https://www.dctrust.ie/common/js/forms/fields/icons/RevealIcon.js?v=254

1; (function (root, factory) {
2    const ns = root.FieldKit = root.FieldKit || {};
3    ns.icons = ns.icons || {};
4    factory(ns);
5})(window, function (FieldKit) {
6    const icons = FieldKit.icons;
7    const { BaseIcon } = icons;
8
9    class RevealIcon extends BaseIcon {
10        render() {
11            const button = document.createElement('button');
12            button.type = 'button';
13            button.className = 'field__action field__action--reveal';
14            button.setAttribute('aria-label', 'Show password');
15            button.setAttribute('aria-pressed', 'false');
16            button.innerHTML = '<i class="fa fa-eye-slash"></i>';
17            return button;
18        }
19
20        bind() {
21            this.element.addEventListener('click', () => {
22                const shown = this.host.element.type === 'text';
23                this.host.element.type = shown ? 'password' : 'text';
24
25                // glyph swap
26                this.element.querySelector('i').className = `fa fa-${shown ? 'eye-slash' : 'eye'}`;
27
28                // accessibility
29                this.element.setAttribute('aria-pressed', String(!shown));
30                this.element.setAttribute(
31                    'aria-label',
32                    shown ? 'Show password' : 'Hide password',
33                );
34            });
35        }
36    }
37
38    // Namespace export
39    icons.RevealIcon = RevealIcon;
40});