How to use newtypes?

[teenjuna]

Hi! I'm trying to use this library with struct wrappers (also known as newtypes), but have no luck.

For example, consider this code:

#[derive(Debug, sqlx::Type)]
#[repr(transparent)]
pub struct Text(String);

#[derive(Debug, FromRow)]
pub struct Article {
    pub id: i16,
    pub text: Text,
}

Which connects to a postgres database with this scheme:

CREATE TABLE articles (
    id   smallserial PRIMARY KEY,
    text text        NOT NULL
);

When I try to query an article like this:

let article = sqlx::query_as!(Article, "SELECT * FROM articles WHERE id = $1", id).fetch_one(pool).await?;

I get this compile error:

expected struct `Text`, found struct `String`

What am I doing wrong? Basically I want the returned String to be just wrapped with my Text type.

[teenjuna]

Okay, seems like I should do this:

let article = sqlx::query_as!(Article, "SELECT id, text as "text: _" FROM articles WHERE id = $1", id).fetch_one(pool).await?;

Which is really verbose in my actual use case, so I wonder if something like this is considered.

However, now I don't understand how to INSERT such struct!

let article = sqlx::query_as!(Article, "INSERT into articles (text) VALUES ($1)", text).fetch_one(pool).await?;

Results in errors like this:

expected `&str`, found struct `Text`

Although this particular case could be fixed by replacing text with &text.0, if there's more generic way? For example, I could have a wrapper around Vec<Text>, is there something better than texts.into_iter().map(|t| &t.0).collect::<Vec<&str>>?

[teenjuna]

I've asked the same question on the rust forum (link). I think I did a better job describing my problem there. I also think it's the same problem as #1672.