#5681 integrate(tan(x),x,0,%pi/4) and limit(log(cos(x)),x,%pi/4) signal an error

[David Scherfgen]

integrate(tan(x),x,0,%pi/4) signals an error instead of returning log(2)/2:

(%i1) display2d:false$
(%i2) integrate(tan(x),x,0,%pi/4);
asec: argument 0 isn't in the domain of asec.
limit: second argument must be a variable, not a constant; found: zeroa
 -- an error. To debug this try: debugmode(true);

The error comes from limit(), which fails the same way for log(cos(x)) at %pi/4:

(%i3) limit(log(cos(x)),x,%pi/4,minus);
limit: second argument must be a variable, not a constant; found: zeroa
 -- an error. To debug this try: debugmode(true);

The expected result is -log(2)/2. Other limits fail too, for example limit(log(cos(x)),x,%pi/3,plus), limit(log(sin(x)),x,%pi/4,plus) and the two-sided limit(log(cos(x)),x,%pi/4). Maxima 5.50.0 gets all of these right, so this is a regression in the development version.

[David Scherfgen]

Fixed by commit [5faac59].