226 lines
		
	
	
		
			7.2 KiB
		
	
	
	
		
			JavaScript
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			226 lines
		
	
	
		
			7.2 KiB
		
	
	
	
		
			JavaScript
		
	
	
		
			Executable File
		
	
	
	
	
| 'use strict';
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| 
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| var Scalar = require('../nodes/Scalar.js');
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| var resolveEnd = require('./resolve-end.js');
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| 
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| function resolveFlowScalar(scalar, strict, onError) {
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|     const { offset, type, source, end } = scalar;
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|     let _type;
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|     let value;
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|     const _onError = (rel, code, msg) => onError(offset + rel, code, msg);
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|     switch (type) {
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|         case 'scalar':
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|             _type = Scalar.Scalar.PLAIN;
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|             value = plainValue(source, _onError);
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|             break;
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|         case 'single-quoted-scalar':
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|             _type = Scalar.Scalar.QUOTE_SINGLE;
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|             value = singleQuotedValue(source, _onError);
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|             break;
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|         case 'double-quoted-scalar':
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|             _type = Scalar.Scalar.QUOTE_DOUBLE;
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|             value = doubleQuotedValue(source, _onError);
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|             break;
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|         /* istanbul ignore next should not happen */
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|         default:
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|             onError(scalar, 'UNEXPECTED_TOKEN', `Expected a flow scalar value, but found: ${type}`);
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|             return {
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|                 value: '',
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|                 type: null,
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|                 comment: '',
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|                 range: [offset, offset + source.length, offset + source.length]
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|             };
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|     }
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|     const valueEnd = offset + source.length;
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|     const re = resolveEnd.resolveEnd(end, valueEnd, strict, onError);
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|     return {
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|         value,
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|         type: _type,
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|         comment: re.comment,
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|         range: [offset, valueEnd, re.offset]
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|     };
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| }
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| function plainValue(source, onError) {
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|     let badChar = '';
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|     switch (source[0]) {
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|         /* istanbul ignore next should not happen */
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|         case '\t':
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|             badChar = 'a tab character';
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|             break;
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|         case ',':
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|             badChar = 'flow indicator character ,';
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|             break;
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|         case '%':
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|             badChar = 'directive indicator character %';
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|             break;
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|         case '|':
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|         case '>': {
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|             badChar = `block scalar indicator ${source[0]}`;
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|             break;
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|         }
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|         case '@':
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|         case '`': {
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|             badChar = `reserved character ${source[0]}`;
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|             break;
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|         }
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|     }
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|     if (badChar)
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|         onError(0, 'BAD_SCALAR_START', `Plain value cannot start with ${badChar}`);
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|     return foldLines(source);
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| }
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| function singleQuotedValue(source, onError) {
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|     if (source[source.length - 1] !== "'" || source.length === 1)
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|         onError(source.length, 'MISSING_CHAR', "Missing closing 'quote");
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|     return foldLines(source.slice(1, -1)).replace(/''/g, "'");
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| }
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| function foldLines(source) {
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|     /**
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|      * The negative lookbehind here and in the `re` RegExp is to
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|      * prevent causing a polynomial search time in certain cases.
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|      *
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|      * The try-catch is for Safari, which doesn't support this yet:
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|      * https://caniuse.com/js-regexp-lookbehind
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|      */
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|     let first, line;
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|     try {
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|         first = new RegExp('(.*?)(?<![ \t])[ \t]*\r?\n', 'sy');
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|         line = new RegExp('[ \t]*(.*?)(?:(?<![ \t])[ \t]*)?\r?\n', 'sy');
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|     }
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|     catch {
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|         first = /(.*?)[ \t]*\r?\n/sy;
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|         line = /[ \t]*(.*?)[ \t]*\r?\n/sy;
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|     }
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|     let match = first.exec(source);
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|     if (!match)
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|         return source;
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|     let res = match[1];
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|     let sep = ' ';
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|     let pos = first.lastIndex;
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|     line.lastIndex = pos;
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|     while ((match = line.exec(source))) {
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|         if (match[1] === '') {
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|             if (sep === '\n')
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|                 res += sep;
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|             else
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|                 sep = '\n';
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|         }
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|         else {
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|             res += sep + match[1];
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|             sep = ' ';
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|         }
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|         pos = line.lastIndex;
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|     }
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|     const last = /[ \t]*(.*)/sy;
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|     last.lastIndex = pos;
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|     match = last.exec(source);
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|     return res + sep + (match?.[1] ?? '');
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| }
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| function doubleQuotedValue(source, onError) {
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|     let res = '';
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|     for (let i = 1; i < source.length - 1; ++i) {
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|         const ch = source[i];
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|         if (ch === '\r' && source[i + 1] === '\n')
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|             continue;
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|         if (ch === '\n') {
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|             const { fold, offset } = foldNewline(source, i);
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|             res += fold;
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|             i = offset;
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|         }
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|         else if (ch === '\\') {
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|             let next = source[++i];
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|             const cc = escapeCodes[next];
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|             if (cc)
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|                 res += cc;
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|             else if (next === '\n') {
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|                 // skip escaped newlines, but still trim the following line
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|                 next = source[i + 1];
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|                 while (next === ' ' || next === '\t')
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|                     next = source[++i + 1];
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|             }
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|             else if (next === '\r' && source[i + 1] === '\n') {
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|                 // skip escaped CRLF newlines, but still trim the following line
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|                 next = source[++i + 1];
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|                 while (next === ' ' || next === '\t')
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|                     next = source[++i + 1];
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|             }
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|             else if (next === 'x' || next === 'u' || next === 'U') {
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|                 const length = { x: 2, u: 4, U: 8 }[next];
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|                 res += parseCharCode(source, i + 1, length, onError);
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|                 i += length;
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|             }
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|             else {
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|                 const raw = source.substr(i - 1, 2);
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|                 onError(i - 1, 'BAD_DQ_ESCAPE', `Invalid escape sequence ${raw}`);
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|                 res += raw;
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|             }
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|         }
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|         else if (ch === ' ' || ch === '\t') {
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|             // trim trailing whitespace
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|             const wsStart = i;
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|             let next = source[i + 1];
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|             while (next === ' ' || next === '\t')
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|                 next = source[++i + 1];
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|             if (next !== '\n' && !(next === '\r' && source[i + 2] === '\n'))
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|                 res += i > wsStart ? source.slice(wsStart, i + 1) : ch;
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|         }
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|         else {
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|             res += ch;
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|         }
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|     }
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|     if (source[source.length - 1] !== '"' || source.length === 1)
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|         onError(source.length, 'MISSING_CHAR', 'Missing closing "quote');
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|     return res;
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| }
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| /**
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|  * Fold a single newline into a space, multiple newlines to N - 1 newlines.
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|  * Presumes `source[offset] === '\n'`
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|  */
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| function foldNewline(source, offset) {
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|     let fold = '';
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|     let ch = source[offset + 1];
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|     while (ch === ' ' || ch === '\t' || ch === '\n' || ch === '\r') {
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|         if (ch === '\r' && source[offset + 2] !== '\n')
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|             break;
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|         if (ch === '\n')
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|             fold += '\n';
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|         offset += 1;
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|         ch = source[offset + 1];
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|     }
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|     if (!fold)
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|         fold = ' ';
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|     return { fold, offset };
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| }
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| const escapeCodes = {
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|     '0': '\0', // null character
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|     a: '\x07', // bell character
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|     b: '\b', // backspace
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|     e: '\x1b', // escape character
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|     f: '\f', // form feed
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|     n: '\n', // line feed
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|     r: '\r', // carriage return
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|     t: '\t', // horizontal tab
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|     v: '\v', // vertical tab
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|     N: '\u0085', // Unicode next line
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|     _: '\u00a0', // Unicode non-breaking space
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|     L: '\u2028', // Unicode line separator
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|     P: '\u2029', // Unicode paragraph separator
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|     ' ': ' ',
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|     '"': '"',
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|     '/': '/',
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|     '\\': '\\',
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|     '\t': '\t'
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| };
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| function parseCharCode(source, offset, length, onError) {
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|     const cc = source.substr(offset, length);
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|     const ok = cc.length === length && /^[0-9a-fA-F]+$/.test(cc);
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|     const code = ok ? parseInt(cc, 16) : NaN;
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|     if (isNaN(code)) {
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|         const raw = source.substr(offset - 2, length + 2);
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|         onError(offset - 2, 'BAD_DQ_ESCAPE', `Invalid escape sequence ${raw}`);
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|         return raw;
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|     }
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|     return String.fromCodePoint(code);
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| }
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| 
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| exports.resolveFlowScalar = resolveFlowScalar;
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