htmlnano/dist/_modules/removeEmptyAttributes.js

Modular HTML minifier, built on top of the PostHTML

Object.defineProperty(exports, '__esModule', { value: true });

var helpers_js = require('../helpers.js');

const safeToRemoveAttrs = {
    id: null,
    class: null,
    style: null,
    title: null,
    lang: null,
    dir: null,
    abbr: [
        'th'
    ],
    accept: [
        'input'
    ],
    'accept-charset': [
        'form'
    ],
    charset: [
        'meta',
        'script'
    ],
    action: [
        'form'
    ],
    cols: [
        'textarea'
    ],
    colspan: [
        'td',
        'th'
    ],
    coords: [
        'area'
    ],
    dirname: [
        'input',
        'textarea'
    ],
    dropzone: null,
    headers: [
        'td',
        'th'
    ],
    form: [
        'button',
        'fieldset',
        'input',
        'keygen',
        'object',
        'output',
        'select',
        'textarea'
    ],
    formaction: [
        'button',
        'input'
    ],
    height: [
        'canvas',
        'embed',
        'iframe',
        'img',
        'input',
        'object',
        'video'
    ],
    high: [
        'meter'
    ],
    href: [
        'link'
    ],
    list: [
        'input'
    ],
    low: [
        'meter'
    ],
    manifest: [
        'html'
    ],
    max: [
        'meter',
        'progress'
    ],
    maxlength: [
        'input',
        'textarea'
    ],
    menu: [
        'button'
    ],
    min: [
        'meter'
    ],
    minlength: [
        'input',
        'textarea'
    ],
    name: [
        'button',
        'fieldset',
        'input',
        'keygen',
        'output',
        'select',
        'textarea',
        'form',
        'map',
        'meta',
        'param',
        'slot'
    ],
    pattern: [
        'input'
    ],
    ping: [
        'a',
        'area'
    ],
    placeholder: [
        'input',
        'textarea'
    ],
    poster: [
        'video'
    ],
    rel: [
        'a',
        'area',
        'link'
    ],
    rows: [
        'textarea'
    ],
    rowspan: [
        'td',
        'th'
    ],
    size: [
        'input',
        'select'
    ],
    span: [
        'col',
        'colgroup'
    ],
    src: [
        'audio',
        'embed',
        'iframe',
        'img',
        'input',
        'script',
        'source',
        'track',
        'video'
    ],
    start: [
        'ol'
    ],
    tabindex: null,
    type: [
        'a',
        'link',
        'button',
        'embed',
        'object',
        'script',
        'source',
        'style',
        'input',
        'menu',
        'menuitem',
        'ol'
    ],
    value: [
        'button',
        'input',
        'li'
    ],
    width: [
        'canvas',
        'embed',
        'iframe',
        'img',
        'input',
        'object',
        'video'
    ]
};
const mod = {
    onAttrs () {
        return (attrs, node)=>{
            const newAttrs = {
                ...attrs
            };
            const tagName = typeof node.tag === 'string' ? node.tag.toLowerCase() : '';
            Object.entries(attrs).forEach(([attrName, attrValue])=>{
                const normalizedAttrName = attrName.toLowerCase();
                const safeAttr = safeToRemoveAttrs[normalizedAttrName];
                if (helpers_js.isEventHandler(attrName) || safeAttr !== undefined && (safeAttr === null || tagName && safeAttr.includes(tagName))) {
                    if (attrValue === null || attrValue === undefined) {
                        delete newAttrs[attrName];
                    } else if (typeof attrValue === 'string' && attrValue.trim() === '') {
                        delete newAttrs[attrName];
                    }
                }
            });
            return newAttrs;
        };
    }
};

exports.default = mod;