Halo headlights and turn signal question

I don't think you can do this with just diodes, as the parking light circuit is just "one" not left/ right
What if he simply runs one wire (with diode) from the left parking light to the left halo
Then run one wire (also with diode) from the left turn signal to the same input wire on the halo
Do the same for the right and done

I could be wrong of course, but why wouldn't this work?