Those (and similar symbols) have actually been used in several Node testing frameworks. See e.g. nodeunit (https://github.com/masylum/testosterone), Vows (http://vowsjs.org/), and Testosterone (https://github.com/masylum/testosterone).

I wanted to use "CIRCLE WITH LEFT HALF BLACK" for pending tests (see: http://en.wikipedia.org/wiki/Geometric_Shapes) .. alas, not supported in my terminal .. maybe I was doing it wrong.