fix: ignore invalid event definition reference (#3018)

Previously, the parser assumed that the identifier reference in the
event definition was valid, i.e. that the identifier was defined at the
top level.
If this was not the case, the corresponding event definition was not
retrieved. The following code attempted to access properties with
undefined values.
This generated an error.
The parser now ignores the invalid reference and set the event definition
to the default value (none).

src/component/parser/json/converter/ProcessConverter.ts

@@ -339,7 +339,7 @@ export default class ProcessConverter {
 
     for (const eventDefinitionReference of ensureIsArray<string>(bpmnElement.eventDefinitionRef)) {
       const eventDefinition = this.convertedElements.findEventDefinitionOfDefinition(eventDefinitionReference);
-      eventDefinitionsByKind.get(eventDefinition.kind).push(eventDefinition);
+      eventDefinition && eventDefinitionsByKind.get(eventDefinition.kind).push(eventDefinition);
     }
 
     for (const [kind] of [...eventDefinitionsByKind.entries()].filter(([, registeredEventDefinitions]) => registeredEventDefinitions.length === 0)) {

test/fixtures/bpmn/model-invalid-event-def-ref.bpmn

@@ -0,0 +1,44 @@
+<bpmn:definitions xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:bpmn="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:dc="http://www.omg.org/spec/DD/20100524/DC" xmlns:di="http://www.omg.org/spec/DD/20100524/DI" id="Definitions_0x0opj6" targetNamespace="http://example.bpmn.com/schema/bpmn">
+<bpmn:process id="Process_1" isExecutable="false">
+  <bpmn:startEvent id="StartEvent_1" name="Start Event with invalid event definition reference">
+    <bpmn:eventDefinitionRef>top_message_definition_id_invalid_reference</bpmn:eventDefinitionRef>
+    <bpmn:outgoing>Flow_1</bpmn:outgoing>
+  </bpmn:startEvent>
+  <bpmn:sequenceFlow id="Flow_1" sourceRef="StartEvent_1" targetRef="Activity_1" name="Sequence Flow 1" />
+  <bpmn:task id="Activity_1" name="Task 1">
+    <bpmn:incoming>Flow_1</bpmn:incoming>
+    <bpmn:outgoing>Flow_2</bpmn:outgoing>
+  </bpmn:task>
+  <bpmn:endEvent id="EndEvent_1" name="End Event 1">
+    <bpmn:incoming>Flow_2</bpmn:incoming>
+  </bpmn:endEvent>
+  <bpmn:sequenceFlow id="Flow_2" sourceRef="Activity_1" targetRef="EndEvent_1" />
+</bpmn:process>
+<bpmndi:BPMNDiagram id="BPMNDiagram_1">
+  <bpmndi:BPMNPlane id="BPMNPlane_1" bpmnElement="Process_1">
+    <bpmndi:BPMNEdge id="BPMNEdge_Flow_1" bpmnElement="Flow_1">
+      <di:waypoint x="192" y="99" />
+      <di:waypoint x="250" y="99" />
+    </bpmndi:BPMNEdge>
+    <bpmndi:BPMNEdge id="BPMNEdge_Flow_2" bpmnElement="Flow_2">
+      <di:waypoint x="350" y="99" />
+      <di:waypoint x="412" y="99" />
+    </bpmndi:BPMNEdge>
+    <bpmndi:BPMNShape id="BPMNShape_StartEvent_1" bpmnElement="StartEvent_1">
+      <dc:Bounds x="156" y="81" width="36" height="36" />
+      <bpmndi:BPMNLabel>
+        <dc:Bounds x="158" y="124" width="33" height="14" />
+      </bpmndi:BPMNLabel>
+    </bpmndi:BPMNShape>
+    <bpmndi:BPMNShape id="BPMNShape_Activity_1" bpmnElement="Activity_1">
+      <dc:Bounds x="250" y="59" width="100" height="80" />
+    </bpmndi:BPMNShape>
+    <bpmndi:BPMNShape id="BPMNShape_EndEvent_1" bpmnElement="EndEvent_1">
+      <dc:Bounds x="412" y="81" width="36" height="36" />
+      <bpmndi:BPMNLabel>
+        <dc:Bounds x="416" y="124" width="29" height="14" />
+      </bpmndi:BPMNLabel>
+    </bpmndi:BPMNShape>
+  </bpmndi:BPMNPlane>
+</bpmndi:BPMNDiagram>
+</bpmn:definitions>

test/integration/model.elements.api.test.ts

@@ -229,6 +229,24 @@ describe('Registry API - retrieve Model Bpmn elements', () => {
     });
   });
 
+  describe('Get by ids - invalid references in diagram', () => {
+    test('Invalid event definition reference', () => {
+      const bpmnElementsRegistry = bpmnVisualization.bpmnElementsRegistry;
+
+      bpmnVisualization.load(readFileSync('../fixtures/bpmn/model-invalid-event-def-ref.bpmn'));
+      const modelElements = bpmnElementsRegistry.getModelElementsByIds('StartEvent_1');
+
+      expect(modelElements).toHaveLength(1);
+      expectStartEvent(modelElements[0] as ShapeBpmnSemantic, {
+        eventDefinitionKind: ShapeBpmnEventDefinitionKind.NONE, // no event definition reference, so use default
+        id: 'StartEvent_1',
+        name: 'Start Event with invalid event definition reference',
+        outgoing: ['Flow_1'],
+        parentId: undefined,
+      });
+    });
+  });
+
   describe('Get by kinds', () => {
     const bv = initializeBpmnVisualization(null);
     const bpmnElementsRegistry = bv.bpmnElementsRegistry;