feat(label-editing): create categoryValue if not exist

Relates to #955

lib/features/label-editing/LabelEditingProvider.js

@@ -6,7 +6,15 @@ import {
   getLabel
 } from './LabelUtil';
 
-import { is } from '../../util/ModelUtil';
+import {
+  getBusinessObject,
+  is
+} from '../../util/ModelUtil';
+
+import {
+  createCategoryValue
+} from '../modeling/behavior/util/CategoryUtil';
+
 import { isAny } from '../modeling/util/ModelingUtil';
 import { isExpanded } from '../../util/DiUtil';
 
@@ -19,9 +27,10 @@ import {
 
 
 export default function LabelEditingProvider(
-    eventBus, canvas, directEditing,
+    eventBus, bpmnFactory, canvas, directEditing,
     modeling, resizeHandles, textRenderer) {
 
+  this._bpmnFactory = bpmnFactory;
   this._canvas = canvas;
   this._modeling = modeling;
   this._textRenderer = textRenderer;
@@ -102,6 +111,7 @@ export default function LabelEditingProvider(
 
 LabelEditingProvider.$inject = [
   'eventBus',
+  'bpmnFactory',
   'canvas',
   'directEditing',
   'modeling',
@@ -370,6 +380,23 @@ LabelEditingProvider.prototype.update = function(
     };
   }
 
+  if (is(element, 'bpmn:Group')) {
+
+    var businessObject = getBusinessObject(element);
+
+    // initialize categoryValue if not existing
+    if (!businessObject.categoryValueRef) {
+
+      var rootElement = this._canvas.getRootElement(),
+          definitions = getBusinessObject(rootElement).$parent;
+
+      var categoryValue = createCategoryValue(definitions, this._bpmnFactory);
+
+      getBusinessObject(element).categoryValueRef = categoryValue;
+    }
+
+  }
+
   if (isEmptyText(newLabel)) {
     newLabel = null;
   }

test/spec/features/label-editing/LabelEditingProviderSpec.js

@@ -421,6 +421,38 @@ describe('features - label-editing', function() {
   });
 
 
+  describe('group support', function() {
+
+    beforeEach(bootstrapModeler(diagramXML, {
+      modules: [
+        labelEditingModule,
+        coreModule,
+        modelingModule
+      ],
+      canvas: { deferUpdate: false }
+    }));
+
+    it('should initialize categoryValue for empty group', inject(
+      function(elementRegistry, directEditing) {
+
+        // given
+        var shape = elementRegistry.get('Group_2');
+
+        // when
+        directEditing.activate(shape);
+        directEditing._textbox.content.innerText = 'FOO';
+        directEditing.complete();
+
+        // then
+        var label = getLabel(shape);
+
+        expect(shape.businessObject.categoryValueRef).to.exist;
+        expect(label).to.equal('FOO');
+      }
+    ));
+
+  });
+
   describe('sizes', function() {
 
     beforeEach(bootstrapModeler(diagramXML, {