NPE when starting Java debugging in IDEA 13.1

I'm getting a NullPointerException when I try to debug a Java process...it doesn't happen all the time though, it might be this particular configuration (which is an individual test in a JUnit test class).

java.lang.NullPointerException
        at com.intellij.debugger.ui.breakpoints.BreakpointManager.addBreakpoint(BreakpointManager.java:590)
        at com.intellij.javascript.debugger.nashorn.NashornJsBreakpointListener.onBreakpointAdded(NashornJsBreakpointListener.java:42)
        at com.intellij.javascript.debugger.nashorn.NashornJsBreakpointListener.<init>(NashornJsBreakpointListener.java:25)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
        at org.picocontainer.defaults.InstantiatingComponentAdapter.newInstance(InstantiatingComponentAdapter.java:193)
        at org.picocontainer.defaults.ConstructorInjectionComponentAdapter$1.run(ConstructorInjectionComponentAdapter.java:220)
        at org.picocontainer.defaults.ThreadLocalCyclicDependencyGuard.observe(ThreadLocalCyclicDependencyGuard.java:53)
        at org.picocontainer.defaults.ConstructorInjectionComponentAdapter.getComponentInstance(ConstructorInjectionComponentAdapter.java:248)
        at org.picocontainer.defaults.DecoratingComponentAdapter.getComponentInstance(DecoratingComponentAdapter.java:60)
        at com.intellij.openapi.components.impl.CachingComponentAdapter.getComponentInstance(CachingComponentAdapter.java:54)
        at com.intellij.openapi.components.impl.ServiceManagerImpl$MyComponentAdapter.initializeInstance(ServiceManagerImpl.java:159)
        at com.intellij.openapi.components.impl.ServiceManagerImpl$MyComponentAdapter$1.compute(ServiceManagerImpl.java:147)
        at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:932)
        at com.intellij.openapi.components.impl.ServiceManagerImpl$MyComponentAdapter.getComponentInstance(ServiceManagerImpl.java:139)
        at com.intellij.util.pico.DefaultPicoContainer.getLocalInstance(DefaultPicoContainer.java:225)
        at com.intellij.util.pico.DefaultPicoContainer.getInstance(DefaultPicoContainer.java:212)
        at com.intellij.util.pico.DefaultPicoContainer.getComponentInstance(DefaultPicoContainer.java:199)
        at org.picocontainer.alternatives.AbstractDelegatingMutablePicoContainer.getComponentInstance(AbstractDelegatingMutablePicoContainer.java:75)
        at com.intellij.openapi.components.ServiceManager.getService(ServiceManager.java:40)
        at com.intellij.javascript.debugger.nashorn.NashornJsBreakpointListener.getInstance(NashornJsBreakpointListener.java:36)
        at com.intellij.javascript.debugger.nashorn.NashornPositionManagerFactory.createPositionManager(NashornPositionManagerFactory.java:93)

        at com.intellij.debugger.impl.DebuggerManagerImpl$3.processAttached(DebuggerManagerImpl.java:241)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:483)
        at com.intellij.util.EventDispatcher.dispatch(EventDispatcher.java:90)
        at com.intellij.util.EventDispatcher.access$100(EventDispatcher.java:34)
        at com.intellij.util.EventDispatcher$1.invoke(EventDispatcher.java:67)
        at com.sun.proxy.$Proxy130.processAttached(Unknown Source)
        at com.intellij.debugger.engine.DebugProcessEvents.e(DebugProcessEvents.java:321)
        at com.intellij.debugger.engine.DebugProcessEvents.commitVM(DebugProcessEvents.java:70)
        at com.intellij.debugger.engine.DebugProcessImpl$9$2$1.action(DebugProcessImpl.java:1831)
        at com.intellij.debugger.engine.events.DebuggerCommandImpl.run(DebuggerCommandImpl.java:45)
        at com.intellij.debugger.engine.DebuggerManagerThreadImpl.processEvent(DebuggerManagerThreadImpl.java:151)
        at com.intellij.debugger.engine.DebuggerManagerThreadImpl.processEvent(DebuggerManagerThreadImpl.java:39)
        at com.intellij.debugger.impl.InvokeThread.a(InvokeThread.java:146)
        at com.intellij.debugger.impl.InvokeThread.access$100(InvokeThread.java:28)
        at com.intellij.debugger.impl.InvokeThread$WorkerThreadRequest.run(InvokeThread.java:55)
        at com.intellij.openapi.application.impl.ApplicationImpl$8.run(ApplicationImpl.java:419)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:744)
        at com.intellij.openapi.application.impl.ApplicationImpl$1$1.run(ApplicationImpl.java:149)

I deleted all my javascript breakpoints and that seemed to stop it happening for now.