Exception thrown when loading data into individual stores with `loadDataAsync`

[canonic-epicure]

Forum post

Steps to reproduce:

• Replace Gantt/examples/basic/app.js with:

  
  import '../_shared/shared.js'; // not required, our example styling etc.
  import Gantt from '../../lib/Gantt/view/Gantt.js';
  import TaskStore from '../../lib/Gantt/data/TaskStore.js';
  import ProjectModel from '../../lib/Gantt/model/ProjectModel.js';
  import ResourceAssignmentColumn from '../../lib/Gantt/column/ResourceAssignmentColumn.js';
  import '../../lib/Gantt/column/AllColumns.js';
  import ColumnStore from '../../lib/Grid/data/ColumnStore.js';
  import StringHelper from '../../lib/Core/helper/StringHelper.js';

const resources = [ { id : 1, name : 'Celia', city : 'Barcelona', calendar : null, image : 'celia.jpg' } ]; const taskData = [ { id : 1000, name : 'Launch SaaS Product', percentDone : 34, startDate : '2019-01-14', endDate : '2019-03-20', duration : 47, expanded : false, complexity : 3, children : [] } ];

const assignmentData = [ { id : 1, event : 11, resource : 1 } ];

class GNT_TaskStore extends TaskStore { static get type() { return 'gnt_taskstore'; }

static get configurable() {
    return {
        // transformFlatData : true
    };
}

}

GNT_TaskStore.initClass();

class GNT_ResourceAssignmentColumn extends ResourceAssignmentColumn { static get $name() { return 'GNT_ResourceAssignmentColumn'; }

static get type() {
    return 'gnt_resourceassignment';
}

}

ColumnStore.registerColumnType(GNT_ResourceAssignmentColumn);

const project = new ProjectModel({ taskStoreClass : GNT_TaskStore });

const gantt = new Gantt({ appendTo : 'container', dependencyIdField : 'sequenceNumber', rowHeight : 45, tickSize : 45, barMargin : 8, project,

columns : [
    { type : 'name', width : 250 },
    { type : 'startdate' },
    { type : 'enddate' },
    { type : 'gnt_resourceassignment' }
],

// Custom task content, display task name on child tasks
taskRenderer({ taskRecord }) {
    if (taskRecord.isLeaf && !taskRecord.isMilestone) {
        return StringHelper.encodeHtml(taskRecord.name);
    }
},

tbar : {
    items : [
        {
            type : 'button',
            text : 'Load Data',
            async onAction() {
                await Promise.all([
                    gantt.project.taskStore.loadDataAsync(taskData),
                    gantt.project.assignmentStore.loadDataAsync(assignmentData),
                    gantt.project.resourceStore.loadDataAsync(resources),
                ]);
            }
        }
    ]
}

});

- open the `basic` gantt example
- click `Load data` button the toolbar twice
- Observe the exception in console on 2nd click