chill-bundles/docs/source/development/user-interface/js-functions/show_hide.js

import { ShowHide } from 'ShowHide/show_hide.js';

var 
    div_accompagnement = document.getElementById("form_accompagnement"),
    div_accompagnement_comment = document.getElementById("form_accompagnement_comment"),
    div_caf_id = document.getElementById("cafId"),
    div_caf_inscription_date = document.getElementById("cafInscriptionDate"),
    ;

// let show/hide the div_accompagnement_comment if the input with value `'autre'` is checked
new ShowHide({
    "froms": [div_accompagnement],
    "test": function(froms, event) { 
        for (let el of froms.values()) {
            for (let input of el.querySelectorAll('input').values()) {
                if (input.value === 'autre') {
                    return input.checked;
                }
            }
        }
        
        return false;
    },
    "container": [div_accompagnement_comment]
});

// let show the date input only if the the id is filled 
new ShowHide({
    froms: [ div_caf_id ],
    test: function(froms, event) {
        for (let el of froms.values()) {
            return el.querySelector("input").value !== "";
        }
    },
    container: [ div_caf_inscription_date ],
    // using this option, we use the event `input` instead of `change`
    event_name: 'input'
});