What modifies Ext.data.GroupingStore "lastOptions" property?

[ar6]

Hi,

I am using a GroupingStore in my application and the property "lastOptions" is giving me a fit. I could not understand what it is used for using the API documentation so a simpler explanation will surely help.
How and when does it get modified?
When I do groupingStore.load() , the lastOptions gets some value and is no longer null. However, on doing groupingStore.loadData(someJsonData) , the lastOptions value is not set and returns "null". Is this expected behavior or a bug? How can i cause lastOptions to be modified on calling loadData()?

[mitchellsimoens]

The load method of Ext.data.Store when it executes the storeOptions method.

[ar6]

Thanks Mitchell..bt does the loadData() method also do the same??
I have a case where lastOptions is not being set on loading data by calling store.loadData(mydata) and so want to know if this is expected behavior or a bug

[mitchellsimoens]

You don't have options when you use loadData. You are basically just inserting data.