rhai/tests/decrement.rs

use rhai::{Engine, EvalAltResult, INT};

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

    assert_eq!(engine.eval::<INT>("let x = 10; x -= 7; x")?, 3);

    assert!(matches!(engine
            .eval::<String>(r#"let s = "test"; s -= "ing"; s"#)
            .expect_err("expects error"), EvalAltResult::ErrorFunctionNotFound(err, _) if err == "- (string, string)"));

    Ok(())
}