`PartialOrd` bound requires `T: Ord, Self: Eq`, not `T: PartialOrd, Self: PartialEq`

[stevenengler]

If I derive both PartialOrd and Ord, I get unexpected bounds for PartialOrd.

#[derive(educe::Educe)]
#[educe(PartialEq, Eq, PartialOrd)]
pub struct Foo<T>(T);

results in:

impl<T> ::core::cmp::PartialOrd for Foo<T>
where
    T: ::core::cmp::PartialOrd,
    Self: ::core::cmp::PartialEq,
{ ... }

but:

#[derive(educe::Educe)]
#[educe(PartialEq, Eq, PartialOrd, Ord)]
pub struct Foo<T>(T);

results in:

impl<T> ::core::cmp::PartialOrd for Foo<T>
where
    T: ::core::cmp::Ord,
    Self: ::core::cmp::Eq,
{ ... }

If we compare this to the standard library, we get the expected bounds:

#[derive(PartialEq, Eq, PartialOrd, Ord)]
pub struct Foo<T>(T);

impl<T: ::core::cmp::PartialOrd> ::core::cmp::PartialOrd for Foo<T> { ... }

(And why does educe add a Self bound here?)