source: imaps-frontend/node_modules/strip-json-comments/index.js

'use strict';
const singleComment = Symbol('singleComment');
const multiComment = Symbol('multiComment');
const stripWithoutWhitespace = () => '';
const stripWithWhitespace = (string, start, end) => string.slice(start, end).replace(/\S/g, ' ');

const isEscaped = (jsonString, quotePosition) => {
        let index = quotePosition - 1;
        let backslashCount = 0;

        while (jsonString[index] === '\\') {
                index -= 1;
                backslashCount += 1;
        }

        return Boolean(backslashCount % 2);
};

module.exports = (jsonString, options = {}) => {
        if (typeof jsonString !== 'string') {
                throw new TypeError(`Expected argument \`jsonString\` to be a \`string\`, got \`${typeof jsonString}\``);
        }

        const strip = options.whitespace === false ? stripWithoutWhitespace : stripWithWhitespace;

        let insideString = false;
        let insideComment = false;
        let offset = 0;
        let result = '';

        for (let i = 0; i < jsonString.length; i++) {
                const currentCharacter = jsonString[i];
                const nextCharacter = jsonString[i + 1];

                if (!insideComment && currentCharacter === '"') {
                        const escaped = isEscaped(jsonString, i);
                        if (!escaped) {
                                insideString = !insideString;
                        }
                }

                if (insideString) {
                        continue;
                }

                if (!insideComment && currentCharacter + nextCharacter === '//') {
                        result += jsonString.slice(offset, i);
                        offset = i;
                        insideComment = singleComment;
                        i++;
                } else if (insideComment === singleComment && currentCharacter + nextCharacter === '\r\n') {
                        i++;
                        insideComment = false;
                        result += strip(jsonString, offset, i);
                        offset = i;
                        continue;
                } else if (insideComment === singleComment && currentCharacter === '\n') {
                        insideComment = false;
                        result += strip(jsonString, offset, i);
                        offset = i;
                } else if (!insideComment && currentCharacter + nextCharacter === '/*') {
                        result += jsonString.slice(offset, i);
                        offset = i;
                        insideComment = multiComment;
                        i++;
                        continue;
                } else if (insideComment === multiComment && currentCharacter + nextCharacter === '*/') {
                        i++;
                        insideComment = false;
                        result += strip(jsonString, offset, i + 1);
                        offset = i + 1;
                        continue;
                }
        }

        return result + (insideComment ? strip(jsonString.slice(offset)) : jsonString.slice(offset));
};