Fix merging types in multiple #[into] attributes

[tyranron]

Synopsis

Types are not always merged correctly when multiple #[into] attributes are specified.

#[derive(Clone, Copy, Debug, Into)]
#[into(ref)]
#[into(owned)]
#[into((Wrapped<i32>, Transmuted<f32>))]
#[into(ref_mut((Wrapped<i32>, Transmuted<f32>)))]
struct Tuple(
    Wrapped<i32>,
    Wrapped<f32>,
);

expands as

#[automatically_derived]
impl ::core::convert::From<Tuple> for (Wrapped<i32>, Transmuted<f32>) {
    #[inline]
    fn from(value: Tuple) -> Self { (<Wrapped<i32> as ::core::convert::From<_>>::from(value.0), <Transmuted<f32> as ::core::convert::From<_>>::from(value.1)) }
}
#[automatically_derived]
impl<'__derive_more_into> ::core::convert::From<&'__derive_more_into Tuple> for (&'__derive_more_into Wrapped<i32>,
                                                                                 &'__derive_more_into Wrapped<f32>) {
    #[inline]
    fn from(value: &'__derive_more_into Tuple) -> Self { (<&Wrapped<i32> as ::core::convert::From<_>>::from(&value.0), <&Wrapped<f32> as ::core::convert::From<_>>::from(&value.1)) }
}
#[automatically_derived]
impl<'__derive_more_into> ::core::convert::From<&'__derive_more_into mut Tuple> for (&'__derive_more_into mut Wrapped<i32>, &'__derive_more_into mut Transmuted<f32>) {
    #[inline]
    fn from(value: &'__derive_more_into mut Tuple) -> Self { (<&mut Wrapped<i32> as ::core::convert::From<_>>::from(&mut value.0), <&mut Transmuted<f32> as ::core::convert::From<_>>::from(&mut value.1)) }
}

So, the #[into((Wrapped<i32>, Transmuted<f32>))] is totally missed in the expanded macro.

Solution

Fix merging multiple #[into(<types>)] attributes so all the specified conversions are used

Checklist

• Documentation is updated (not required)
• Tests are added/updated (if required)
• CHANGELOG entry is added (not required)

[tyranron]

ping @JelteF