bool-logic 0.3.3

A library for manipulating and evaluating boolean expressions
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140

use crate::ast::Expr;
use crate::visit_mut::VisitMut;
use crate::visit_mut::walk_mut_expr;

pub struct DedupList;

impl<T> VisitMut<T> for DedupList
where
    T: Eq,
{
    fn visit_mut_expr(&mut self, expr: &mut Expr<T>) {
        walk_mut_expr(self, expr);

        if let Some(list) = expr.as_mut_expr_list() {
            let mut i = 0;
            while i < list.len() {
                let mut j = i + 1;
                while j < list.len() {
                    if list[i] == list[j] {
                        list.remove(j);
                    } else {
                        j += 1;
                    }
                }
                i += 1;
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::ast::{all, any, const_, expr, not, var};

    #[test]
    fn dedup_any_with_duplicates() {
        let mut x: Expr<u32> = expr(any((var(1), var(2), var(1), var(3), var(2))));
        let expected: Expr<u32> = expr(any((var(1), var(2), var(3))));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_all_with_duplicates() {
        let mut x: Expr<u32> = expr(all((var(1), var(2), var(1), var(3), var(2))));
        let expected: Expr<u32> = expr(all((var(1), var(2), var(3))));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_no_duplicates() {
        let mut x: Expr<u32> = expr(any((var(1), var(2), var(3))));
        let expected: Expr<u32> = expr(any((var(1), var(2), var(3))));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_empty_list() {
        let mut x: Expr<u32> = expr(any(()));
        let expected: Expr<u32> = expr(any(()));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_single_element() {
        let mut x: Expr<u32> = expr(any((var(1),)));
        let expected: Expr<u32> = expr(any((var(1),)));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_all_same_elements() {
        let mut x: Expr<u32> = expr(any((var(1), var(1), var(1), var(1))));
        let expected: Expr<u32> = expr(any((var(1),)));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_nested_expressions() {
        let mut x: Expr<u32> = expr(any((
            all((var(1), var(2))),
            var(3),
            all((var(1), var(2))),
            var(3),
        )));
        let expected: Expr<u32> = expr(any((all((var(1), var(2))), var(3))));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_with_constants() {
        let mut x: Expr<u32> = expr(any((const_(true), var(1), const_(true), const_(false))));
        let expected: Expr<u32> = expr(any((const_(true), var(1), const_(false))));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_preserves_order() {
        let mut x: Expr<u32> = expr(any((var(3), var(1), var(2), var(1), var(3))));
        let expected: Expr<u32> = expr(any((var(3), var(1), var(2))));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }

    #[test]
    fn dedup_non_list_expression() {
        let mut x: Expr<u32> = expr(not(var(1)));
        let expected: Expr<u32> = expr(not(var(1)));

        DedupList.visit_mut_expr(&mut x);

        assert_eq!(x.to_string(), expected.to_string());
    }
}