Derive Clone for tera::Error

[jblachly]

This is also sort of a wishlist item for v2 (#637) but OTOH could be added to existing version without breaking API compat.

Use case: obtaining a pre-parsed Tera instance in multiple functions throughout a module.

pub static TEMPLATES_PATH: &'static str = "templates/register/**/*.html";

static TEMPLATES: LazyLock<Result<Tera, tera::Error>> = LazyLock::new(|| {
    Tera::new(TEMPLATES_PATH).map_err(|e| {
        tracing::error!("Template parsing error(s): {}", e);
        e
    })
});

pub fn tera_instance() -> Result<Tera, tera::Error> {
    let tera = if cfg!(debug_assertions) {
        // in dev only allow hot reloading
        Tera::new(TEMPLATES_PATH)
    } else {
        TEMPLATES.clone()
    };
    tera
}

[Keats]

The issue is always io::Error which cannot be cloned

[jblachly]

I may be misunderstanding -- the Tera ErrorKind enum wraps std::io::ErrorKind, which is cloneable.

[Keats]

Ah true for some reasons i thought it was io:Error. Tera2 already has Clone implemented: https://github.com/Keats/tera2/blob/master/tera/src/errors.rs#L35

[jblachly]

Didn't even know about Tera2, thanks!

[Keats]

It's a WIP working pretty well already and with some experiments like Keats/tera2#51