#NEWLINE# def test_immutable_during_iteration( self ) : #NEWLINE# #INDENT# it = self . it #NEWLINE# self . assertEqual ( len ( it ) , n ) #NEWLINE# next ( self ) #NEWLINE# self . assertEqual ( len ( it ) , ( n - 1 ) ) #NEWLINE# self . mutate ( ) #NEWLINE# self . assertRaises ( RuntimeError , next , it ) #NEWLINE# self . assertEqual ( len ( it ) , 0 )