lbnf 0.1.0

A crate for parsing LBNF grammar
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

use crate::grammar::{Cat, Def, Exp, Grammar, Ident, Item, Label};
use proptest::prelude::{
    any, any_with, prop_assert_eq, prop_oneof, proptest, Arbitrary, BoxedStrategy, Just, Strategy,
};

impl Arbitrary for Grammar {
    type Parameters = ();

    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        any::<Vec<Def>>()
            .prop_map(|definitions| Grammar { definitions })
            .boxed()
    }
}

impl Arbitrary for Def {
    type Parameters = ();

    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        prop_oneof![
            (any::<Label>(), any::<Cat>(), any::<Vec<Item>>())
                .prop_map(|(a, b, c)| Self::Rule(a, b, c)),
            (any::<Ident>(), any::<Vec<Exp>>()).prop_map(|(a, b)| Self::Macro(a, b)),
        ]
        .boxed()
    }
}

impl Arbitrary for Item {
    type Parameters = ();

    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        prop_oneof![
            any_with::<String>(r#"[.--"]*"#.into()).prop_map(Item::Terminal),
            any::<Cat>().prop_map(Item::NTerminal),
        ]
        .boxed()
    }
}

impl Arbitrary for Cat {
    type Parameters = ();

    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        let leaf = prop_oneof![
            any::<Ident>().prop_map(Cat::IdCat),
            any::<Ident>().prop_map(|a| Cat::ListCat(Box::new(Cat::IdCat(a)))),
            any::<Ident>()
                .prop_map(|a| Cat::ListCat(Box::new(Cat::ListCat(Box::new(Cat::IdCat(a)))))),
        ];
        leaf.prop_recursive(8, 8, 1, |inner| {
            prop_oneof![inner
                .clone()
                .prop_map(|inner| Cat::ListCat(Box::new(inner)))]
        })
        .boxed()
    }
}

impl Arbitrary for Exp {
    type Parameters = ();

    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        prop_oneof![
            any::<Ident>().prop_map(Self::Var),
            any::<i64>().prop_map(Self::LitInt),
            any::<f64>().prop_map(Self::LitDouble),
            any_with::<String>(r#"[.--"]"#.into())
                .prop_map(|s| Self::LitChar(s.chars().next().unwrap())),
            any_with::<String>(r#"[.--"]*"#.into()).prop_map(Self::LitString),
        ]
        .boxed()
    }
}

impl Arbitrary for Label {
    type Parameters = ();

    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        prop_oneof![
            Just(Self::Wild),
            Just(Self::ListE),
            Just(Self::ListCons),
            Just(Self::ListOne),
            any::<Ident>().prop_map(Self::Id),
        ]
        .boxed()
    }
}

impl Arbitrary for Ident {
    type Parameters = ();
    type Strategy = BoxedStrategy<Self>;

    fn arbitrary_with((): Self::Parameters) -> Self::Strategy {
        prop_oneof![any_with::<String>("[a-zA-Z][a-zA-Z0-9_]*".into()).prop_map(Self)].boxed()
    }
}

proptest! {
    #[test]
    fn test_parse_grammar(source : Grammar) {
        let regular = format!("{}", source);
        let parsed_node = crate::parse(&regular);
        prop_assert_eq!(
            Ok(&source),
            parsed_node.as_ref(),
            "\n---- Formatted grammar ----\n{}",
            regular
        );

        let pretty = format!("{:#}", source);
        let parsed_node = crate::parse(&pretty);
        prop_assert_eq!(
            Ok(&source),
            parsed_node.as_ref(),
            "\n---- Formatted grammar (with # flag) ----\n{}",
            pretty
        );

    }
}