Is this a memory leak?

[jbphet]

During the code review, @samreid and I came across the following code, and neither of us was sure whether or not it would cause a memory leaks, since there is no explicit unlink. We should create a test and figure this out. I'm thinking that it is probably fine because the reference to the traveling action potential is eventually released, but it would be good to be certain.

initiateTravelingActionPotential: function() {
        var thisAxonMembrane = this;
        this.travelingActionPotential = new TravelingActionPotential( this );
        this.travelingActionPotential.crossSectionReachedProperty.lazyLink( function( reached ) {
          if ( reached ) {
            thisAxonMembrane.travelingActionPotentialReachedCrossSection = true;
          }
        } );

        this.travelingActionPotential.lingeringCompletedProperty.lazyLink( function( lingeringCompleted ) {
          if ( lingeringCompleted ) {
            thisAxonMembrane.removeTravelingActionPotential();
          }
        } );

        thisAxonMembrane.travelingActionPotentialStarted = true;
        thisAxonMembrane.travelingActionPotentialEnded = false;
        thisAxonMembrane.travelingActionPotentialReachedCrossSection = false;
      },

[samreid]

@AshrafSharf can you take a look and give your thoughts?

[jbphet]

I ran several memory profiling tests and reviewed the code, and am reasonably certain that this is not a memory leak. Other than code inspection, I did the following, all of which is good to do in order to verify that there are no memory leaks:

• profiled using the "Timeline" in Chrome, and determined that the memory low point, which occurs each time a new action potential is initiated (because the previously recorded data is dumped at that point and the chart is cleared) returns to the same base level
• captured heap snapshots and determined that the number of allocated instances of TravelingActionPotential, TravelingActionPotentialNode, and closures are not increasing
• verified that when the membrane potential chart is cleared after an action potential, the total size of the heap snapshot does not increase (at least not significantly)

So, I think it's save to answer the title with a "no" and close the issue.