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+"use strict";Object.defineProperty(exports, "__esModule", {value: true});var _index = require('../tokenizer/index');
+
+var _types = require('../tokenizer/types');
+var _charcodes = require('../util/charcodes');
+var _base = require('./base');
+
+// ## Parser utilities
+
+// Tests whether parsed token is a contextual keyword.
+ function isContextual(contextualKeyword) {
+ return _base.state.contextualKeyword === contextualKeyword;
+} exports.isContextual = isContextual;
+
+ function isLookaheadContextual(contextualKeyword) {
+ const l = _index.lookaheadTypeAndKeyword.call(void 0, );
+ return l.type === _types.TokenType.name && l.contextualKeyword === contextualKeyword;
+} exports.isLookaheadContextual = isLookaheadContextual;
+
+// Consumes contextual keyword if possible.
+ function eatContextual(contextualKeyword) {
+ return _base.state.contextualKeyword === contextualKeyword && _index.eat.call(void 0, _types.TokenType.name);
+} exports.eatContextual = eatContextual;
+
+// Asserts that following token is given contextual keyword.
+ function expectContextual(contextualKeyword) {
+ if (!eatContextual(contextualKeyword)) {
+ unexpected();
+ }
+} exports.expectContextual = expectContextual;
+
+// Test whether a semicolon can be inserted at the current position.
+ function canInsertSemicolon() {
+ return _index.match.call(void 0, _types.TokenType.eof) || _index.match.call(void 0, _types.TokenType.braceR) || hasPrecedingLineBreak();
+} exports.canInsertSemicolon = canInsertSemicolon;
+
+ function hasPrecedingLineBreak() {
+ const prevToken = _base.state.tokens[_base.state.tokens.length - 1];
+ const lastTokEnd = prevToken ? prevToken.end : 0;
+ for (let i = lastTokEnd; i < _base.state.start; i++) {
+ const code = _base.input.charCodeAt(i);
+ if (
+ code === _charcodes.charCodes.lineFeed ||
+ code === _charcodes.charCodes.carriageReturn ||
+ code === 0x2028 ||
+ code === 0x2029
+ ) {
+ return true;
+ }
+ }
+ return false;
+} exports.hasPrecedingLineBreak = hasPrecedingLineBreak;
+
+ function hasFollowingLineBreak() {
+ const nextStart = _index.nextTokenStart.call(void 0, );
+ for (let i = _base.state.end; i < nextStart; i++) {
+ const code = _base.input.charCodeAt(i);
+ if (
+ code === _charcodes.charCodes.lineFeed ||
+ code === _charcodes.charCodes.carriageReturn ||
+ code === 0x2028 ||
+ code === 0x2029
+ ) {
+ return true;
+ }
+ }
+ return false;
+} exports.hasFollowingLineBreak = hasFollowingLineBreak;
+
+ function isLineTerminator() {
+ return _index.eat.call(void 0, _types.TokenType.semi) || canInsertSemicolon();
+} exports.isLineTerminator = isLineTerminator;
+
+// Consume a semicolon, or, failing that, see if we are allowed to
+// pretend that there is a semicolon at this position.
+ function semicolon() {
+ if (!isLineTerminator()) {
+ unexpected('Unexpected token, expected ";"');
+ }
+} exports.semicolon = semicolon;
+
+// Expect a token of a given type. If found, consume it, otherwise,
+// raise an unexpected token error at given pos.
+ function expect(type) {
+ const matched = _index.eat.call(void 0, type);
+ if (!matched) {
+ unexpected(`Unexpected token, expected "${_types.formatTokenType.call(void 0, type)}"`);
+ }
+} exports.expect = expect;
+
+/**
+ * Transition the parser to an error state. All code needs to be written to naturally unwind in this
+ * state, which allows us to backtrack without exceptions and without error plumbing everywhere.
+ */
+ function unexpected(message = "Unexpected token", pos = _base.state.start) {
+ if (_base.state.error) {
+ return;
+ }
+ // eslint-disable-next-line @typescript-eslint/no-explicit-any
+ const err = new SyntaxError(message);
+ err.pos = pos;
+ _base.state.error = err;
+ _base.state.pos = _base.input.length;
+ _index.finishToken.call(void 0, _types.TokenType.eof);
+} exports.unexpected = unexpected;