simd_json/value/tape/
array.rs

1use super::Value;
2use crate::Node;
3
4#[derive(Clone, Copy)]
5/// Wrapper around the tape that allows interacting with it via a `Array`-like API.
6pub struct Array<'tape, 'input>(pub(super) &'tape [Node<'input>]);
7
8pub struct Iter<'tape, 'input>(&'tape [Node<'input>]);
9
10impl<'tape, 'input> Iterator for Iter<'tape, 'input> {
11    type Item = Value<'tape, 'input>;
12
13    fn next(&mut self) -> Option<Self::Item> {
14        let (head, tail) = self.0.split_at(self.0.first()?.count());
15        self.0 = tail;
16        Some(Value(head))
17    }
18}
19
20// value_trait::Array for
21impl<'tape, 'input> Array<'tape, 'input>
22where
23    'input: 'tape,
24{
25    /// Gets a ref to a value based on n index, returns `None` if the
26    /// current Value isn't an Array or doesn't contain the index
27    /// it was asked for.
28    #[must_use]
29    pub fn get(&self, mut idx: usize) -> Option<Value<'tape, 'input>> {
30        let mut offset = 1;
31        while idx > 0 {
32            offset += self.0.get(offset)?.count();
33            idx -= 1;
34        }
35        let count = self.0.get(offset)?.count();
36        Some(Value(&self.0[offset..offset + count]))
37    }
38
39    /// Iterates over the values paris
40    #[must_use]
41    pub fn iter<'i>(&'i self) -> Iter<'tape, 'input> {
42        Iter(&self.0[1..])
43    }
44
45    /// Number of key/value pairs
46    /// # Panics
47    /// if the tape is not an array
48    #[must_use]
49    pub fn len(&self) -> usize {
50        if let Some(Node::Array { len, .. }) = self.0.first() {
51            *len
52        } else {
53            panic!("invalid tape array")
54        }
55    }
56    /// Returns if the array is empty
57    #[must_use]
58    pub fn is_empty(&self) -> bool {
59        self.len() == 0
60    }
61}
62
63impl<'tape, 'input> IntoIterator for &Array<'tape, 'input> {
64    type IntoIter = Iter<'tape, 'input>;
65    type Item = Value<'tape, 'input>;
66    fn into_iter(self) -> Self::IntoIter {
67        self.iter()
68    }
69}
70
71#[cfg(test)]
72mod test {
73    use crate::to_tape;
74    use value_trait::base::ValueAsScalar;
75
76    #[test]
77    fn get_ints() -> crate::Result<()> {
78        let mut input = b"[1,2,3,4]".to_vec();
79        let t = to_tape(input.as_mut_slice())?;
80        let v = t.as_value();
81        let a = v.as_array().expect("is an array");
82        assert_eq!(a.get(0).and_then(|v| v.as_u64()), Some(1));
83        assert_eq!(a.get(1).and_then(|v| v.as_u64()), Some(2));
84        assert_eq!(a.get(2).and_then(|v| v.as_u64()), Some(3));
85        assert_eq!(a.get(3).and_then(|v| v.as_u64()), Some(4));
86        assert_eq!(a.get(4), None);
87        Ok(())
88    }
89
90    #[test]
91    fn get_nested() -> crate::Result<()> {
92        let mut input = b"[1,[2,3],4]".to_vec();
93        let t = to_tape(input.as_mut_slice())?;
94        let v = t.as_value();
95        let a = v.as_array().expect("is an array");
96        assert_eq!(a.get(0).and_then(|v| v.as_u64()), Some(1));
97        let a1 = a.get(1).expect("has first element");
98        let a2 = a1.as_array().expect("is an array");
99        assert_eq!(a2.get(0).and_then(|v| v.as_u64()), Some(2));
100        assert_eq!(a2.get(1).and_then(|v| v.as_u64()), Some(3));
101        assert_eq!(a.get(2).and_then(|v| v.as_u64()), Some(4));
102        assert_eq!(a.get(3), None);
103        Ok(())
104    }
105
106    #[test]
107    fn iter() -> crate::Result<()> {
108        let mut input = b"[1,2,3,4]".to_vec();
109        let t = to_tape(input.as_mut_slice())?;
110        let v = t.as_value();
111        let a = v.as_array().expect("is an array");
112        let v = a
113            .iter()
114            .map(|v| v.as_u8().expect("integer"))
115            .collect::<Vec<_>>();
116
117        assert_eq!(v, vec![1, 2, 3, 4]);
118
119        Ok(())
120    }
121    #[test]
122    fn iter_container() -> crate::Result<()> {
123        let mut input = b"[1,[2,3],4]".to_vec();
124        let t = to_tape(input.as_mut_slice())?;
125        let v = t.as_value();
126        let a = v.as_array().expect("is an array");
127        let v = a.iter().map(|v| v.as_u8()).collect::<Vec<_>>();
128
129        assert_eq!(v, vec![Some(1), None, Some(4)]);
130
131        Ok(())
132    }
133}
simd_json/value/tape/array.rs

simd_json/value/tape/
array.rs
