# Incorrect result for integral of (cos z) / z

I am confused by the following result: I'd like to integrate `cos(z) / z`

on a circle around the origin. I tried:

```
var('z,t')
f = (cos(z))/z
show(f)
gamma = e^(i * t)
dg = gamma.diff(t)
h = f(z=gamma) * dg
print(h)
show(h.integrate(t, 0, 2 * pi))
```

and I get:

```
I*cos(e^(I*t))
0
```

If I put the same integral into WolframAlpha, I get the result I was expecting (`2 pi i`

).

Is this a bug, or have I specified the problem incorrectly?