fix(bpmn-updater): keep conditions on element replace

Closes camunda/camunda-modeler#318

lib/features/modeling/BpmnUpdater.js

@@ -199,21 +199,25 @@ function BpmnUpdater(eventBus, bpmnFactory, connectionDocking, translate) {
     if ((businessObject.sourceRef && businessObject.sourceRef.default) &&
         !(is(newTarget, 'bpmn:Activity') ||
           is(newTarget, 'bpmn:EndEvent') ||
+          is(newTarget, 'bpmn:Gateway') ||
           is(newTarget, 'bpmn:IntermediateThrowEvent')) ) {
       context.default = businessObject.sourceRef.default;
       businessObject.sourceRef.default = undefined;
     }
 
     // on reconnectStart -> conditional flow
-    if ((businessObject.conditionExpression) && !is(newSource, 'bpmn:Activity')) {
+    if (oldSource && (businessObject.conditionExpression) &&
+      !(is(newSource, 'bpmn:Activity') ||
+        is(newSource, 'bpmn:Gateway')) ) {
       context.conditionExpression = businessObject.conditionExpression;
       businessObject.conditionExpression = undefined;
     }
 
     // on reconnectEnd -> conditional flow
-    if ((businessObject.conditionExpression) &&
+    if (oldTarget && (businessObject.conditionExpression) &&
         !(is(newTarget, 'bpmn:Activity') ||
           is(newTarget, 'bpmn:EndEvent') ||
+          is(newTarget, 'bpmn:Gateway') ||
           is(newTarget, 'bpmn:IntermediateThrowEvent')) ) {
       context.conditionExpression = businessObject.conditionExpression;
       businessObject.conditionExpression = undefined;

test/spec/features/modeling/UpdatePropertiesSpec.js

@@ -88,6 +88,47 @@ describe('features/modeling - update properties', function() {
     }));
 
 
+    it('updating conditional flow on source replace', inject(function(bpmnReplace, elementRegistry) {
+
+      //given
+      var conditionalFlow = elementRegistry.get('SequenceFlow_3'),
+          serviceTask = elementRegistry.get('ServiceTask_1');
+
+      var conditionExpression = conditionalFlow.businessObject.conditionExpression;
+
+      var userTaskData =  {
+        type: 'bpmn:UserTask'
+      };
+
+      // when
+      bpmnReplace.replaceElement(serviceTask, userTaskData);
+
+      // then
+      expect(conditionalFlow.businessObject.conditionExpression).to.eql(conditionExpression);
+    }));
+
+
+    it('updating conditional flow on target replace', inject(function(bpmnReplace, elementRegistry) {
+
+      //given
+      var conditionalFlow = elementRegistry.get('SequenceFlow_3'),
+          endEvent = elementRegistry.get('EndEvent_1');
+
+      var conditionExpression = conditionalFlow.businessObject.conditionExpression;
+
+      var messageEndEventData =  {
+        type: 'bpmn:EndEvent',
+        eventDefinitionType: 'bpmn:MessageEventDefinition'
+      };
+
+      // when
+      bpmnReplace.replaceElement(endEvent, messageEndEventData);
+
+      // then
+      expect(conditionalFlow.businessObject.conditionExpression).to.eql(conditionExpression);
+    }));
+
+
     it('setting name', inject(function(elementRegistry, modeling) {
 
       // given