const createCustomError = require('../utils/createCustomError'); const generate = require('../definition-syntax/generate'); const defaultLoc = { offset: 0, line: 1, column: 1 }; function locateMismatch(matchResult, node) { const tokens = matchResult.tokens; const longestMatch = matchResult.longestMatch; const mismatchNode = longestMatch < tokens.length ? tokens[longestMatch].node || null : null; const badNode = mismatchNode !== node ? mismatchNode : null; let mismatchOffset = 0; let mismatchLength = 0; let entries = 0; let css = ''; let start; let end; for (let i = 0; i < tokens.length; i++) { const token = tokens[i].value; if (i === longestMatch) { mismatchLength = token.length; mismatchOffset = css.length; } if (badNode !== null && tokens[i].node === badNode) { if (i <= longestMatch) { entries++; } else { entries = 0; } } css += token; } if (longestMatch === tokens.length || entries > 1) { // last start = fromLoc(badNode || node, 'end') || buildLoc(defaultLoc, css); end = buildLoc(start); } else { start = fromLoc(badNode, 'start') || buildLoc(fromLoc(node, 'start') || defaultLoc, css.slice(0, mismatchOffset)); end = fromLoc(badNode, 'end') || buildLoc(start, css.substr(mismatchOffset, mismatchLength)); } return { css, mismatchOffset, mismatchLength, start, end }; } function fromLoc(node, point) { const value = node && node.loc && node.loc[point]; if (value) { return 'line' in value ? buildLoc(value) : value; } return null; } function buildLoc({ offset, line, column }, extra) { const loc = { offset, line, column }; if (extra) { const lines = extra.split(/\n|\r\n?|\f/); loc.offset += extra.length; loc.line += lines.length - 1; loc.column = lines.length === 1 ? loc.column + extra.length : lines.pop().length + 1; } return loc; } const SyntaxReferenceError = function(type, referenceName) { const error = createCustomError( 'SyntaxReferenceError', type + (referenceName ? ' `' + referenceName + '`' : '') ); error.reference = referenceName; return error; }; const SyntaxMatchError = function(message, syntax, node, matchResult) { const error = createCustomError('SyntaxMatchError', message); const { css, mismatchOffset, mismatchLength, start, end } = locateMismatch(matchResult, node); error.rawMessage = message; error.syntax = syntax ? generate(syntax) : ''; error.css = css; error.mismatchOffset = mismatchOffset; error.mismatchLength = mismatchLength; error.message = message + '\n' + ' syntax: ' + error.syntax + '\n' + ' value: ' + (css || '') + '\n' + ' --------' + new Array(error.mismatchOffset + 1).join('-') + '^'; Object.assign(error, start); error.loc = { source: (node && node.loc && node.loc.source) || '', start, end }; return error; }; module.exports = { SyntaxReferenceError, SyntaxMatchError };