They MAY already have done so. Perhaps the powers that be simply aren't telling us, so "they", whoever "they" are, find it necessary to give us something that EVERYONE will see.
A simple child's kaleidoscope can reproduce these geometric shapes on a random basis.
Not really. Crop circle formations have depicted the inner solar system, a DNA strand, the Mandlebrot set, and many other patterns whose chance of being randomly generated are at least several billion to one.
Are "they" testing" us? If so, to what purpose?
To both questions.. I don't know.