Crash switching variables on set statements (NPE)

[plattysoft]

I have seen this crash at least 3 times and it is quite replicable, but not 100%

Steps to replicate:

• Add 2 set {variable} to {value} pieces
• Swap the variable name of one
• Swap the variable name of the other

Not sure if there needs to be more than 3 variables, if the other pieces on the workspace are relevant, or if they need to be connected, but each time I've tried to build a relatively complex program involving 3 variables it has crashed at some point.

Something like this is what I was trying to write:

position = 0
increasing = false

if (increasing) {
   position = position +1
   if (position == max) {
      increasing = false
   }
}
else {
   position = position -1
   if (position == min) {
      increasing = true
   }
}

This is the stack trace I am getting:

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean com.google.blockly.android.control.WorkspaceStats$VariableInfoImpl.removeField(com.google.blockly.model.FieldVariable)' on a null object reference
at com.google.blockly.android.control.WorkspaceStats$1.onValueChanged(WorkspaceStats.java:52)
at com.google.blockly.model.Field$1.run(Field.java:240)
at com.google.blockly.model.Block.runAsPossibleEventGroup(Block.java:1318)
at com.google.blockly.model.Field.runAsPossibleEventGroup(Field.java:252)
at com.google.blockly.model.Field.fireValueChanged(Field.java:232)
at com.google.blockly.model.FieldVariable.setVariable(FieldVariable.java:74)
at com.google.blockly.android.ui.fieldview.BasicFieldVariableView.setSelection(BasicFieldVariableView.java:116)
at android.widget.Spinner$DropdownPopup$1.onItemClick(Spinner.java:1186)
at android.widget.AdapterView.performItemClick(AdapterView.java:318)
at android.widget.AbsListView.performItemClick(AbsListView.java:1158)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:3127)
at android.widget.AbsListView$3.run(AbsListView.java:4042)
at android.os.Handler.handleCallback(Handler.java:790)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
01-01 00:37:43.678 3437-3437/com.plattysoft.blocklyrainbowhat I/Process: Sending signal. PID: 3437 SIG: 9