extern crate rcalc;

#[cfg(test)]
mod operators {
    use rcalc::Interpreter;

    #[test]
    fn it_does_addition() {
        assert_eq!(Interpreter::process("3+4").unwrap(), 7.);
    }

    #[test]
    fn it_does_subtraction() {
        assert_eq!(Interpreter::process("3-4").unwrap(), -1.);
    }

    #[test]
    fn it_does_multiplication() {
        assert_eq!(Interpreter::process("3*4").unwrap(), 12.);
    }

    mod division {
        use rcalc::Interpreter;

        #[test]
        fn it_does_division() {
            assert_eq!(Interpreter::process("3/4").unwrap(), 0.75);
        }

        #[test]
        fn it_does_integer_division() {
            assert_eq!(Interpreter::process("3./4").unwrap(), 0.);
        }

        #[test]
        fn it_does_modulo_division() {
            assert_eq!(Interpreter::process("10%3").unwrap(), 1.);
        }

    }

    mod factorial {
        use rcalc::Interpreter;

        #[test]
        fn it_does_factorial() {
            assert_eq!(Interpreter::process("5!").unwrap(), 120.);
        }

        #[test]
        fn it_does_factorial_with_even_negative() {
            use std::f64;
            assert_eq!(Interpreter::process("-2!").unwrap(), f64::INFINITY);
        }

        #[test]
        fn it_does_factorial_with_odd_negative() {
            use std::f64;
            assert_eq!(Interpreter::process("-3!").unwrap(), -f64::INFINITY);
        }
    }

    #[test]
    fn it_handles_unary_operators() {
        assert_eq!(Interpreter::process("-5 - + - 7").unwrap(), 2.);
    }
}