Sqlx: Unable to use query_as with Postgres enum support

[ecton]

This example should be able to be run to create the test table, and then the unit tests will fail compilation because of the error:

the trait bound std::result::Result<std::option::Option<i32>, sqlx_core::error::Error>: sqlx::result_ext::ResultExt<std::option::Option<tests::ReprI32>> is not satisfied
the following implementations were found:
as sqlx::result_ext::ResultExt>
as sqlx::result_ext::ResultExt>>
, sqlx_core::error::Error> as sqlx::result_ext::ResultExt>

I've also tried this with the repr(32) and the text rename functionality. I tried looking for examples in the repository, but there are no hand-written examples, just ones that use some higher-level testing functionality.

I looked for missing trait includes, but couldn't find what should be included if anything. Any help is greatly appreciated!

The cargo dependencies section for the example:

[dependencies]
sqlx = {version = "0.3", default-features=false, features=[ "runtime-tokio", "macros" , "postgres", "uuid", "chrono",  "tls" ]}
tokio = {version = "*", features = ["macros"]}
anyhow = "*"
dotenv = "*"

The main.rs file:

use sqlx::postgres::PgPool;

async fn pg() -> PgPool {
    PgPool::new("postgres://testuser:password@localhost/testdb")
        .await
        .unwrap()
}

#[tokio::main]
async fn main() -> Result<(), anyhow::Error> {
    sqlx::query("CREATE TABLE testtable(intnullcolumn INT, intnotnullcolumn INT NOT NULL, textnullcolumn TEXT, textnotnullcolumn TEXT NOT NULL)").execute(&pg().await).await?;
    Ok(())
}

#[cfg(test)]
mod tests {
    use super::pg;
    #[derive(PartialEq, Copy, Clone, Debug, sqlx::Type)]
    #[repr(i32)]
    enum ReprI32 {
        Test = 0,
    }

    struct ReprI32OptionRow {
        value: Option<ReprI32>,
    }

    struct ReprI32Row {
        value: ReprI32,
    }

    #[tokio::test]
    async fn null_int_cast() -> Result<(), sqlx::Error> {
        sqlx::query_as!(
            ReprI32OptionRow,
            "SELECT intnullcolumn as value FROM testtable"
        )
        .fetch_one(&pg().await)
        .await
        .map(|_| ())
    }

    #[tokio::test]
    async fn not_null_int_cast() -> Result<(), sqlx::Error> {
        sqlx::query_as!(
            ReprI32Row,
            "SELECT intnotnullcolumn as value FROM testtable"
        )
        .fetch_one(&pg().await)
        .await
        .map(|_| ())
    }

    #[tokio::test]
    async fn not_null_into_option_cast() -> Result<(), sqlx::Error> {
        sqlx::query_as!(
            ReprI32OptionRow,
            "SELECT intnotnullcolumn as value FROM testtable"
        )
        .fetch_one(&pg().await)
        .await
        .map(|_| ())
    }
}

[abonander]

The macros are currently completely unaware of custom types, but we can roll this in with the following proposal: https://github.com/launchbadge/sqlx/issues/121#issuecomment-609231325

I'm starting on that right after #249 is merged as it lays some groundwork for it.

[ecton]

Awesome, thank you for the info. If you'd prefer to close this rather than keeping it open, feel free, I can follow along on the other issues.

[phated]

I just ran into this also. Excited to see how decoupled mode helps to support this!

[abonander]

It doesn't directly, but the refactors I did in the course of implementing that lead directly into supporting this and #121 .

[mehcode]

Initial support for user-defined types in macros is being tracked in #397