import { createCustomError } from '../utils/create-custom-error.js'; const MAX_LINE_LENGTH = 100; const OFFSET_CORRECTION = 60; const TAB_REPLACEMENT = ' '; function sourceFragment({ source, line, column }, extraLines) { function processLines(start, end) { return lines .slice(start, end) .map((line, idx) => String(start + idx + 1).padStart(maxNumLength) + ' |' + line ).join('\n'); } const lines = source.split(/\r\n?|\n|\f/); const startLine = Math.max(1, line - extraLines) - 1; const endLine = Math.min(line + extraLines, lines.length + 1); const maxNumLength = Math.max(4, String(endLine).length) + 1; let cutLeft = 0; // column correction according to replaced tab before column column += (TAB_REPLACEMENT.length - 1) * (lines[line - 1].substr(0, column - 1).match(/\t/g) || []).length; if (column > MAX_LINE_LENGTH) { cutLeft = column - OFFSET_CORRECTION + 3; column = OFFSET_CORRECTION - 2; } for (let i = startLine; i <= endLine; i++) { if (i >= 0 && i < lines.length) { lines[i] = lines[i].replace(/\t/g, TAB_REPLACEMENT); lines[i] = (cutLeft > 0 && lines[i].length > cutLeft ? '\u2026' : '') + lines[i].substr(cutLeft, MAX_LINE_LENGTH - 2) + (lines[i].length > cutLeft + MAX_LINE_LENGTH - 1 ? '\u2026' : ''); } } return [ processLines(startLine, line), new Array(column + maxNumLength + 2).join('-') + '^', processLines(line, endLine) ].filter(Boolean).join('\n'); } export function SyntaxError(message, source, offset, line, column) { const error = Object.assign(createCustomError('SyntaxError', message), { source, offset, line, column, sourceFragment(extraLines) { return sourceFragment({ source, line, column }, isNaN(extraLines) ? 0 : extraLines); }, get formattedMessage() { return ( `Parse error: ${message}\n` + sourceFragment({ source, line, column }, 2) ); } }); return error; }