When dumped into a text file by the test controller, this needs to be viewed as UTF-8:

This is an em dash, —, this is is a delta symbol, ∆, this is an uppercase pi, ∏, and this is a lowercase pi, π.

Characters from unicode plane 1, like mathematical bold script capital a, 𝓐, and mathematical bold fraktur small u, 𝖚, work too.