I assumed that "tests" refers to a program too, which in this example is likely GPL. Thus GPL would stick already on the AI-rewrite of GPL test code.

If "tests" should mean a proper specification let's say some IETF RFC of a protocol, then that would be different.

Yes, I had not specified in my original comment. But in the SOTA LLM world code/text boundary is so blurry, so as to be non-existent.