fix: always return variables context in getResultContext

Author: barmac

CHANGELOG.md

@@ -6,6 +6,10 @@ All notable changes to [@bpmn-io/variable-resolver](https://github.com/bpmn-io/v
 
 ___Note:__ Yet to be released changes appear here._
 
+## 1.3.6
+
+* `FIX`: always return an instance of variables context in `getResultContext` ([#58](https://github.com/bpmn-io/variable-resolver/pull/58))
+
 ## 1.3.5
 
 * `FIX`: do not try to find unresolved variables of a broken expression ([#50](https://github.com/bpmn-io/variable-resolver/issues/50))

lib/zeebe/util/feelUtility.js

@@ -129,7 +129,7 @@ export function getResultContext(expression, variables = {}) {
 
   // This is a hack to get the latest variables from the context tracker
   // lezer does not automatically annotate the parse tree with the context
-  let latestVariables = null;
+  let latestVariables = contextTracker.start;
 
   const customContextTracker = new ContextTracker({
     start: contextTracker.start,

test/fixtures/zeebe/immediately-broken-expression.bpmn

@@ -0,0 +1,32 @@
+<?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:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:bioc="http://bpmn.io/schema/bpmn/biocolor/1.0" xmlns:color="http://www.omg.org/spec/BPMN/non-normative/color/1.0" xmlns:di="http://www.omg.org/spec/DD/20100524/DI" xmlns:modeler="http://camunda.org/schema/modeler/1.0" id="Definitions_1" targetNamespace="http://bpmn.io/schema/bpmn" exporter="Camunda Modeler" exporterVersion="5.39.0" modeler:executionPlatform="Camunda Cloud" modeler:executionPlatformVersion="8.8.0">
+  <bpmn:process id="Process_0j5qzil" name="Agent Blueprint (Long Term Memory)" isExecutable="true">
+    <bpmn:serviceTask id="Task_1" name="Handle customer request">
+      <bpmn:outgoing>Flow_1imcl82</bpmn:outgoing>
+    </bpmn:serviceTask>
+    <bpmn:sequenceFlow id="Flow_1imcl82" sourceRef="Task_1" targetRef="Task_2" />
+    <bpmn:serviceTask id="Task_2">
+      <bpmn:extensionElements>
+        <zeebe:ioMapping>
+          <zeebe:input source="=..." target="target" />
+        </zeebe:ioMapping>
+      </bpmn:extensionElements>
+      <bpmn:incoming>Flow_1imcl82</bpmn:incoming>
+    </bpmn:serviceTask>
+  </bpmn:process>
+  <bpmndi:BPMNDiagram id="BPMNDiagram_1">
+    <bpmndi:BPMNPlane id="BPMNPlane_1" bpmnElement="Process_0j5qzil">
+      <bpmndi:BPMNShape id="Activity_1clcfsu_di" bpmnElement="Task_1" bioc:stroke="#0d4372" bioc:fill="#bbdefb" color:background-color="#bbdefb" color:border-color="#0d4372">
+        <dc:Bounds x="153" y="80" width="100" height="80" />
+        <bpmndi:BPMNLabel />
+      </bpmndi:BPMNShape>
+      <bpmndi:BPMNShape id="Activity_1a52niu_di" bpmnElement="Task_2">
+        <dc:Bounds x="340" y="80" width="100" height="80" />
+      </bpmndi:BPMNShape>
+      <bpmndi:BPMNEdge id="BPMNEdge_06wqta8" bpmnElement="Flow_1imcl82">
+        <di:waypoint x="253" y="120" />
+        <di:waypoint x="340" y="120" />
+      </bpmndi:BPMNEdge>
+    </bpmndi:BPMNPlane>
+  </bpmndi:BPMNDiagram>
+</bpmn:definitions>

test/spec/zeebe/ZeebeVariableResolver.spec.js

@@ -14,6 +14,7 @@ import complexXML from 'test/fixtures/zeebe/complex.bpmn';
 import connectorsXML from 'test/fixtures/zeebe/connectors.bpmn';
 import ioMappingsXML from 'test/fixtures/zeebe/ioMappings.bpmn';
 import longBrokenExpressionXML from 'test/fixtures/zeebe/long-broken-expression.bpmn';
+import immediatelyBrokenExpressionXML from 'test/fixtures/zeebe/immediately-broken-expression.bpmn';
 
 import VariableProvider from 'lib/VariableProvider';
 import { getInputOutput } from '../../../lib/base/util/ExtensionElementsUtil';
@@ -1043,32 +1044,65 @@ describe('ZeebeVariableResolver', function() {
 
   describe('parsing', function() {
 
-    beforeEach(bootstrapModeler(longBrokenExpressionXML, {
-      container,
-      additionalModules: [
-        ZeebeVariableResolverModule
-      ],
-      moddleExtensions: {
-        zeebe: ZeebeModdle
-      }
-    }));
+    describe('long broken expression', function() {
 
+      beforeEach(bootstrapModeler(longBrokenExpressionXML, {
+        container,
+        additionalModules: [
+          ZeebeVariableResolverModule
+        ],
+        moddleExtensions: {
+          zeebe: ZeebeModdle
+        }
+      }));
 
-    it('should NOT error on a long broken expression', inject(async function(elementRegistry, variableResolver) {
 
-      // given
-      const task = elementRegistry.get('Task_1');
-      const bo = getBusinessObject(task);
-      const input = getInputOutput(bo).inputParameters[1];
+      it('should NOT error on a long broken expression', inject(async function(elementRegistry, variableResolver) {
 
-      // when
-      const variables = await variableResolver.getVariablesForElement(bo, input);
+        // given
+        const task = elementRegistry.get('Task_1');
+        const bo = getBusinessObject(task);
 
-      // then
-      expect(variables).to.variableEqual([
-        { name: 'target' }
-      ]);
-    }));
+        // when
+        const variables = await variableResolver.getVariablesForElement(bo);
+
+        // then
+        expect(variables).to.variableEqual([
+          { name: 'target' }
+        ]);
+      }));
+
+    });
+
+
+    describe('immediately broken expression', function() {
+
+      beforeEach(bootstrapModeler(immediatelyBrokenExpressionXML, {
+        container,
+        additionalModules: [
+          ZeebeVariableResolverModule
+        ],
+        moddleExtensions: {
+          zeebe: ZeebeModdle
+        }
+      }));
+
+
+      it('should NOT error on an immediate syntax error', inject(async function(elementRegistry, variableResolver) {
+
+        // given
+        const task = elementRegistry.get('Task_2');
+        const bo = getBusinessObject(task);
+
+        // when
+        const variables = await variableResolver.getVariablesForElement(bo);
+
+        // then
+        expect(variables).to.variableEqual([
+          { name: 'target' }
+        ]);
+      }));
+    });
   });
 
 });