summaryrefslogtreecommitdiffstats
path: root/vendor/toml-0.5.11/src/spanned.rs
blob: f90c5492d9df8599758658603544e3596bf21af9 (plain)
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
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
use serde::{de, ser};
use std::borrow::Borrow;
use std::cmp::Ordering;
use std::fmt;
use std::hash::{Hash, Hasher};

pub(crate) const NAME: &str = "$__toml_private_Spanned";
pub(crate) const START: &str = "$__toml_private_start";
pub(crate) const END: &str = "$__toml_private_end";
pub(crate) const VALUE: &str = "$__toml_private_value";

/// A spanned value, indicating the range at which it is defined in the source.
///
/// ```
/// use serde_derive::Deserialize;
/// use toml::Spanned;
///
/// #[derive(Deserialize)]
/// struct Value {
///     s: Spanned<String>,
/// }
///
/// let t = "s = \"value\"\n";
///
/// let u: Value = toml::from_str(t).unwrap();
///
/// assert_eq!(u.s.start(), 4);
/// assert_eq!(u.s.end(), 11);
/// assert_eq!(u.s.get_ref(), "value");
/// assert_eq!(u.s.into_inner(), String::from("value"));
/// ```
#[derive(Clone, Debug)]
pub struct Spanned<T> {
    /// The start range.
    start: usize,
    /// The end range (exclusive).
    end: usize,
    /// The spanned value.
    value: T,
}

impl<T> Spanned<T> {
    /// Access the start of the span of the contained value.
    pub fn start(&self) -> usize {
        self.start
    }

    /// Access the end of the span of the contained value.
    pub fn end(&self) -> usize {
        self.end
    }

    /// Get the span of the contained value.
    pub fn span(&self) -> (usize, usize) {
        (self.start, self.end)
    }

    /// Consumes the spanned value and returns the contained value.
    pub fn into_inner(self) -> T {
        self.value
    }

    /// Returns a reference to the contained value.
    pub fn get_ref(&self) -> &T {
        &self.value
    }

    /// Returns a mutable reference to the contained value.
    pub fn get_mut(&mut self) -> &mut T {
        &mut self.value
    }
}

impl Borrow<str> for Spanned<String> {
    fn borrow(&self) -> &str {
        self.get_ref()
    }
}

impl<T: PartialEq> PartialEq for Spanned<T> {
    fn eq(&self, other: &Self) -> bool {
        self.value.eq(&other.value)
    }
}

impl<T: Eq> Eq for Spanned<T> {}

impl<T: Hash> Hash for Spanned<T> {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.value.hash(state);
    }
}

impl<T: PartialOrd> PartialOrd for Spanned<T> {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        self.value.partial_cmp(&other.value)
    }
}

impl<T: Ord> Ord for Spanned<T> {
    fn cmp(&self, other: &Self) -> Ordering {
        self.value.cmp(&other.value)
    }
}

impl<'de, T> de::Deserialize<'de> for Spanned<T>
where
    T: de::Deserialize<'de>,
{
    fn deserialize<D>(deserializer: D) -> Result<Spanned<T>, D::Error>
    where
        D: de::Deserializer<'de>,
    {
        struct SpannedVisitor<T>(::std::marker::PhantomData<T>);

        impl<'de, T> de::Visitor<'de> for SpannedVisitor<T>
        where
            T: de::Deserialize<'de>,
        {
            type Value = Spanned<T>;

            fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
                formatter.write_str("a TOML spanned")
            }

            fn visit_map<V>(self, mut visitor: V) -> Result<Spanned<T>, V::Error>
            where
                V: de::MapAccess<'de>,
            {
                if visitor.next_key()? != Some(START) {
                    return Err(de::Error::custom("spanned start key not found"));
                }

                let start: usize = visitor.next_value()?;

                if visitor.next_key()? != Some(END) {
                    return Err(de::Error::custom("spanned end key not found"));
                }

                let end: usize = visitor.next_value()?;

                if visitor.next_key()? != Some(VALUE) {
                    return Err(de::Error::custom("spanned value key not found"));
                }

                let value: T = visitor.next_value()?;

                Ok(Spanned { start, end, value })
            }
        }

        let visitor = SpannedVisitor(::std::marker::PhantomData);

        static FIELDS: [&str; 3] = [START, END, VALUE];
        deserializer.deserialize_struct(NAME, &FIELDS, visitor)
    }
}

impl<T: ser::Serialize> ser::Serialize for Spanned<T> {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: ser::Serializer,
    {
        self.value.serialize(serializer)
    }
}