test: verify nested change with context

Related to #20

Author: nikku

test/fixtures/extension-elements/c8-after.bpmn

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<bpmn:definitions 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:zeebe="http://camunda.org/schema/zeebe/1.0" xmlns:modeler="http://camunda.org/schema/modeler/1.0" id="Definitions_1440wfy" targetNamespace="http://bpmn.io/schema/bpmn" exporter="Camunda Modeler" exporterVersion="5.25.0" modeler:executionPlatform="Camunda Cloud" modeler:executionPlatformVersion="8.5.0">
+  <bpmn:process id="PROCESS_1" isExecutable="true">
+    <bpmn:serviceTask id="TASK_1">
+      <bpmn:extensionElements>
+        <zeebe:ioMapping>
+          <zeebe:input source="=FOO" target="FOO_CHANGED" />
+        </zeebe:ioMapping>
+        <zeebe:taskHeaders>
+          <zeebe:header key="FIRST" />
+          <zeebe:header key="SECOND" />
+        </zeebe:taskHeaders>
+      </bpmn:extensionElements>
+    </bpmn:serviceTask>
+  </bpmn:process>
+  <bpmndi:BPMNDiagram id="BPMNDiagram_1">
+    <bpmndi:BPMNPlane id="BPMNPlane_1" bpmnElement="PROCESS_1">
+      <bpmndi:BPMNShape id="TASK_1_di" bpmnElement="TASK_1">
+        <dc:Bounds x="180" y="80" width="100" height="80" />
+      </bpmndi:BPMNShape>
+    </bpmndi:BPMNPlane>
+  </bpmndi:BPMNDiagram>
+</bpmn:definitions>

test/fixtures/extension-elements/c8-before.bpmn

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<bpmn:definitions 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:zeebe="http://camunda.org/schema/zeebe/1.0" xmlns:modeler="http://camunda.org/schema/modeler/1.0" id="Definitions_1440wfy" targetNamespace="http://bpmn.io/schema/bpmn" exporter="Camunda Modeler" exporterVersion="5.25.0" modeler:executionPlatform="Camunda Cloud" modeler:executionPlatformVersion="8.5.0">
+  <bpmn:process id="PROCESS_1" isExecutable="true">
+    <bpmn:serviceTask id="TASK_1">
+      <bpmn:extensionElements>
+        <zeebe:ioMapping>
+          <zeebe:input source="=FOO" target="FOO" />
+        </zeebe:ioMapping>
+        <zeebe:taskHeaders>
+          <zeebe:header key="FIRST" />
+        </zeebe:taskHeaders>
+      </bpmn:extensionElements>
+    </bpmn:serviceTask>
+  </bpmn:process>
+  <bpmndi:BPMNDiagram id="BPMNDiagram_1">
+    <bpmndi:BPMNPlane id="BPMNPlane_1" bpmnElement="PROCESS_1">
+      <bpmndi:BPMNShape id="TASK_1_di" bpmnElement="TASK_1">
+        <dc:Bounds x="180" y="80" width="100" height="80" />
+      </bpmndi:BPMNShape>
+    </bpmndi:BPMNPlane>
+  </bpmndi:BPMNDiagram>
+</bpmn:definitions>

test/spec/differ.js

@@ -317,6 +317,33 @@ describe('diffing', function() {
     });
 
 
+    it('extension elements', function(done) {
+
+      var aDiagram = readFileSync('test/fixtures/extension-elements/c8-before.bpmn', 'utf-8');
+      var bDiagram = readFileSync('test/fixtures/extension-elements/c8-after.bpmn', 'utf-8');
+
+
+      // when
+      testDiff(aDiagram, bDiagram, function(err, results, aDefinitions, bDefinitions) {
+
+        if (err) {
+          return done(err);
+        }
+
+        // TODO(nikku): ensure we provide enough meta-data to be able to
+        //  visualize the actual change
+
+        // then
+        expect(results._added).to.be.empty;
+        expect(results._removed).to.be.empty;
+        expect(results._layoutChanged).to.be.empty;
+        expect(results._changed).to.have.keys([ 'TASK_1' ]);
+
+        done();
+      });
+    });
+
+
     it('pizza collaboration StartEvent move', function(done) {
 
       var aDiagram = readFileSync('test/fixtures/pizza-collaboration/start-event-old.bpmn', 'utf-8');