We propose an experiment to test for broken time-reversal symmetry in the high-temperature superconductors. We configure a superconducting quantum interference device (SQUID) in a manner similar to that used recently to test for d(x2-y2) symmetry, but where one junction is on a crystal face of arbitrary angle. Assuming a d(x2-y2) + iepsilond(xy) symmetry, we calculate the magnetic diffraction patterns for the SQUID for various values of epsilon and angle. For any nonzero epsilon, i.e., time-reversal symmetry breaking, we find a nonzero circulating current spontaneously arises in the SQUID even in zero applied magnetic field and zero bias current.