NullPointerException while checking referenced DMN when data flow analysis is enabled

[redfave]

Describe the bug
When executing a test run with enabled data flow analysis on a BPMN model referencing a DMN file, the test fails with a NullPointerException.

SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

java.lang.NullPointerException
	at de.viadee.bpm.vPAV.processing.BpmnModelDispatcher.dispatchWithVariables(BpmnModelDispatcher.java:91)
	at de.viadee.bpm.vPAV.Runner.checkModel(Runner.java:566)
	at de.viadee.bpm.vPAV.Runner.checkModels(Runner.java:534)
	at de.viadee.bpm.vPAV.Runner.createIssues(Runner.java:246)
	at de.viadee.bpm.vPAV.Runner.viadeeProcessApplicationValidator(Runner.java:102)
	at de.viadee.bpm.vPAV.ProcessApplicationValidator.createRunner(ProcessApplicationValidator.java:138)
	at de.viadee.bpm.vPAV.ProcessApplicationValidator.findModelInconsistencies(ProcessApplicationValidator.java:73)
	at ModelConsistencyTest.validateModel(ModelConsistencyTest.java:19)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:564)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
	at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
	at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230)
	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)

A possible workaround is to disable any data flow analysis related features in the ruleSet.xml. It seems that input variables inside the DMN file are causing trouble.