rhai/tests/print.rs

use rhai::{Engine, EvalAltResult, RegisterFn, INT};
use std::sync::{Arc, RwLock};

#[test]
fn test_print_debug() -> Result<(), Box<EvalAltResult>> {
    let logbook = Arc::new(RwLock::new(Vec::<String>::new()));

    // Redirect print/debug output to 'log'
    let log1 = logbook.clone();
    let log2 = logbook.clone();

    let mut engine = Engine::new();

    engine
        .on_print(move |s| log1.write().unwrap().push(format!("entry: {}", s)))
        .on_debug(move |s, pos| {
            log2.write()
                .unwrap()
                .push(format!("DEBUG at {:?}: {}", pos, s))
        });

    // Evaluate script
    engine.eval::<()>("print(40 + 2)")?;
    engine.eval::<()>(r#"let x = "hello!"; debug(x)"#)?;

    // 'logbook' captures all the 'print' and 'debug' output
    assert_eq!(logbook.read().unwrap().len(), 2);
    assert_eq!(logbook.read().unwrap()[0], "entry: 42");
    assert_eq!(logbook.read().unwrap()[1], r#"DEBUG at 1:19: "hello!""#);

    for entry in logbook.read().unwrap().iter() {
        println!("{}", entry);
    }

    Ok(())
}

#[derive(Debug, Clone, Eq, PartialEq, Hash, Default)]
struct MyStruct {
    field: INT,
}

impl std::fmt::Display for MyStruct {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "hello: {}", self.field)
    }
}

#[cfg(not(feature = "no_object"))]
#[test]
fn test_print_custom_type() -> Result<(), Box<EvalAltResult>> {
    let mut engine = Engine::new();

    engine
        .register_type_with_name::<MyStruct>("MyStruct")
        .register_fn("to_debug", |x: &mut MyStruct| x.to_string())
        .register_fn("debug", |x: &mut MyStruct| x.to_string())
        .register_fn("new_ts", || MyStruct { field: 42 });

    engine.consume("let x = new_ts(); debug(x);")?;

    #[cfg(not(feature = "no_index"))]
    assert_eq!(
        engine.eval::<String>(
            r#"
                let x = [ 123, true, (), "world", new_ts() ];
                x.to_string()
            "#
        )?,
        r#"[123, true, (), "world", hello: 42]"#
    );

    assert!(engine
        .eval::<String>(
            r#"
                let x = #{ a:123, b:true, c:(), d:"world", e:new_ts() };
                x.to_string()
            "#
        )?
        .contains(r#""e": hello: 42"#));
    Ok(())
}