Panic on rendering boolean

[justinpombrio]

This program:

extern crate mustache;

use std::io;
use mustache::MapBuilder;

fn main() {
    let template = mustache::compile_str("{{ok}}").unwrap();
    let data = MapBuilder::new()
        .insert_bool("ok", true)
        .build();
    template.render_data(&mut io::stdout(), &data).unwrap();
    println!();
}

fails with the following error:

thread 'main' panicked at 'bug: render_utag: unexpected value Bool(true).
Please report this issue on GitHub if you find an input that triggers this case.',
/home/justin/.cargo/registry/src/github.com-1ecc6299db9ec823/mustache-0.9.0/src/template.rs:224:25

Instead, I expect it to produce:

true

My thoughts:

• It would be nice to be able to use booleans in a template like {{ok}} and get 'true' or 'false'.
• Even if booleans can only be used as {{#ok}}...{{/ok}}, this is a poor error message.
• This error occurs in render_utag, but why should this be unescaped?

[Ryman]

Hi @justinpombrio, Thanks for the bug report!

You're right indeed this should be supported, I have submitted #61 which should hopefully fix your issue.

This error occurs in render_utag, but why should this be unescaped?

The rendering all happens through raw output and then converted to escaped variants after, see here if you are interested or want to improve it :)

[justinpombrio]

Thanks even more for the bug fix!