#[cfg(test)]
mod tests {
    use crate::ast::{add_binary_node, Node, Token};

    #[test]
    fn add_nodes() {
        let mut stack = vec![Node::Leaf(true), Node::Leaf(false)];
        let rhs = vec![Node::Binary {
            operator: Token::Conjunction,
            lhs: Box::new(Node::Leaf(true)),
            rhs: Box::new(Node::Leaf(false)),
        }];
        add_binary_node(&mut stack, Token::Conjunction);
        assert_eq!(stack, rhs);
    }

    #[test]
    fn ast_to_formula_bool() {
        let formula = "01&";
        assert_eq!(
            Node::<bool>::ast_to_formula(&Node::<bool>::parse_formula(formula)),
            formula
        );
        let formula = "01&00|&";
        assert_eq!(
            Node::<bool>::ast_to_formula(&Node::<bool>::parse_formula(formula)),
            formula
        );
        let formula = "01&00|&11^&";
        assert_eq!(
            Node::<bool>::ast_to_formula(&Node::<bool>::parse_formula(formula)),
            formula
        );
        let formula = "01&00|&11=^";
        assert_eq!(
            Node::<bool>::ast_to_formula(&Node::<bool>::parse_formula(formula)),
            formula
        );
        let formula = "01&00|&0!=";
        assert_eq!(
            Node::<bool>::ast_to_formula(&Node::<bool>::parse_formula(formula)),
            formula
        );
    }

    #[test]
    fn ast_to_formula_char() {
        let formula = "AB&";
        assert_eq!(
            Node::<char>::ast_to_formula(&Node::<char>::parse_formula(formula)),
            formula
        );
        let formula = "AB&CD|&";
        assert_eq!(
            Node::<char>::ast_to_formula(&Node::<char>::parse_formula(formula)),
            formula
        );
        let formula = "AB&AC|&DE^&";
        assert_eq!(
            Node::<char>::ast_to_formula(&Node::<char>::parse_formula(formula)),
            formula
        );
        let formula = "AB&CD|&EF=^";
        assert_eq!(
            Node::<char>::ast_to_formula(&Node::<char>::parse_formula(formula)),
            formula
        );
        let formula = "AB&CD|&E!=";
        assert_eq!(
            Node::<char>::ast_to_formula(&Node::<char>::parse_formula(formula)),
            formula
        );
    }
}