'use strict'; const balancedMatch = require('balanced-match'); /** * Replace all of the characters that are arguments to a certain * CSS function with some innocuous character. * * This is useful if you need to use a RegExp to find a string * but want to ignore matches in certain functions (e.g. `url()`, * which might contain all kinds of false positives). * * For example: * blurFunctionArguments("abc url(abc) abc", "url") === "abc url(```) abc" * * @param {string} source * @param {string} functionName * @return {string} - The result string, with the function arguments "blurred" */ module.exports = function (source, functionName, blurChar = '`') { const nameWithParen = `${functionName.toLowerCase()}(`; const lowerCaseSource = source.toLowerCase(); if (!lowerCaseSource.includes(nameWithParen)) { return source; } const functionNameLength = functionName.length; let result = source; let searchStartIndex = 0; while (lowerCaseSource.includes(nameWithParen, searchStartIndex)) { const openingParenIndex = lowerCaseSource.indexOf(nameWithParen, searchStartIndex) + functionNameLength; const parensMatch = balancedMatch('(', ')', lowerCaseSource.slice(openingParenIndex)); if (!parensMatch) { throw new Error(`No parens match: "${source}"`); } const closingParenIndex = parensMatch.end + openingParenIndex; const argumentsLength = closingParenIndex - openingParenIndex - 1; result = result.slice(0, openingParenIndex + 1) + blurChar.repeat(argumentsLength) + result.slice(closingParenIndex); searchStartIndex = closingParenIndex; } return result; };