After modification in Backtesting.py: TypeError: strategy must be a Strategy sub-type

[abderrahim-plb]

Expected Behavior

Hello, I forked the repository, after that i followed the instructions and install it. I tried a first example of an sma strategy, i backtest it using :

bt = Backtest(df,SmaCross,cash=1000,commission=0.0005,margin=0.84,exclusive_orders=True)
output=bt.run()
bt.plot()

If i modify the file backtesting.py even with a simple comment, i am getting the error :

TypeError                                 Traceback (most recent call last)
Cell In[22], line 1
----> 1 bt = Backtest(df,SmaCross,cash=1000,commission=0.0005,margin=0.84,exclusive_orders=True)
      2 output=bt.run()
      3 bt.plot()

File ~/backtesting.py/backtesting/backtesting.py:1082, in Backtest.__init__(self, data, strategy, cash, commission, margin, trade_on_close, hedging, exclusive_orders)
   1035 """
   1036 Initialize a backtest. Requires data and a strategy to test.
   1037 
   (...)
   1078 [FIFO]: https://www.investopedia.com/terms/n/nfa-compliance-rule-2-43b.asp
   1079 """
   1081 if not (isinstance(strategy, type) and issubclass(strategy, Strategy)):
-> 1082     raise TypeError('`strategy` must be a Strategy sub-type')
   1083 if not isinstance(data, pd.DataFrame):
   1084     raise TypeError("`data` must be a pandas.DataFrame with columns")

TypeError: `strategy` must be a Strategy sub-type

---

I should restart the kernel, then everything works fine, but this isn't practical at all.

Actual Behavior

Can't modify in backtesting file, should restart the kernel.

Additional info

• Backtesting version: 0.3.4.dev30+g0ce24d8
• bokeh.__version__: '2.4.3 '
• OS: MAC OS M1

[kernc]

My idea was to simply change the line:

backtesting.py/backtesting/backtesting.py

Line 1081 in 0ce24d8

if not (isinstance(strategy, type) and issubclass(strategy, Strategy)):

to if False: or some such for the duration of development.

Let me know of any other ideas.