[codegen] Struct / enum derive `PartialEq` should also derive `Eq`

[billy1624]

Motivation

New clippy lint was added in Rust 1.63.0. which checks for types that derive PartialEq and could implement Eq.

Example:

#[derive(PartialEq)]
struct Foo {
    i_am_eq: i32,
    i_am_eq_too: Vec<String>,
}

Do this instead:

#[derive(PartialEq, Eq)]
struct Foo {
    i_am_eq: i32,
    i_am_eq_too: Vec<String>,
}

Proposed Solutions

Check sea-orm-codegen where #[derive(PartialEq)] should be changed to #[derive(PartialEq, Eq)].

Additional Information

Clippy lints index: https://rust-lang.github.io/rust-clippy/master/index.html#derive_partial_eq_without_eq

[billy1624]

Thanks! @baoyachi

[baoyachi]

Oh，I see you've done it。

[billy1624]

Nope, it's not

[billy1624]

https://github.com/SeaQL/sea-orm/pull/967 doesn't touch code generator of codegen

[baoyachi]

It's seem's touch sea-query create

...
/// Value variants
///
/// We want Value to be exactly 1 pointer sized, so anything larger should be boxed.
+ #[derive(Clone, Debug, PartialEq)]
pub enum Value {
    Bool(Option<bool>),
    TinyInt(Option<i8>),
    SmallInt(Option<i16>),
    Int(Option<i32>),
...

[baoyachi]

So，first need change sea-query?

[tyt2y3]

I don't think we need an option for this behaviour. It seems to be universally true that we want Eq and PartialEq wherever possible.

We can simply change the codegen for enum. For any struct (that contains a f64), implementing Eq is not possible.

[billy1624]

There are only three place in the codegen we need to modify:

• https://github.com/SeaQL/sea-orm/blob/d262501a44c048ed36a17bbf661ced3c5193f455/sea-orm-codegen/src/entity/active_enum.rs#L33-L42
• https://github.com/SeaQL/sea-orm/blob/d262501a44c048ed36a17bbf661ced3c5193f455/sea-orm-codegen/src/entity/writer.rs#L387-L390
• https://github.com/SeaQL/sea-orm/blob/d262501a44c048ed36a17bbf661ced3c5193f455/sea-orm-codegen/src/entity/writer.rs#L623-L633

Btw... both f32 and f64 does not implement Eq but implemented PartialEq

[w93163red]

May I take this one? If I understand correctly, only the above files need to be changed?

[billy1624]

Hey @w93163red, sure! Please go ahead :)

[billy1624]

But note that if we have any f32 / f64 fields in the model, it shouldn't derive Eq (PartialEq is allowed). Also, we need to add a test cases for this as well.

[w93163red]

I submitted a PR. If you find anything wrong, please let me know. Thanks~

[billy1624]

Thanks! @w93163red Please check the comment: https://github.com/SeaQL/sea-orm/pull/988#pullrequestreview-1084965612