stopState.stop && !state.error);
+}
+
+function parseSubscript(startTokenIndex, noCalls, stopState) {
+  if (isTypeScriptEnabled) {
+    tsParseSubscript(startTokenIndex, noCalls, stopState);
+  } else if (isFlowEnabled) {
+    flowParseSubscript(startTokenIndex, noCalls, stopState);
+  } else {
+    baseParseSubscript(startTokenIndex, noCalls, stopState);
+  }
+}
+
+/** Set 'state.stop = true' to indicate that we should stop parsing subscripts. */
+export function baseParseSubscript(
+  startTokenIndex,
+  noCalls,
+  stopState,
+) {
+  if (!noCalls && eat(tt.doubleColon)) {
+    parseNoCallExpr();
+    stopState.stop = true;
+    // Propagate startTokenIndex so that `a::b?.()` will keep `a` as the first token. We may want
+    // to revisit this in the future when fully supporting bind syntax.
+    parseSubscripts(startTokenIndex, noCalls);
+  } else if (match(tt.questionDot)) {
+    state.tokens[startTokenIndex].isOptionalChainStart = true;
+    if (noCalls && lookaheadType() === tt.parenL) {
+      stopState.stop = true;
+      return;
+    }
+    next();
+    state.tokens[state.tokens.length - 1].subscriptStartIndex = startTokenIndex;
+
+    if (eat(tt.bracketL)) {
+      parseExpression();
+      expect(tt.bracketR);
+    } else if (eat(tt.parenL)) {
+      parseCallExpressionArguments();
+    } else {
+      parseMaybePrivateName();
+    }
+  } else if (eat(tt.dot)) {
+    state.tokens[state.tokens.length - 1].subscriptStartIndex = startTokenIndex;
+    parseMaybePrivateName();
+  } else if (eat(tt.bracketL)) {
+    state.tokens[state.tokens.length - 1].subscriptStartIndex = startTokenIndex;
+    parseExpression();
+    expect(tt.bracketR);
+  } else if (!noCalls && match(tt.parenL)) {
+    if (atPossibleAsync()) {
+      // We see "async", but it's possible it's a usage of the name "async". Parse as if it's a
+      // function call, and if we see an arrow later, backtrack and re-parse as a parameter list.
+      const snapshot = state.snapshot();
+      const asyncStartTokenIndex = state.tokens.length;
+      next();
+      state.tokens[state.tokens.length - 1].subscriptStartIndex = startTokenIndex;
+
+      const callContextId = getNextContextId();
+
+      state.tokens[state.tokens.length - 1].contextId = callContextId;
+      parseCallExpressionArguments();
+      state.tokens[state.tokens.length - 1].contextId = callContextId;
+
+      if (shouldParseAsyncArrow()) {
+        // We hit an arrow, so backtrack and start again parsing function parameters.
+        state.restoreFromSnapshot(snapshot);
+        stopState.stop = true;
+        state.scopeDepth++;
+
+        parseFunctionParams();
+        parseAsyncArrowFromCallExpression(asyncStartTokenIndex);
+      }
+    } else {
+      next();
+      state.tokens[state.tokens.length - 1].subscriptStartIndex = startTokenIndex;
+      const callContextId = getNextContextId();
+      state.tokens[state.tokens.length - 1].contextId = callContextId;
+      parseCallExpressionArguments();
+      state.tokens[state.tokens.length - 1].contextId = callContextId;
+    }
+  } else if (match(tt.backQuote)) {
+    // Tagged template expression.
+    parseTemplate();
+  } else {
+    stopState.stop = true;
+  }
+}
+
+export function atPossibleAsync() {
+  // This was made less strict than the original version to avoid passing around nodes, but it
+  // should be safe to have rare false positives here.
+  return (
+    state.tokens[state.tokens.length - 1].contextualKeyword === ContextualKeyword._async &&
+    !canInsertSemicolon()
+  );
+}
+
+export function parseCallExpressionArguments() {
+  let first = true;
+  while (!eat(tt.parenR) && !state.error) {
+    if (first) {
+      first = false;
+    } else {
+      expect(tt.comma);
+      if (eat(tt.parenR)) {
+        break;
+      }
+    }
+
+    parseExprListItem(false);
+  }
+}
+
+function shouldParseAsyncArrow() {
+  return match(tt.colon) || match(tt.arrow);
+}
+
+function parseAsyncArrowFromCallExpression(startTokenIndex) {
+  if (isTypeScriptEnabled) {
+    tsStartParseAsyncArrowFromCallExpression();
+  } else if (isFlowEnabled) {
+    flowStartParseAsyncArrowFromCallExpression();
+  }
+  expect(tt.arrow);
+  parseArrowExpression(startTokenIndex);
+}
+
+// Parse a no-call expression (like argument of `new` or `::` operators).
+
+function parseNoCallExpr() {
+  const startTokenIndex = state.tokens.length;
+  parseExprAtom();
+  parseSubscripts(startTokenIndex, true);
+}
+
+// Parse an atomic expression — either a single token that is an
+// expression, an expression started by a keyword like `function` or
+// `new`, or an expression wrapped in punctuation like `()`, `[]`,
+// or `{}`.
+// Returns true if the parsed expression was an arrow function.
+export function parseExprAtom() {
+  if (eat(tt.modulo)) {
+    // V8 intrinsic expression. Just parse the identifier, and the function invocation is parsed
+    // naturally.
+    parseIdentifier();
+    return false;
+  }
+
+  if (match(tt.jsxText) || match(tt.jsxEmptyText)) {
+    parseLiteral();
+    return false;
+  } else if (match(tt.lessThan) && isJSXEnabled) {
+    state.type = tt.jsxTagStart;
+    jsxParseElement();
+    next();
+    return false;
+  }
+
+  const canBeArrow = state.potentialArrowAt === state.start;
+  switch (state.type) {
+    case tt.slash:
+    case tt.assign:
+      retokenizeSlashAsRegex();
+    // Fall through.
+
+    case tt._super:
+    case tt._this:
+    case tt.regexp:
+    case tt.num:
+    case tt.bigint:
+    case tt.decimal:
+    case tt.string:
+    case tt._null:
+    case tt._true:
+    case tt._false:
+      next();
+      return false;
+
+    case tt._import:
+      next();
+      if (match(tt.dot)) {
+        // import.meta
+        state.tokens[state.tokens.length - 1].type = tt.name;
+        next();
+        parseIdentifier();
+      }
+      return false;
+
+    case tt.name: {
+      const startTokenIndex = state.tokens.length;
+      const functionStart = state.start;
+      const contextualKeyword = state.contextualKeyword;
+      parseIdentifier();
+      if (contextualKeyword === ContextualKeyword._await) {
+        parseAwait();
+        return false;
+      } else if (
+        contextualKeyword === ContextualKeyword._async &&
+        match(tt._function) &&
+        !canInsertSemicolon()
+      ) {
+        next();
+        parseFunction(functionStart, false);
+        return false;
+      } else if (
+        canBeArrow &&
+        contextualKeyword === ContextualKeyword._async &&
+        !canInsertSemicolon() &&
+        match(tt.name)
+      ) {
+        state.scopeDepth++;
+        parseBindingIdentifier(false);
+        expect(tt.arrow);
+        // let foo = async bar => {};
+        parseArrowExpression(startTokenIndex);
+        return true;
+      } else if (match(tt._do) && !canInsertSemicolon()) {
+        next();
+        parseBlock();
+        return false;
+      }
+
+      if (canBeArrow && !canInsertSemicolon() && match(tt.arrow)) {
+        state.scopeDepth++;
+        markPriorBindingIdentifier(false);
+        expect(tt.arrow);
+        parseArrowExpression(startTokenIndex);
+        return true;
+      }
+
+      state.tokens[state.tokens.length - 1].identifierRole = IdentifierRole.Access;
+      return false;
+    }
+
+    case tt._do: {
+      next();
+      parseBlock();
+      return false;
+    }
+
+    case tt.parenL: {
+      const wasArrow = parseParenAndDistinguishExpression(canBeArrow);
+      return wasArrow;
+    }
+
+    case tt.bracketL:
+      next();
+      parseExprList(tt.bracketR, true);
+      return false;
+
+    case tt.braceL:
+      parseObj(false, false);
+      return false;
+
+    case tt._function:
+      parseFunctionExpression();
+      return false;
+
+    case tt.at:
+      parseDecorators();
+    // Fall through.
+
+    case tt._class:
+      parseClass(false);
+      return false;
+
+    case tt._new:
+      parseNew();
+      return false;
+
+    case tt.backQuote:
+      parseTemplate();
+      return false;
+
+    case tt.doubleColon: {
+      next();
+      parseNoCallExpr();
+      return false;
+    }
+
+    case tt.hash: {
+      const code = lookaheadCharCode();
+      if (IS_IDENTIFIER_START[code] || code === charCodes.backslash) {
+        parseMaybePrivateName();
+      } else {
+        next();
+      }
+      // Smart pipeline topic reference.
+      return false;
+    }
+
+    default:
+      unexpected();
+      return false;
+  }
+}
+
+function parseMaybePrivateName() {
+  eat(tt.hash);
+  parseIdentifier();
+}
+
+function parseFunctionExpression() {
+  const functionStart = state.start;
+  parseIdentifier();
+  if (eat(tt.dot)) {
+    // function.sent
+    parseIdentifier();
+  }
+  parseFunction(functionStart, false);
+}
+
+export function parseLiteral() {
+  next();
+}
+
+export function parseParenExpression() {
+  expect(tt.parenL);
+  parseExpression();
+  expect(tt.parenR);
+}
+
+// Returns true if this was an arrow expression.
+function parseParenAndDistinguishExpression(canBeArrow) {
+  // Assume this is a normal parenthesized expression, but if we see an arrow, we'll bail and
+  // start over as a parameter list.
+  const snapshot = state.snapshot();
+
+  const startTokenIndex = state.tokens.length;
+  expect(tt.parenL);
+
+  let first = true;
+
+  while (!match(tt.parenR) && !state.error) {
+    if (first) {
+      first = false;
+    } else {
+      expect(tt.comma);
+      if (match(tt.parenR)) {
+        break;
+      }
+    }
+
+    if (match(tt.ellipsis)) {
+      parseRest(false /* isBlockScope */);
+      parseParenItem();
+      break;
+    } else {
+      parseMaybeAssign(false, true);
+    }
+  }
+
+  expect(tt.parenR);
+
+  if (canBeArrow && shouldParseArrow()) {
+    const wasArrow = parseArrow();
+    if (wasArrow) {
+      // It was an arrow function this whole time, so start over and parse it as params so that we
+      // get proper token annotations.
+      state.restoreFromSnapshot(snapshot);
+      state.scopeDepth++;
+      // Don't specify a context ID because arrow functions don't need a context ID.
+      parseFunctionParams();
+      parseArrow();
+      parseArrowExpression(startTokenIndex);
+      if (state.error) {
+        // Nevermind! This must have been something that looks very much like an
+        // arrow function but where its "parameter list" isn't actually a valid
+        // parameter list. Force non-arrow parsing.
+        // See https://github.com/alangpierce/sucrase/issues/666 for an example.
+        state.restoreFromSnapshot(snapshot);
+        parseParenAndDistinguishExpression(false);
+        return false;
+      }
+      return true;
+    }
+  }
+
+  return false;
+}
+
+function shouldParseArrow() {
+  return match(tt.colon) || !canInsertSemicolon();
+}
+
+// Returns whether there was an arrow token.
+export function parseArrow() {
+  if (isTypeScriptEnabled) {
+    return tsParseArrow();
+  } else if (isFlowEnabled) {
+    return flowParseArrow();
+  } else {
+    return eat(tt.arrow);
+  }
+}
+
+function parseParenItem() {
+  if (isTypeScriptEnabled || isFlowEnabled) {
+    typedParseParenItem();
+  }
+}
+
+// New's precedence is slightly tricky. It must allow its argument to
+// be a `[]` or dot subscript expression, but not a call — at least,
+// not without wrapping it in parentheses. Thus, it uses the noCalls
+// argument to parseSubscripts to prevent it from consuming the
+// argument list.
+function parseNew() {
+  expect(tt._new);
+  if (eat(tt.dot)) {
+    // new.target
+    parseIdentifier();
+    return;
+  }
+  parseNewCallee();
+  if (isFlowEnabled) {
+    flowStartParseNewArguments();
+  }
+  if (eat(tt.parenL)) {
+    parseExprList(tt.parenR);
+  }
+}
+
+function parseNewCallee() {
+  parseNoCallExpr();
+  eat(tt.questionDot);
+}
+
+export function parseTemplate() {
+  // Finish `, read quasi
+  nextTemplateToken();
+  // Finish quasi, read ${
+  nextTemplateToken();
+  while (!match(tt.backQuote) && !state.error) {
+    expect(tt.dollarBraceL);
+    parseExpression();
+    // Finish }, read quasi
+    nextTemplateToken();
+    // Finish quasi, read either ${ or `
+    nextTemplateToken();
+  }
+  next();
+}
+
+// Parse an object literal or binding pattern.
+export function parseObj(isPattern, isBlockScope) {
+  // Attach a context ID to the object open and close brace and each object key.
+  const contextId = getNextContextId();
+  let first = true;
+
+  next();
+  state.tokens[state.tokens.length - 1].contextId = contextId;
+
+  while (!eat(tt.braceR) && !state.error) {
+    if (first) {
+      first = false;
+    } else {
+      expect(tt.comma);
+      if (eat(tt.braceR)) {
+        break;
+      }
+    }
+
+    let isGenerator = false;
+    if (match(tt.ellipsis)) {
+      const previousIndex = state.tokens.length;
+      parseSpread();
+      if (isPattern) {
+        // Mark role when the only thing being spread over is an identifier.
+        if (state.tokens.length === previousIndex + 2) {
+          markPriorBindingIdentifier(isBlockScope);
+        }
+        if (eat(tt.braceR)) {
+          break;
+        }
+      }
+      continue;
+    }
+
+    if (!isPattern) {
+      isGenerator = eat(tt.star);
+    }
+
+    if (!isPattern && isContextual(ContextualKeyword._async)) {
+      if (isGenerator) unexpected();
+
+      parseIdentifier();
+      if (
+        match(tt.colon) ||
+        match(tt.parenL) ||
+        match(tt.braceR) ||
+        match(tt.eq) ||
+        match(tt.comma)
+      ) {
+        // This is a key called "async" rather than an async function.
+      } else {
+        if (match(tt.star)) {
+          next();
+          isGenerator = true;
+        }
+        parsePropertyName(contextId);
+      }
+    } else {
+      parsePropertyName(contextId);
+    }
+
+    parseObjPropValue(isPattern, isBlockScope, contextId);
+  }
+
+  state.tokens[state.tokens.length - 1].contextId = contextId;
+}
+
+function isGetterOrSetterMethod(isPattern) {
+  // We go off of the next and don't bother checking if the node key is actually "get" or "set".
+  // This lets us avoid generating a node, and should only make the validation worse.
+  return (
+    !isPattern &&
+    (match(tt.string) || // get "string"() {}
+      match(tt.num) || // get 1() {}
+      match(tt.bracketL) || // get ["string"]() {}
+      match(tt.name) || // get foo() {}
+      !!(state.type & TokenType.IS_KEYWORD)) // get debugger() {}
+  );
+}
+
+// Returns true if this was a method.
+function parseObjectMethod(isPattern, objectContextId) {
+  // We don't need to worry about modifiers because object methods can't have optional bodies, so
+  // the start will never be used.
+  const functionStart = state.start;
+  if (match(tt.parenL)) {
+    if (isPattern) unexpected();
+    parseMethod(functionStart, /* isConstructor */ false);
+    return true;
+  }
+
+  if (isGetterOrSetterMethod(isPattern)) {
+    parsePropertyName(objectContextId);
+    parseMethod(functionStart, /* isConstructor */ false);
+    return true;
+  }
+  return false;
+}
+
+function parseObjectProperty(isPattern, isBlockScope) {
+  if (eat(tt.colon)) {
+    if (isPattern) {
+      parseMaybeDefault(isBlockScope);
+    } else {
+      parseMaybeAssign(false);
+    }
+    return;
+  }
+
+  // Since there's no colon, we assume this is an object shorthand.
+
+  // If we're in a destructuring, we've now discovered that the key was actually an assignee, so
+  // we need to tag it as a declaration with the appropriate scope. Otherwise, we might need to
+  // transform it on access, so mark it as a normal object shorthand.
+  let identifierRole;
+  if (isPattern) {
+    if (state.scopeDepth === 0) {
+      identifierRole = IdentifierRole.ObjectShorthandTopLevelDeclaration;
+    } else if (isBlockScope) {
+      identifierRole = IdentifierRole.ObjectShorthandBlockScopedDeclaration;
+    } else {
+      identifierRole = IdentifierRole.ObjectShorthandFunctionScopedDeclaration;
+    }
+  } else {
+    identifierRole = IdentifierRole.ObjectShorthand;
+  }
+  state.tokens[state.tokens.length - 1].identifierRole = identifierRole;
+
+  // Regardless of whether we know this to be a pattern or if we're in an ambiguous context, allow
+  // parsing as if there's a default value.
+  parseMaybeDefault(isBlockScope, true);
+}
+
+function parseObjPropValue(
+  isPattern,
+  isBlockScope,
+  objectContextId,
+) {
+  if (isTypeScriptEnabled) {
+    tsStartParseObjPropValue();
+  } else if (isFlowEnabled) {
+    flowStartParseObjPropValue();
+  }
+  const wasMethod = parseObjectMethod(isPattern, objectContextId);
+  if (!wasMethod) {
+    parseObjectProperty(isPattern, isBlockScope);
+  }
+}
+
+export function parsePropertyName(objectContextId) {
+  if (isFlowEnabled) {
+    flowParseVariance();
+  }
+  if (eat(tt.bracketL)) {
+    state.tokens[state.tokens.length - 1].contextId = objectContextId;
+    parseMaybeAssign();
+    expect(tt.bracketR);
+    state.tokens[state.tokens.length - 1].contextId = objectContextId;
+  } else {
+    if (match(tt.num) || match(tt.string) || match(tt.bigint) || match(tt.decimal)) {
+      parseExprAtom();
+    } else {
+      parseMaybePrivateName();
+    }
+
+    state.tokens[state.tokens.length - 1].identifierRole = IdentifierRole.ObjectKey;
+    state.tokens[state.tokens.length - 1].contextId = objectContextId;
+  }
+}
+
+// Parse object or class method.
+export function parseMethod(functionStart, isConstructor) {
+  const funcContextId = getNextContextId();
+
+  state.scopeDepth++;
+  const startTokenIndex = state.tokens.length;
+  const allowModifiers = isConstructor; // For TypeScript parameter properties
+  parseFunctionParams(allowModifiers, funcContextId);
+  parseFunctionBodyAndFinish(functionStart, funcContextId);
+  const endTokenIndex = state.tokens.length;
+  state.scopes.push(new Scope(startTokenIndex, endTokenIndex, true));
+  state.scopeDepth--;
+}
+
+// Parse arrow function expression.
+// If the parameters are provided, they will be converted to an
+// assignable list.
+export function parseArrowExpression(startTokenIndex) {
+  parseFunctionBody(true);
+  const endTokenIndex = state.tokens.length;
+  state.scopes.push(new Scope(startTokenIndex, endTokenIndex, true));
+  state.scopeDepth--;
+}
+
+export function parseFunctionBodyAndFinish(functionStart, funcContextId = 0) {
+  if (isTypeScriptEnabled) {
+    tsParseFunctionBodyAndFinish(functionStart, funcContextId);
+  } else if (isFlowEnabled) {
+    flowParseFunctionBodyAndFinish(funcContextId);
+  } else {
+    parseFunctionBody(false, funcContextId);
+  }
+}
+
+export function parseFunctionBody(allowExpression, funcContextId = 0) {
+  const isExpression = allowExpression && !match(tt.braceL);
+
+  if (isExpression) {
+    parseMaybeAssign();
+  } else {
+    parseBlock(true /* isFunctionScope */, funcContextId);
+  }
+}
+
+// Parses a comma-separated list of expressions, and returns them as
+// an array. `close` is the token type that ends the list, and
+// `allowEmpty` can be turned on to allow subsequent commas with
+// nothing in between them to be parsed as `null` (which is needed
+// for array literals).
+
+function parseExprList(close, allowEmpty = false) {
+  let first = true;
+  while (!eat(close) && !state.error) {
+    if (first) {
+      first = false;
+    } else {
+      expect(tt.comma);
+      if (eat(close)) break;
+    }
+    parseExprListItem(allowEmpty);
+  }
+}
+
+function parseExprListItem(allowEmpty) {
+  if (allowEmpty && match(tt.comma)) {
+    // Empty item; nothing more to parse for this item.
+  } else if (match(tt.ellipsis)) {
+    parseSpread();
+    parseParenItem();
+  } else if (match(tt.question)) {
+    // Partial function application proposal.
+    next();
+  } else {
+    parseMaybeAssign(false, true);
+  }
+}
+
+// Parse the next token as an identifier.
+export function parseIdentifier() {
+  next();
+  state.tokens[state.tokens.length - 1].type = tt.name;
+}
+
+// Parses await expression inside async function.
+function parseAwait() {
+  parseMaybeUnary();
+}
+
+// Parses yield expression inside generator.
+function parseYield() {
+  next();
+  if (!match(tt.semi) && !canInsertSemicolon()) {
+    eat(tt.star);
+    parseMaybeAssign();
+  }
+}
+
+// https://github.com/tc39/proposal-js-module-blocks
+function parseModuleExpression() {
+  expectContextual(ContextualKeyword._module);
+  expect(tt.braceL);
+  // For now, just call parseBlockBody to parse the block. In the future when we
+  // implement full support, we'll want to emit scopes and possibly other
+  // information.
+  parseBlockBody(tt.braceR);
+}