TypeError: Invalid NaN comparison calling integrate in sympy 1.12 about sympy

[oscarbenjamin]

This is coming from integrate calling solve which in turn calls checksol. Then we have:

    362         if numerical and val.is_number:
--> 363             return (abs(val.n(18).n(12, chop=True)) < 1e-9) is S.true
    364
    365     if flags.get('warn', False):
    366         warnings.warn("\n\tWarning: could not verify solution %s." % sol)
    367     # returns None if it can't conclude
    368     # TODO: improve solution testing
    369

ipdb> p val
nan
ipdb> p val.is_number
True

I wonder if nan.is_number should actually be False. The internal call to solve is:

In [7]: solve([b**x*log(a) - b**x*log(b)], exclude=(x,))
---------------------------------------------------------------------------
TypeError