Running waveshaper-simple.html in ToT produces:

PASS > [simple] 
PASS   WaveShaper.curve is equal to ${expected}.
PASS   WaveShaper.oversample is equal to none.
PASS   Waveshaper.oversample = "2x" is equal to 2x.
PASS   Waveshaper.oversample = "4x" is equal to 4x.
PASS   Waveshaper.oversample = "invalid" is equal to 4x.
PASS   WaveShaper.curve is identical to the array [-1,0.25,0.75].
PASS   Waveshaper.curve = null is equal to ${expected}.
PASS < [simple] All assertions passed. (total 7 assertions)

That "${expected}" is not expected.  Need to fix this.