`fmpz_poly_is_squarefree` wrong results?

[fingolfin]

It indicates that 4x is square-free, but that doesn't agree with its documentation, which states

Returns whether the polynomial poly is square-free. A non-zero polynomial is defined to be square-free if it has no non-unit square factors. We also define the zero polynomial to be square-free.

See also https://github.com/Nemocas/Nemo.jl/pull/1742 and https://github.com/Nemocas/Nemo.jl/issues/1311

[albinahlback]

A change to something like

Returns whether the polynomial poly is square-free. A non-zero polynomial is defined to be square-free if its factorisation contains no non-constant square factors. We also define the zero polynomial to be square-free.

would work, right?

[fingolfin]

Thank you. That would at least clarify that it deviates from the usual mathematical definition. Perhaps it could be made even more explicitly by in addition inserting something like this:

This differs somewhat from the usual definition, e.g. we consider the polynomial 4x in Z[x] as square-free.

[thofma]

Or just write, that it returns whether poly is squarefree as a polynomial over the rationals.

[edgarcosta]

That or just say it doesn't double roots over the complex numbers