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JavaScript

"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;