public void Remove()
{
var maskedTextProvider = new MaskedTextProvider(TestSimpleDigitMask);
Assert.True(maskedTextProvider.InsertAt("1", 0));
Assert.Equal(1, maskedTextProvider.AssignedEditPositionCount);
Assert.True(maskedTextProvider.Remove());
Assert.Equal(0, maskedTextProvider.AssignedEditPositionCount);
}