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1 files changed, 1332 insertions, 0 deletions

diff --git a/node_modules/sucrase/dist/esm/parser/traverser/statement.js b/node_modules/sucrase/dist/esm/parser/traverser/statement.js
new file mode 100644
index 0000000..34a6511
--- /dev/null
+++ b/node_modules/sucrase/dist/esm/parser/traverser/statement.js
@@ -0,0 +1,1332 @@
+/* eslint max-len: 0 */
+
+import {File} from "../index";
+import {
+  flowAfterParseClassSuper,
+  flowAfterParseVarHead,
+  flowParseExportDeclaration,
+  flowParseExportStar,
+  flowParseIdentifierStatement,
+  flowParseImportSpecifier,
+  flowParseTypeAnnotation,
+  flowParseTypeParameterDeclaration,
+  flowShouldDisallowExportDefaultSpecifier,
+  flowShouldParseExportDeclaration,
+  flowShouldParseExportStar,
+  flowStartParseFunctionParams,
+  flowStartParseImportSpecifiers,
+  flowTryParseExportDefaultExpression,
+  flowTryParseStatement,
+} from "../plugins/flow";
+import {
+  tsAfterParseClassSuper,
+  tsAfterParseVarHead,
+  tsIsDeclarationStart,
+  tsParseExportDeclaration,
+  tsParseExportSpecifier,
+  tsParseIdentifierStatement,
+  tsParseImportEqualsDeclaration,
+  tsParseImportSpecifier,
+  tsParseMaybeDecoratorArguments,
+  tsParseModifiers,
+  tsStartParseFunctionParams,
+  tsTryParseClassMemberWithIsStatic,
+  tsTryParseExport,
+  tsTryParseExportDefaultExpression,
+  tsTryParseStatementContent,
+  tsTryParseTypeAnnotation,
+  tsTryParseTypeParameters,
+} from "../plugins/typescript";
+import {
+  eat,
+  eatTypeToken,
+  IdentifierRole,
+  lookaheadType,
+  lookaheadTypeAndKeyword,
+  match,
+  next,
+  nextTokenStart,
+  nextTokenStartSince,
+  popTypeContext,
+  pushTypeContext,
+} from "../tokenizer";
+import {ContextualKeyword} from "../tokenizer/keywords";
+import {Scope} from "../tokenizer/state";
+import { TokenType as tt} from "../tokenizer/types";
+import {charCodes} from "../util/charcodes";
+import {getNextContextId, input, isFlowEnabled, isTypeScriptEnabled, state} from "./base";
+import {
+  parseCallExpressionArguments,
+  parseExprAtom,
+  parseExpression,
+  parseExprSubscripts,
+  parseFunctionBodyAndFinish,
+  parseIdentifier,
+  parseMaybeAssign,
+  parseMethod,
+  parseObj,
+  parseParenExpression,
+  parsePropertyName,
+} from "./expression";
+import {
+  parseBindingAtom,
+  parseBindingIdentifier,
+  parseBindingList,
+  parseImportedIdentifier,
+} from "./lval";
+import {
+  canInsertSemicolon,
+  eatContextual,
+  expect,
+  expectContextual,
+  hasFollowingLineBreak,
+  hasPrecedingLineBreak,
+  isContextual,
+  isLineTerminator,
+  isLookaheadContextual,
+  semicolon,
+  unexpected,
+} from "./util";
+
+export function parseTopLevel() {
+  parseBlockBody(tt.eof);
+  state.scopes.push(new Scope(0, state.tokens.length, true));
+  if (state.scopeDepth !== 0) {
+    throw new Error(`Invalid scope depth at end of file: ${state.scopeDepth}`);
+  }
+  return new File(state.tokens, state.scopes);
+}
+
+// Parse a single statement.
+//
+// If expecting a statement and finding a slash operator, parse a
+// regular expression literal. This is to handle cases like
+// `if (foo) /blah/.exec(foo)`, where looking at the previous token
+// does not help.
+
+export function parseStatement(declaration) {
+  if (isFlowEnabled) {
+    if (flowTryParseStatement()) {
+      return;
+    }
+  }
+  if (match(tt.at)) {
+    parseDecorators();
+  }
+  parseStatementContent(declaration);
+}
+
+function parseStatementContent(declaration) {
+  if (isTypeScriptEnabled) {
+    if (tsTryParseStatementContent()) {
+      return;
+    }
+  }
+
+  const starttype = state.type;
+
+  // Most types of statements are recognized by the keyword they
+  // start with. Many are trivial to parse, some require a bit of
+  // complexity.
+
+  switch (starttype) {
+    case tt._break:
+    case tt._continue:
+      parseBreakContinueStatement();
+      return;
+    case tt._debugger:
+      parseDebuggerStatement();
+      return;
+    case tt._do:
+      parseDoStatement();
+      return;
+    case tt._for:
+      parseForStatement();
+      return;
+    case tt._function:
+      if (lookaheadType() === tt.dot) break;
+      if (!declaration) unexpected();
+      parseFunctionStatement();
+      return;
+
+    case tt._class:
+      if (!declaration) unexpected();
+      parseClass(true);
+      return;
+
+    case tt._if:
+      parseIfStatement();
+      return;
+    case tt._return:
+      parseReturnStatement();
+      return;
+    case tt._switch:
+      parseSwitchStatement();
+      return;
+    case tt._throw:
+      parseThrowStatement();
+      return;
+    case tt._try:
+      parseTryStatement();
+      return;
+
+    case tt._let:
+    case tt._const:
+      if (!declaration) unexpected(); // NOTE: falls through to _var
+
+    case tt._var:
+      parseVarStatement(starttype !== tt._var);
+      return;
+
+    case tt._while:
+      parseWhileStatement();
+      return;
+    case tt.braceL:
+      parseBlock();
+      return;
+    case tt.semi:
+      parseEmptyStatement();
+      return;
+    case tt._export:
+    case tt._import: {
+      const nextType = lookaheadType();
+      if (nextType === tt.parenL || nextType === tt.dot) {
+        break;
+      }
+      next();
+      if (starttype === tt._import) {
+        parseImport();
+      } else {
+        parseExport();
+      }
+      return;
+    }
+    case tt.name:
+      if (state.contextualKeyword === ContextualKeyword._async) {
+        const functionStart = state.start;
+        // peek ahead and see if next token is a function
+        const snapshot = state.snapshot();
+        next();
+        if (match(tt._function) && !canInsertSemicolon()) {
+          expect(tt._function);
+          parseFunction(functionStart, true);
+          return;
+        } else {
+          state.restoreFromSnapshot(snapshot);
+        }
+      } else if (
+        state.contextualKeyword === ContextualKeyword._using &&
+        !hasFollowingLineBreak() &&
+        // Statements like `using[0]` and `using in foo` aren't actual using
+        // declarations.
+        lookaheadType() === tt.name
+      ) {
+        parseVarStatement(true);
+        return;
+      } else if (startsAwaitUsing()) {
+        expectContextual(ContextualKeyword._await);
+        parseVarStatement(true);
+        return;
+      }
+    default:
+      // Do nothing.
+      break;
+  }
+
+  // If the statement does not start with a statement keyword or a
+  // brace, it's an ExpressionStatement or LabeledStatement. We
+  // simply start parsing an expression, and afterwards, if the
+  // next token is a colon and the expression was a simple
+  // Identifier node, we switch to interpreting it as a label.
+  const initialTokensLength = state.tokens.length;
+  parseExpression();
+  let simpleName = null;
+  if (state.tokens.length === initialTokensLength + 1) {
+    const token = state.tokens[state.tokens.length - 1];
+    if (token.type === tt.name) {
+      simpleName = token.contextualKeyword;
+    }
+  }
+  if (simpleName == null) {
+    semicolon();
+    return;
+  }
+  if (eat(tt.colon)) {
+    parseLabeledStatement();
+  } else {
+    // This was an identifier, so we might want to handle flow/typescript-specific cases.
+    parseIdentifierStatement(simpleName);
+  }
+}
+
+/**
+ * Determine if we're positioned at an `await using` declaration.
+ *
+ * Note that this can happen either in place of a regular variable declaration
+ * or in a loop body, and in both places, there are similar-looking cases where
+ * we need to return false.
+ *
+ * Examples returning true:
+ * await using foo = bar();
+ * for (await using a of b) {}
+ *
+ * Examples returning false:
+ * await using
+ * await using + 1
+ * await using instanceof T
+ * for (await using;;) {}
+ *
+ * For now, we early return if we don't see `await`, then do a simple
+ * backtracking-based lookahead for the `using` and identifier tokens. In the
+ * future, this could be optimized with a character-based approach.
+ */
+function startsAwaitUsing() {
+  if (!isContextual(ContextualKeyword._await)) {
+    return false;
+  }
+  const snapshot = state.snapshot();
+  // await
+  next();
+  if (!isContextual(ContextualKeyword._using) || hasPrecedingLineBreak()) {
+    state.restoreFromSnapshot(snapshot);
+    return false;
+  }
+  // using
+  next();
+  if (!match(tt.name) || hasPrecedingLineBreak()) {
+    state.restoreFromSnapshot(snapshot);
+    return false;
+  }
+  state.restoreFromSnapshot(snapshot);
+  return true;
+}
+
+export function parseDecorators() {
+  while (match(tt.at)) {
+    parseDecorator();
+  }
+}
+
+function parseDecorator() {
+  next();
+  if (eat(tt.parenL)) {
+    parseExpression();
+    expect(tt.parenR);
+  } else {
+    parseIdentifier();
+    while (eat(tt.dot)) {
+      parseIdentifier();
+    }
+    parseMaybeDecoratorArguments();
+  }
+}
+
+function parseMaybeDecoratorArguments() {
+  if (isTypeScriptEnabled) {
+    tsParseMaybeDecoratorArguments();
+  } else {
+    baseParseMaybeDecoratorArguments();
+  }
+}
+
+export function baseParseMaybeDecoratorArguments() {
+  if (eat(tt.parenL)) {
+    parseCallExpressionArguments();
+  }
+}
+
+function parseBreakContinueStatement() {
+  next();
+  if (!isLineTerminator()) {
+    parseIdentifier();
+    semicolon();
+  }
+}
+
+function parseDebuggerStatement() {
+  next();
+  semicolon();
+}
+
+function parseDoStatement() {
+  next();
+  parseStatement(false);
+  expect(tt._while);
+  parseParenExpression();
+  eat(tt.semi);
+}
+
+function parseForStatement() {
+  state.scopeDepth++;
+  const startTokenIndex = state.tokens.length;
+  parseAmbiguousForStatement();
+  const endTokenIndex = state.tokens.length;
+  state.scopes.push(new Scope(startTokenIndex, endTokenIndex, false));
+  state.scopeDepth--;
+}
+
+/**
+ * Determine if this token is a `using` declaration (explicit resource
+ * management) as part of a loop.
+ * https://github.com/tc39/proposal-explicit-resource-management
+ */
+function isUsingInLoop() {
+  if (!isContextual(ContextualKeyword._using)) {
+    return false;
+  }
+  // This must be `for (using of`, where `using` is the name of the loop
+  // variable.
+  if (isLookaheadContextual(ContextualKeyword._of)) {
+    return false;
+  }
+  return true;
+}
+
+// Disambiguating between a `for` and a `for`/`in` or `for`/`of`
+// loop is non-trivial. Basically, we have to parse the init `var`
+// statement or expression, disallowing the `in` operator (see
+// the second parameter to `parseExpression`), and then check
+// whether the next token is `in` or `of`. When there is no init
+// part (semicolon immediately after the opening parenthesis), it
+// is a regular `for` loop.
+function parseAmbiguousForStatement() {
+  next();
+
+  let forAwait = false;
+  if (isContextual(ContextualKeyword._await)) {
+    forAwait = true;
+    next();
+  }
+  expect(tt.parenL);
+
+  if (match(tt.semi)) {
+    if (forAwait) {
+      unexpected();
+    }
+    parseFor();
+    return;
+  }
+
+  const isAwaitUsing = startsAwaitUsing();
+  if (isAwaitUsing || match(tt._var) || match(tt._let) || match(tt._const) || isUsingInLoop()) {
+    if (isAwaitUsing) {
+      expectContextual(ContextualKeyword._await);
+    }
+    next();
+    parseVar(true, state.type !== tt._var);
+    if (match(tt._in) || isContextual(ContextualKeyword._of)) {
+      parseForIn(forAwait);
+      return;
+    }
+    parseFor();
+    return;
+  }
+
+  parseExpression(true);
+  if (match(tt._in) || isContextual(ContextualKeyword._of)) {
+    parseForIn(forAwait);
+    return;
+  }
+  if (forAwait) {
+    unexpected();
+  }
+  parseFor();
+}
+
+function parseFunctionStatement() {
+  const functionStart = state.start;
+  next();
+  parseFunction(functionStart, true);
+}
+
+function parseIfStatement() {
+  next();
+  parseParenExpression();
+  parseStatement(false);
+  if (eat(tt._else)) {
+    parseStatement(false);
+  }
+}
+
+function parseReturnStatement() {
+  next();
+
+  // In `return` (and `break`/`continue`), the keywords with
+  // optional arguments, we eagerly look for a semicolon or the
+  // possibility to insert one.
+
+  if (!isLineTerminator()) {
+    parseExpression();
+    semicolon();
+  }
+}
+
+function parseSwitchStatement() {
+  next();
+  parseParenExpression();
+  state.scopeDepth++;
+  const startTokenIndex = state.tokens.length;
+  expect(tt.braceL);
+
+  // Don't bother validation; just go through any sequence of cases, defaults, and statements.
+  while (!match(tt.braceR) && !state.error) {
+    if (match(tt._case) || match(tt._default)) {
+      const isCase = match(tt._case);
+      next();
+      if (isCase) {
+        parseExpression();
+      }
+      expect(tt.colon);
+    } else {
+      parseStatement(true);
+    }
+  }
+  next(); // Closing brace
+  const endTokenIndex = state.tokens.length;
+  state.scopes.push(new Scope(startTokenIndex, endTokenIndex, false));
+  state.scopeDepth--;
+}
+
+function parseThrowStatement() {
+  next();
+  parseExpression();
+  semicolon();
+}
+
+function parseCatchClauseParam() {
+  parseBindingAtom(true /* isBlockScope */);
+
+  if (isTypeScriptEnabled) {
+    tsTryParseTypeAnnotation();
+  }
+}
+
+function parseTryStatement() {
+  next();
+
+  parseBlock();
+
+  if (match(tt._catch)) {
+    next();
+    let catchBindingStartTokenIndex = null;
+    if (match(tt.parenL)) {
+      state.scopeDepth++;
+      catchBindingStartTokenIndex = state.tokens.length;
+      expect(tt.parenL);
+      parseCatchClauseParam();
+      expect(tt.parenR);
+    }
+    parseBlock();
+    if (catchBindingStartTokenIndex != null) {
+      // We need a special scope for the catch binding which includes the binding itself and the
+      // catch block.
+      const endTokenIndex = state.tokens.length;
+      state.scopes.push(new Scope(catchBindingStartTokenIndex, endTokenIndex, false));
+      state.scopeDepth--;
+    }
+  }
+  if (eat(tt._finally)) {
+    parseBlock();
+  }
+}
+
+export function parseVarStatement(isBlockScope) {
+  next();
+  parseVar(false, isBlockScope);
+  semicolon();
+}
+
+function parseWhileStatement() {
+  next();
+  parseParenExpression();
+  parseStatement(false);
+}
+
+function parseEmptyStatement() {
+  next();
+}
+
+function parseLabeledStatement() {
+  parseStatement(true);
+}
+
+/**
+ * Parse a statement starting with an identifier of the given name. Subclasses match on the name
+ * to handle statements like "declare".
+ */
+function parseIdentifierStatement(contextualKeyword) {
+  if (isTypeScriptEnabled) {
+    tsParseIdentifierStatement(contextualKeyword);
+  } else if (isFlowEnabled) {
+    flowParseIdentifierStatement(contextualKeyword);
+  } else {
+    semicolon();
+  }
+}
+
+// Parse a semicolon-enclosed block of statements.
+export function parseBlock(isFunctionScope = false, contextId = 0) {
+  const startTokenIndex = state.tokens.length;
+  state.scopeDepth++;
+  expect(tt.braceL);
+  if (contextId) {
+    state.tokens[state.tokens.length - 1].contextId = contextId;
+  }
+  parseBlockBody(tt.braceR);
+  if (contextId) {
+    state.tokens[state.tokens.length - 1].contextId = contextId;
+  }
+  const endTokenIndex = state.tokens.length;
+  state.scopes.push(new Scope(startTokenIndex, endTokenIndex, isFunctionScope));
+  state.scopeDepth--;
+}
+
+export function parseBlockBody(end) {
+  while (!eat(end) && !state.error) {
+    parseStatement(true);
+  }
+}
+
+// Parse a regular `for` loop. The disambiguation code in
+// `parseStatement` will already have parsed the init statement or
+// expression.
+
+function parseFor() {
+  expect(tt.semi);
+  if (!match(tt.semi)) {
+    parseExpression();
+  }
+  expect(tt.semi);
+  if (!match(tt.parenR)) {
+    parseExpression();
+  }
+  expect(tt.parenR);
+  parseStatement(false);
+}
+
+// Parse a `for`/`in` and `for`/`of` loop, which are almost
+// same from parser's perspective.
+
+function parseForIn(forAwait) {
+  if (forAwait) {
+    eatContextual(ContextualKeyword._of);
+  } else {
+    next();
+  }
+  parseExpression();
+  expect(tt.parenR);
+  parseStatement(false);
+}
+
+// Parse a list of variable declarations.
+
+function parseVar(isFor, isBlockScope) {
+  while (true) {
+    parseVarHead(isBlockScope);
+    if (eat(tt.eq)) {
+      const eqIndex = state.tokens.length - 1;
+      parseMaybeAssign(isFor);
+      state.tokens[eqIndex].rhsEndIndex = state.tokens.length;
+    }
+    if (!eat(tt.comma)) {
+      break;
+    }
+  }
+}
+
+function parseVarHead(isBlockScope) {
+  parseBindingAtom(isBlockScope);
+  if (isTypeScriptEnabled) {
+    tsAfterParseVarHead();
+  } else if (isFlowEnabled) {
+    flowAfterParseVarHead();
+  }
+}
+
+// Parse a function declaration or literal (depending on the
+// `isStatement` parameter).
+
+export function parseFunction(
+  functionStart,
+  isStatement,
+  optionalId = false,
+) {
+  if (match(tt.star)) {
+    next();
+  }
+
+  if (isStatement && !optionalId && !match(tt.name) && !match(tt._yield)) {
+    unexpected();
+  }
+
+  let nameScopeStartTokenIndex = null;
+
+  if (match(tt.name)) {
+    // Expression-style functions should limit their name's scope to the function body, so we make
+    // a new function scope to enforce that.
+    if (!isStatement) {
+      nameScopeStartTokenIndex = state.tokens.length;
+      state.scopeDepth++;
+    }
+    parseBindingIdentifier(false);
+  }
+
+  const startTokenIndex = state.tokens.length;
+  state.scopeDepth++;
+  parseFunctionParams();
+  parseFunctionBodyAndFinish(functionStart);
+  const endTokenIndex = state.tokens.length;
+  // In addition to the block scope of the function body, we need a separate function-style scope
+  // that includes the params.
+  state.scopes.push(new Scope(startTokenIndex, endTokenIndex, true));
+  state.scopeDepth--;
+  if (nameScopeStartTokenIndex !== null) {
+    state.scopes.push(new Scope(nameScopeStartTokenIndex, endTokenIndex, true));
+    state.scopeDepth--;
+  }
+}
+
+export function parseFunctionParams(
+  allowModifiers = false,
+  funcContextId = 0,
+) {
+  if (isTypeScriptEnabled) {
+    tsStartParseFunctionParams();
+  } else if (isFlowEnabled) {
+    flowStartParseFunctionParams();
+  }
+
+  expect(tt.parenL);
+  if (funcContextId) {
+    state.tokens[state.tokens.length - 1].contextId = funcContextId;
+  }
+  parseBindingList(
+    tt.parenR,
+    false /* isBlockScope */,
+    false /* allowEmpty */,
+    allowModifiers,
+    funcContextId,
+  );
+  if (funcContextId) {
+    state.tokens[state.tokens.length - 1].contextId = funcContextId;
+  }
+}
+
+// Parse a class declaration or literal (depending on the
+// `isStatement` parameter).
+
+export function parseClass(isStatement, optionalId = false) {
+  // Put a context ID on the class keyword, the open-brace, and the close-brace, so that later
+  // code can easily navigate to meaningful points on the class.
+  const contextId = getNextContextId();
+
+  next();
+  state.tokens[state.tokens.length - 1].contextId = contextId;
+  state.tokens[state.tokens.length - 1].isExpression = !isStatement;
+  // Like with functions, we declare a special "name scope" from the start of the name to the end
+  // of the class, but only with expression-style classes, to represent the fact that the name is
+  // available to the body of the class but not an outer declaration.
+  let nameScopeStartTokenIndex = null;
+  if (!isStatement) {
+    nameScopeStartTokenIndex = state.tokens.length;
+    state.scopeDepth++;
+  }
+  parseClassId(isStatement, optionalId);
+  parseClassSuper();
+  const openBraceIndex = state.tokens.length;
+  parseClassBody(contextId);
+  if (state.error) {
+    return;
+  }
+  state.tokens[openBraceIndex].contextId = contextId;
+  state.tokens[state.tokens.length - 1].contextId = contextId;
+  if (nameScopeStartTokenIndex !== null) {
+    const endTokenIndex = state.tokens.length;
+    state.scopes.push(new Scope(nameScopeStartTokenIndex, endTokenIndex, false));
+    state.scopeDepth--;
+  }
+}
+
+function isClassProperty() {
+  return match(tt.eq) || match(tt.semi) || match(tt.braceR) || match(tt.bang) || match(tt.colon);
+}
+
+function isClassMethod() {
+  return match(tt.parenL) || match(tt.lessThan);
+}
+
+function parseClassBody(classContextId) {
+  expect(tt.braceL);
+
+  while (!eat(tt.braceR) && !state.error) {
+    if (eat(tt.semi)) {
+      continue;
+    }
+
+    if (match(tt.at)) {
+      parseDecorator();
+      continue;
+    }
+    const memberStart = state.start;
+    parseClassMember(memberStart, classContextId);
+  }
+}
+
+function parseClassMember(memberStart, classContextId) {
+  if (isTypeScriptEnabled) {
+    tsParseModifiers([
+      ContextualKeyword._declare,
+      ContextualKeyword._public,
+      ContextualKeyword._protected,
+      ContextualKeyword._private,
+      ContextualKeyword._override,
+    ]);
+  }
+  let isStatic = false;
+  if (match(tt.name) && state.contextualKeyword === ContextualKeyword._static) {
+    parseIdentifier(); // eats 'static'
+    if (isClassMethod()) {
+      parseClassMethod(memberStart, /* isConstructor */ false);
+      return;
+    } else if (isClassProperty()) {
+      parseClassProperty();
+      return;
+    }
+    // otherwise something static
+    state.tokens[state.tokens.length - 1].type = tt._static;
+    isStatic = true;
+
+    if (match(tt.braceL)) {
+      // This is a static block. Mark the word "static" with the class context ID for class element
+      // detection and parse as a regular block.
+      state.tokens[state.tokens.length - 1].contextId = classContextId;
+      parseBlock();
+      return;
+    }
+  }
+
+  parseClassMemberWithIsStatic(memberStart, isStatic, classContextId);
+}
+
+function parseClassMemberWithIsStatic(
+  memberStart,
+  isStatic,
+  classContextId,
+) {
+  if (isTypeScriptEnabled) {
+    if (tsTryParseClassMemberWithIsStatic(isStatic)) {
+      return;
+    }
+  }
+  if (eat(tt.star)) {
+    // a generator
+    parseClassPropertyName(classContextId);
+    parseClassMethod(memberStart, /* isConstructor */ false);
+    return;
+  }
+
+  // Get the identifier name so we can tell if it's actually a keyword like "async", "get", or
+  // "set".
+  parseClassPropertyName(classContextId);
+  let isConstructor = false;
+  const token = state.tokens[state.tokens.length - 1];
+  // We allow "constructor" as either an identifier or a string.
+  if (token.contextualKeyword === ContextualKeyword._constructor) {
+    isConstructor = true;
+  }
+  parsePostMemberNameModifiers();
+
+  if (isClassMethod()) {
+    parseClassMethod(memberStart, isConstructor);
+  } else if (isClassProperty()) {
+    parseClassProperty();
+  } else if (token.contextualKeyword === ContextualKeyword._async && !isLineTerminator()) {
+    state.tokens[state.tokens.length - 1].type = tt._async;
+    // an async method
+    const isGenerator = match(tt.star);
+    if (isGenerator) {
+      next();
+    }
+
+    // The so-called parsed name would have been "async": get the real name.
+    parseClassPropertyName(classContextId);
+    parsePostMemberNameModifiers();
+    parseClassMethod(memberStart, false /* isConstructor */);
+  } else if (
+    (token.contextualKeyword === ContextualKeyword._get ||
+      token.contextualKeyword === ContextualKeyword._set) &&
+    !(isLineTerminator() && match(tt.star))
+  ) {
+    if (token.contextualKeyword === ContextualKeyword._get) {
+      state.tokens[state.tokens.length - 1].type = tt._get;
+    } else {
+      state.tokens[state.tokens.length - 1].type = tt._set;
+    }
+    // `get\n*` is an uninitialized property named 'get' followed by a generator.
+    // a getter or setter
+    // The so-called parsed name would have been "get/set": get the real name.
+    parseClassPropertyName(classContextId);
+    parseClassMethod(memberStart, /* isConstructor */ false);
+  } else if (token.contextualKeyword === ContextualKeyword._accessor && !isLineTerminator()) {
+    parseClassPropertyName(classContextId);
+    parseClassProperty();
+  } else if (isLineTerminator()) {
+    // an uninitialized class property (due to ASI, since we don't otherwise recognize the next token)
+    parseClassProperty();
+  } else {
+    unexpected();
+  }
+}
+
+function parseClassMethod(functionStart, isConstructor) {
+  if (isTypeScriptEnabled) {
+    tsTryParseTypeParameters();
+  } else if (isFlowEnabled) {
+    if (match(tt.lessThan)) {
+      flowParseTypeParameterDeclaration();
+    }
+  }
+  parseMethod(functionStart, isConstructor);
+}
+
+// Return the name of the class property, if it is a simple identifier.
+export function parseClassPropertyName(classContextId) {
+  parsePropertyName(classContextId);
+}
+
+export function parsePostMemberNameModifiers() {
+  if (isTypeScriptEnabled) {
+    const oldIsType = pushTypeContext(0);
+    eat(tt.question);
+    popTypeContext(oldIsType);
+  }
+}
+
+export function parseClassProperty() {
+  if (isTypeScriptEnabled) {
+    eatTypeToken(tt.bang);
+    tsTryParseTypeAnnotation();
+  } else if (isFlowEnabled) {
+    if (match(tt.colon)) {
+      flowParseTypeAnnotation();
+    }
+  }
+
+  if (match(tt.eq)) {
+    const equalsTokenIndex = state.tokens.length;
+    next();
+    parseMaybeAssign();
+    state.tokens[equalsTokenIndex].rhsEndIndex = state.tokens.length;
+  }
+  semicolon();
+}
+
+function parseClassId(isStatement, optionalId = false) {
+  if (
+    isTypeScriptEnabled &&
+    (!isStatement || optionalId) &&
+    isContextual(ContextualKeyword._implements)
+  ) {
+    return;
+  }
+
+  if (match(tt.name)) {
+    parseBindingIdentifier(true);
+  }
+
+  if (isTypeScriptEnabled) {
+    tsTryParseTypeParameters();
+  } else if (isFlowEnabled) {
+    if (match(tt.lessThan)) {
+      flowParseTypeParameterDeclaration();
+    }
+  }
+}
+
+// Returns true if there was a superclass.
+function parseClassSuper() {
+  let hasSuper = false;
+  if (eat(tt._extends)) {
+    parseExprSubscripts();
+    hasSuper = true;
+  } else {
+    hasSuper = false;
+  }
+  if (isTypeScriptEnabled) {
+    tsAfterParseClassSuper(hasSuper);
+  } else if (isFlowEnabled) {
+    flowAfterParseClassSuper(hasSuper);
+  }
+}
+
+// Parses module export declaration.
+
+export function parseExport() {
+  const exportIndex = state.tokens.length - 1;
+  if (isTypeScriptEnabled) {
+    if (tsTryParseExport()) {
+      return;
+    }
+  }
+  // export * from '...'
+  if (shouldParseExportStar()) {
+    parseExportStar();
+  } else if (isExportDefaultSpecifier()) {
+    // export default from
+    parseIdentifier();
+    if (match(tt.comma) && lookaheadType() === tt.star) {
+      expect(tt.comma);
+      expect(tt.star);
+      expectContextual(ContextualKeyword._as);
+      parseIdentifier();
+    } else {
+      parseExportSpecifiersMaybe();
+    }
+    parseExportFrom();
+  } else if (eat(tt._default)) {
+    // export default ...
+    parseExportDefaultExpression();
+  } else if (shouldParseExportDeclaration()) {
+    parseExportDeclaration();
+  } else {
+    // export { x, y as z } [from '...']
+    parseExportSpecifiers();
+    parseExportFrom();
+  }
+  state.tokens[exportIndex].rhsEndIndex = state.tokens.length;
+}
+
+function parseExportDefaultExpression() {
+  if (isTypeScriptEnabled) {
+    if (tsTryParseExportDefaultExpression()) {
+      return;
+    }
+  }
+  if (isFlowEnabled) {
+    if (flowTryParseExportDefaultExpression()) {
+      return;
+    }
+  }
+  const functionStart = state.start;
+  if (eat(tt._function)) {
+    parseFunction(functionStart, true, true);
+  } else if (isContextual(ContextualKeyword._async) && lookaheadType() === tt._function) {
+    // async function declaration
+    eatContextual(ContextualKeyword._async);
+    eat(tt._function);
+    parseFunction(functionStart, true, true);
+  } else if (match(tt._class)) {
+    parseClass(true, true);
+  } else if (match(tt.at)) {
+    parseDecorators();
+    parseClass(true, true);
+  } else {
+    parseMaybeAssign();
+    semicolon();
+  }
+}
+
+function parseExportDeclaration() {
+  if (isTypeScriptEnabled) {
+    tsParseExportDeclaration();
+  } else if (isFlowEnabled) {
+    flowParseExportDeclaration();
+  } else {
+    parseStatement(true);
+  }
+}
+
+function isExportDefaultSpecifier() {
+  if (isTypeScriptEnabled && tsIsDeclarationStart()) {
+    return false;
+  } else if (isFlowEnabled && flowShouldDisallowExportDefaultSpecifier()) {
+    return false;
+  }
+  if (match(tt.name)) {
+    return state.contextualKeyword !== ContextualKeyword._async;
+  }
+
+  if (!match(tt._default)) {
+    return false;
+  }
+
+  const _next = nextTokenStart();
+  const lookahead = lookaheadTypeAndKeyword();
+  const hasFrom =
+    lookahead.type === tt.name && lookahead.contextualKeyword === ContextualKeyword._from;
+  if (lookahead.type === tt.comma) {
+    return true;
+  }
+  // lookahead again when `export default from` is seen
+  if (hasFrom) {
+    const nextAfterFrom = input.charCodeAt(nextTokenStartSince(_next + 4));
+    return nextAfterFrom === charCodes.quotationMark || nextAfterFrom === charCodes.apostrophe;
+  }
+  return false;
+}
+
+function parseExportSpecifiersMaybe() {
+  if (eat(tt.comma)) {
+    parseExportSpecifiers();
+  }
+}
+
+export function parseExportFrom() {
+  if (eatContextual(ContextualKeyword._from)) {
+    parseExprAtom();
+    maybeParseImportAttributes();
+  }
+  semicolon();
+}
+
+function shouldParseExportStar() {
+  if (isFlowEnabled) {
+    return flowShouldParseExportStar();
+  } else {
+    return match(tt.star);
+  }
+}
+
+function parseExportStar() {
+  if (isFlowEnabled) {
+    flowParseExportStar();
+  } else {
+    baseParseExportStar();
+  }
+}
+
+export function baseParseExportStar() {
+  expect(tt.star);
+
+  if (isContextual(ContextualKeyword._as)) {
+    parseExportNamespace();
+  } else {
+    parseExportFrom();
+  }
+}
+
+function parseExportNamespace() {
+  next();
+  state.tokens[state.tokens.length - 1].type = tt._as;
+  parseIdentifier();
+  parseExportSpecifiersMaybe();
+  parseExportFrom();
+}
+
+function shouldParseExportDeclaration() {
+  return (
+    (isTypeScriptEnabled && tsIsDeclarationStart()) ||
+    (isFlowEnabled && flowShouldParseExportDeclaration()) ||
+    state.type === tt._var ||
+    state.type === tt._const ||
+    state.type === tt._let ||
+    state.type === tt._function ||
+    state.type === tt._class ||
+    isContextual(ContextualKeyword._async) ||
+    match(tt.at)
+  );
+}
+
+// Parses a comma-separated list of module exports.
+export function parseExportSpecifiers() {
+  let first = true;
+
+  // export { x, y as z } [from '...']
+  expect(tt.braceL);
+
+  while (!eat(tt.braceR) && !state.error) {
+    if (first) {
+      first = false;
+    } else {
+      expect(tt.comma);
+      if (eat(tt.braceR)) {
+        break;
+      }
+    }
+    parseExportSpecifier();
+  }
+}
+
+function parseExportSpecifier() {
+  if (isTypeScriptEnabled) {
+    tsParseExportSpecifier();
+    return;
+  }
+  parseIdentifier();
+  state.tokens[state.tokens.length - 1].identifierRole = IdentifierRole.ExportAccess;
+  if (eatContextual(ContextualKeyword._as)) {
+    parseIdentifier();
+  }
+}
+
+/**
+ * Starting at the `module` token in an import, determine if it was truly an
+ * import reflection token or just looks like one.
+ *
+ * Returns true for:
+ * import module foo from "foo";
+ * import module from from "foo";
+ *
+ * Returns false for:
+ * import module from "foo";
+ * import module, {bar} from "foo";
+ */
+function isImportReflection() {
+  const snapshot = state.snapshot();
+  expectContextual(ContextualKeyword._module);
+  if (eatContextual(ContextualKeyword._from)) {
+    if (isContextual(ContextualKeyword._from)) {
+      state.restoreFromSnapshot(snapshot);
+      return true;
+    } else {
+      state.restoreFromSnapshot(snapshot);
+      return false;
+    }
+  } else if (match(tt.comma)) {
+    state.restoreFromSnapshot(snapshot);
+    return false;
+  } else {
+    state.restoreFromSnapshot(snapshot);
+    return true;
+  }
+}
+
+/**
+ * Eat the "module" token from the import reflection proposal.
+ * https://github.com/tc39/proposal-import-reflection
+ */
+function parseMaybeImportReflection() {
+  // isImportReflection does snapshot/restore, so only run it if we see the word
+  // "module".
+  if (isContextual(ContextualKeyword._module) && isImportReflection()) {
+    next();
+  }
+}
+
+// Parses import declaration.
+
+export function parseImport() {
+  if (isTypeScriptEnabled && match(tt.name) && lookaheadType() === tt.eq) {
+    tsParseImportEqualsDeclaration();
+    return;
+  }
+  if (isTypeScriptEnabled && isContextual(ContextualKeyword._type)) {
+    const lookahead = lookaheadTypeAndKeyword();
+    if (lookahead.type === tt.name && lookahead.contextualKeyword !== ContextualKeyword._from) {
+      // One of these `import type` cases:
+      // import type T = require('T');
+      // import type A from 'A';
+      expectContextual(ContextualKeyword._type);
+      if (lookaheadType() === tt.eq) {
+        tsParseImportEqualsDeclaration();
+        return;
+      }
+      // If this is an `import type...from` statement, then we already ate the
+      // type token, so proceed to the regular import parser.
+    } else if (lookahead.type === tt.star || lookahead.type === tt.braceL) {
+      // One of these `import type` cases, in which case we can eat the type token
+      // and proceed as normal:
+      // import type * as A from 'A';
+      // import type {a} from 'A';
+      expectContextual(ContextualKeyword._type);
+    }
+    // Otherwise, we are importing the name "type".
+  }
+
+  // import '...'
+  if (match(tt.string)) {
+    parseExprAtom();
+  } else {
+    parseMaybeImportReflection();
+    parseImportSpecifiers();
+    expectContextual(ContextualKeyword._from);
+    parseExprAtom();
+  }
+  maybeParseImportAttributes();
+  semicolon();
+}
+
+// eslint-disable-next-line no-unused-vars
+function shouldParseDefaultImport() {
+  return match(tt.name);
+}
+
+function parseImportSpecifierLocal() {
+  parseImportedIdentifier();
+}
+
+// Parses a comma-separated list of module imports.
+function parseImportSpecifiers() {
+  if (isFlowEnabled) {
+    flowStartParseImportSpecifiers();
+  }
+
+  let first = true;
+  if (shouldParseDefaultImport()) {
+    // import defaultObj, { x, y as z } from '...'
+    parseImportSpecifierLocal();
+
+    if (!eat(tt.comma)) return;
+  }
+
+  if (match(tt.star)) {
+    next();
+    expectContextual(ContextualKeyword._as);
+
+    parseImportSpecifierLocal();
+
+    return;
+  }
+
+  expect(tt.braceL);
+  while (!eat(tt.braceR) && !state.error) {
+    if (first) {
+      first = false;
+    } else {
+      // Detect an attempt to deep destructure
+      if (eat(tt.colon)) {
+        unexpected(
+          "ES2015 named imports do not destructure. Use another statement for destructuring after the import.",
+        );
+      }
+
+      expect(tt.comma);
+      if (eat(tt.braceR)) {
+        break;
+      }
+    }
+
+    parseImportSpecifier();
+  }
+}
+
+function parseImportSpecifier() {
+  if (isTypeScriptEnabled) {
+    tsParseImportSpecifier();
+    return;
+  }
+  if (isFlowEnabled) {
+    flowParseImportSpecifier();
+    return;
+  }
+  parseImportedIdentifier();
+  if (isContextual(ContextualKeyword._as)) {
+    state.tokens[state.tokens.length - 1].identifierRole = IdentifierRole.ImportAccess;
+    next();
+    parseImportedIdentifier();
+  }
+}
+
+/**
+ * Parse import attributes like `with {type: "json"}`, or the legacy form
+ * `assert {type: "json"}`.
+ *
+ * Import attributes technically have their own syntax, but are always parseable
+ * as a plain JS object, so just do that for simplicity.
+ */
+function maybeParseImportAttributes() {
+  if (match(tt._with) || (isContextual(ContextualKeyword._assert) && !hasPrecedingLineBreak())) {
+    next();
+    parseObj(false, false);
+  }
+}