Possible bug when using LinePlotterIndicator

[Rubén Briones]

When I use the bt.LinePlotterIndicator the Strategy starts executing later than the period defined in params. I think that when we add the bt.LinePlotterIndicator, backtrader multiply by 2 the bars needed to start executing the strategy.

My code is:

class SMACloseSignal(bt.SignalStrategy):
    params = (('period', 30),)

    def __init__(self):
        signal = bt.indicators.CrossOver(self.data, bt.indicators.SMA(period=self.p.period))
        self.signal_add(bt.SIGNAL_LONG, signal)

        signal_to_plot = self.data - bt.indicators.SMA(period=self.p.period)
        bt.LinePlotterIndicator(signal_to_plot, name='SMAsignal')