test: cover case when there are no functions

Author: theburningmonk

lib/deploy/stepFunctions/compileStateMachines.test.js

@@ -975,5 +975,53 @@ describe('#compileStateMachines', () => {
       expect(definition.States.Lambda2.Resource)
         .to.equal('arn:aws:lambda:us-east-1:1234567890:function:world');
     });
+
+    it('should do nothing if there are no ref to lambda functions, even if useExactVersion is true', () => {
+      serverless.service.stepFunctions = {
+        stateMachines: {
+          myStateMachine1: {
+            id: 'Test',
+            useExactVersion: true,
+            definition: {
+              StartAt: 'Sns',
+              States: {
+                Sns: {
+                  Type: 'Task',
+                  Resource: 'arn:aws:states:::sns:publish',
+                  Parameters: {
+                    Message: {
+                      'Fn::GetAtt': ['MyTopic', 'TopicName'],
+                    },
+                    TopicArn: {
+                      Ref: 'MyTopic',
+                    },
+                  },
+                  End: true,
+                },
+              },
+            },
+          },
+        },
+      };
+
+      serverlessStepFunctions.compileStateMachines();
+      const stateMachine = serverlessStepFunctions.serverless.service
+        .provider.compiledCloudFormationTemplate.Resources
+        .Test;
+
+      expect(stateMachine.Properties.DefinitionString).to.haveOwnProperty('Fn::Sub');
+      expect(stateMachine.Properties.DefinitionString['Fn::Sub']).to.have.lengthOf(2);
+
+      const [json, params] = stateMachine.Properties.DefinitionString['Fn::Sub'];
+      const modifiedDefinition = JSON.parse(json);
+
+      const sns = modifiedDefinition.States.Sns;
+      expect(sns.Parameters.TopicArn.startsWith('${')).to.eq(true);
+      const topicArnParam = sns.Parameters.TopicArn.replace(/[${}]/g, '');
+      expect(params).to.haveOwnProperty(topicArnParam);
+      const topicArn = params[topicArnParam];
+
+      expect(topicArn).to.deep.equal({ Ref: 'MyTopic' });
+    });
   });
 });