Implement copying and add test

Author: timKraeuter

lib/features/modeling/behavior/CreateDataObjectBehavior.js

@@ -29,6 +29,9 @@ export default function CreateDataObjectBehavior(eventBus, bpmnFactory) {
       // create a DataObject every time a DataObjectReference is created
       var dataObject = bpmnFactory.create('bpmn:DataObject');
 
+      // Copy the isCollection property if needed.
+      dataObject.isCollection = shape.businessObject.dataObjectRef?.isCollection || false;
+
       // set the reference to the DataObject
       shape.businessObject.dataObjectRef = dataObject;
     }

test/spec/features/modeling/behavior/DataObjectBehaviorSpec.js

@@ -45,6 +45,32 @@ describe('features/modeling/behavior - data object', function() {
     }));
 
 
+    it('should copy the isCollection property in DataObject if present', inject(function(modeling, copyPaste) {
+
+      // when
+      var dataObjectRefShape = modeling.createShape({ type: 'bpmn:DataObjectReference' },
+        { x: 220, y: 220 }, rootShape);
+      dataObjectRefShape.businessObject.dataObjectRef.isCollection = true;
+
+      copyPaste.copy(dataObjectRefShape);
+      var pastedElements = copyPaste.paste({
+        element: rootShape,
+        point: {
+          x: 350,
+          y: 150
+        }
+      });
+
+      var dataObject = pastedElements[0].businessObject.dataObjectRef;
+
+      // then
+      expect(dataObject).to.exist;
+      expect(is(dataObject, 'bpmn:DataObject')).to.be.true;
+      expect(dataObject.id).to.exist;
+      expect(dataObject.isCollection).to.be.true;
+    }));
+
+
     it('should create the corresponding DataObject / undo');