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