IntoActiveValue is not implemented for Vec<String>

[AdamJSoftware]

Description

I am trying to implement DeriveIntoActiveModel for the following struct

#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, JsonSchema, DeriveIntoActiveModel)]
pub struct BusinessCreate {
    pub location: Option<String>,
    pub how_we_sell_products: Option<String>,
    ...
    pub tags: Vec<String>,
}

I have a field called tags that just contains a field of strings. When using the macro, I get the following error:

the trait `IntoActiveValue<_>` is not implemented for `std::vec::Vec<std::string::String>`

Is there a way around this?

[avtrujillo]

Looks like implementations are defined starting here for the following:

• Option<V>> where V: IntoActiveValue<V> + Into<Value> + Nullable,
• Option<Option<V>> where V: IntoActiveValue<V> + Into<Value> + Nullable,
• bool
• i8
• i16
• i32
• i64
• u8
• u16
• u32
• u64
• f32
• f64
• &'static str
• String
• Vec<u8>

The first two are implemented manually, with the rest being implemented using the impl_into_active_value macro. The explanation for the implementation being only for Vec<u8> and not other Vec types is presumably that ActiveValue::Set(V) has the trait bound V: Into, and Into is implemented for Vec<u8> because Vec<u8> is converted into Value::Bytes. It's also implemented here for Vec<V>, but inside a module that requires the "postgres-array" feature to be enabled. Any fix for this would therefore need to be gated behind the "postgres-array" feature in order to work properly.

Edit: I tried doing this

#[cfg(feature = "postgres-array")]
impl IntoActiveValue<Vec> for Vec
where
V: IntoActiveValue + Into + Nullable + sea_query::ValueType + sea_query::with_array::NotU8

but got an error helpfully informing me that

upstream crates may add a new impl of trait sea_query::with_array::NotU8 for type u8 in future versions

Removing the sea_query::with_array::NotU8 bound produces conflicting implementations. Removing the NotU8 bound and deleting impl_into_active_value!(Vec<u8>) just gives me an error informing me that

the trait bound V: NotU8 is not satisfied
required for sea_query::Value to implement From<Vec<V>>
required for Vec<V> to implement `Into<sea_query::Value>

So it looks like we might be blocked on the stabilization of negative trait bounds.