str-utils.js

const REGEX_NON_ASCII_CHARS = /[\u00A0-\u9999]/g;
const REGEX_SPECIAL_CHARS = /[<>"'`&?=\\/()\[\]\{\}\#]/g;

let replaceCharWithHtmlEntity = char => `&#${char.charCodeAt(0)};`;

let htmlEncode = str => str.replace(REGEX_NON_ASCII_CHARS, replaceCharWithHtmlEntity)
                           .replace(REGEX_SPECIAL_CHARS, replaceCharWithHtmlEntity);

let urlEncode = str => encodeURIComponent(str);

let slug = str => {
    str = str.toLowerCase();

    let from = 'àáâãäåçèéêëìíîïðñòóôõöøùúûüýÿ',
        to   = 'aaaaaaceeeeiiiidnoooooouuuuyy';

    for (let i = 0, l = from.length; i < l; i++) {
        str = str.replace(new RegExp(from.charAt(i), 'g'), to.charAt(i));
    }

    let translit = {
        "æ": 'ae',
        "ß": 'ss',
        "þ": 'th',
    };

    for (let char in translit) {
        str = str.replace(new RegExp(char, 'g'), tanslit[char]);
    }

    return str.replace(/[^a-z0-9]+/g, ' ')
              .trim()
              .replace(/\s+/g, '-');
}

export default {
    htmlEncode,
    urlEncode,
    slug
};