Function mz_transform::fusion::join::unpack_equivalences

fn unpack_equivalences(
    equivalences: &Vec<Vec<MirScalarExpr>>,
) -> Vec<MirScalarExpr>

Unpacks multiple equivalence classes into conjuncts that should all be true, essentially turning join equivalences into a Filter.

Note that a join equivalence treats null equal to null, while an = in a Filter does not. This function is mindful of this.