dashu_int/third_party/
serde.rs

1//! Implement serde traits.
2
3use crate::{convert::words_to_le_bytes, ibig::IBig, ubig::UBig};
4use core::fmt::{self, Formatter};
5use serde::{
6    de::{self, Deserialize, Deserializer, Visitor},
7    ser::{Serialize, Serializer},
8};
9
10impl Serialize for UBig {
11    #[inline]
12    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
13        if serializer.is_human_readable() {
14            serializer.collect_str(self)
15        } else if self.is_zero() {
16            serializer.serialize_bytes(&[])
17        } else {
18            let bytes = words_to_le_bytes::<false>(self.as_words());
19            serializer.serialize_bytes(&bytes)
20        }
21    }
22}
23
24impl<'de> Deserialize<'de> for UBig {
25    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
26        if deserializer.is_human_readable() {
27            deserializer.deserialize_str(UBigVisitor)
28        } else {
29            deserializer.deserialize_bytes(UBigVisitor)
30        }
31    }
32}
33
34/// UBig is serialized as little-endian bytes.
35struct UBigVisitor;
36
37impl<'de> Visitor<'de> for UBigVisitor {
38    type Value = UBig;
39
40    fn expecting(&self, f: &mut Formatter) -> fmt::Result {
41        write!(f, "a string or a sequence of bytes")
42    }
43
44    fn visit_str<E: de::Error>(self, v: &str) -> Result<Self::Value, E> {
45        match UBig::from_str_with_radix_prefix(v) {
46            Ok((n, _)) => Ok(n),
47            Err(e) => Err(de::Error::custom(e)),
48        }
49    }
50
51    fn visit_bytes<E: de::Error>(self, v: &[u8]) -> Result<Self::Value, E> {
52        Ok(UBig::from_le_bytes(v))
53    }
54}
55
56impl Serialize for IBig {
57    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
58        if serializer.is_human_readable() {
59            serializer.collect_str(self)
60        } else if self.is_zero() {
61            serializer.serialize_bytes(&[])
62        } else {
63            // Two's complement little-endian bytes (sign encoded in the high bits),
64            // matching `IBig::to_le_bytes()` for interop robustness.
65            let bytes = self.to_le_bytes();
66            serializer.serialize_bytes(&bytes)
67        }
68    }
69}
70
71impl<'de> Deserialize<'de> for IBig {
72    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
73        if deserializer.is_human_readable() {
74            deserializer.deserialize_str(IBigVisitor)
75        } else {
76            deserializer.deserialize_bytes(IBigVisitor)
77        }
78    }
79}
80
81/// IBig is serialized as two's complement little-endian bytes (matching `IBig::to_le_bytes`).
82struct IBigVisitor;
83
84impl<'de> Visitor<'de> for IBigVisitor {
85    type Value = IBig;
86
87    fn expecting(&self, f: &mut Formatter) -> fmt::Result {
88        write!(f, "a string or a sequence of bytes")
89    }
90
91    fn visit_str<E: de::Error>(self, v: &str) -> Result<Self::Value, E> {
92        match IBig::from_str_with_radix_prefix(v) {
93            Ok((n, _)) => Ok(n),
94            Err(e) => Err(de::Error::custom(e)),
95        }
96    }
97
98    fn visit_bytes<E: de::Error>(self, v: &[u8]) -> Result<Self::Value, E> {
99        Ok(IBig::from_le_bytes(v))
100    }
101}
dashu_int/third_party/serde.rs

dashu_int/third_party/
serde.rs
