In version 4.2.6 of Bryntum Gantt if I try to load a project that has 1 (or more) task(s) with a start date but no end date I see the following error:
TypeError: Cannot read property 'getTime' of null
at Function.max (/Users/brittanythompson/workspace/gantt/lib/gantt/lib/Core/helper/DateHelper.js:2110:22)
at Gantt.param [as internalOnProjectRefresh] (/Users/brittanythompson/workspace/gantt/lib/gantt/lib/Gantt/view/mixin/GanttStores.js:136:51)
I was also able to see the same error with this jest test (the error occurs when project.commitAsync is called):
import Gantt from '../../lib/gantt/lib/Gantt/view/Gantt'
import ProjectModel from '../../lib/gantt/lib/Gantt/model/ProjectModel'
test('can load a project with no end date', async () => {
const project = new ProjectModel();
await project.loadInlineData({tasksData: [{id: 1, startDate: '2020-02-02'}]});
const gantt = new Gantt({project});
gantt.project.taskStore.getById(1).name = 'hello there'
await gantt.project.commitAsync();
expect(gantt.project.taskStore.getById(1).name).toEqual('hello there');
});