rhai/tests/eval.rs

use rhai::{Engine, EvalAltResult, LexError, ParseErrorType, Scope, INT};

#[test]
fn test_eval() -> Result<(), Box<EvalAltResult>> {
    let engine = Engine::new();

    assert_eq!(engine.eval::<INT>(r#"eval("40 + 2")"#)?, 42);

    assert_eq!(
        engine.eval::<INT>(
            r#"
                let foo = 42;

                eval("let foo = 123");
                eval("let xyz = 10");

                foo + xyz
            "#
        )?,
        133
    );

    Ok(())
}

#[test]
fn test_eval_blocks() -> Result<(), Box<EvalAltResult>> {
    let engine = Engine::new();

    assert_eq!(
        engine.eval::<INT>(
            r#"
                let x = 999;

                eval("let x = x - 1000");

                let y = if x < 0 {
                    eval("let x = 42");
                    x
                } else {
                    0
                };

                x + y
            "#
        )?,
        41
    );

    assert_eq!(
        engine.eval::<INT>(
            r#"
                let foo = 42;

                eval("{ let foo = 123; }");

                foo
            "#
        )?,
        42
    );

    assert_eq!(
        engine.eval::<INT>(
            r#"
                let foo = 42;
                { { {
                    eval("let foo = 123");
                } } }
                foo
            "#
        )?,
        42
    );

    Ok(())
}

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

    assert_eq!(
        engine.eval::<INT>(
            r#"
                const XYZ = 123;

                fn foo() { global::XYZ } 
                {
                    eval("const XYZ = 42;");
                }

                foo()
            "#
        )?,
        123
    );

    assert_eq!(
        engine.eval::<INT>(
            r#"
                const XYZ = 123;

                fn foo() { global::XYZ } 

                eval("const XYZ = 42;");

                foo()
            "#
        )?,
        42
    );

    Ok(())
}

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

    assert_eq!(
        engine.eval_with_scope::<INT>(
            &mut scope,
            r#"
                let x = 10;

                fn foo(x) { x += 12; x }

                let script = "let y = x;";      // build a script
                script +=    "y += foo(y);";
                script +=    "x + y";

                eval(script) + x + y
            "#
        )?,
        84
    );

    assert_eq!(
        scope
            .get_value::<INT>("x")
            .expect("variable x should exist"),
        10
    );

    assert_eq!(
        scope
            .get_value::<INT>("y")
            .expect("variable y should exist"),
        32
    );

    assert!(scope.contains("script"));
    assert_eq!(scope.len(), 3);

    Ok(())
}

#[test]
fn test_eval_disabled() -> Result<(), Box<EvalAltResult>> {
    let mut engine = Engine::new();

    engine.disable_symbol("eval");

    assert!(matches!(
        engine
            .compile(r#"eval("40 + 2")"#)
            .unwrap_err()
            .err_type(),
        ParseErrorType::BadInput(LexError::ImproperSymbol(err, ..)) if err == "eval"
    ));

    Ok(())
}