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

use core::fmt;

use musli::en::{Encode, Encoder};
use musli::Context;

use crate::writer::Writer;

pub(crate) struct JsonObjectKeyEncoder<'a, W, C: ?Sized> {
    cx: &'a C,
    writer: W,
}

impl<'a, W, C: ?Sized> JsonObjectKeyEncoder<'a, W, C> {
    #[inline]
    pub(super) fn new(cx: &'a C, writer: W) -> Self {
        Self { cx, writer }
    }
}

macro_rules! format_integer {
    ($slf:ident, $value:ident) => {{
        $slf.writer.write_byte($slf.cx, b'"')?;
        let mut buffer = itoa::Buffer::new();
        $slf.writer
            .write_bytes($slf.cx, buffer.format($value).as_bytes())?;
        $slf.writer.write_byte($slf.cx, b'"')?;
        Ok(())
    }};
}

#[musli::encoder]
impl<'a, W, C> Encoder for JsonObjectKeyEncoder<'a, W, C>
where
    W: Writer,
    C: ?Sized + Context,
{
    type Cx = C;
    type Error = C::Error;
    type Ok = ();
    type Mode = C::Mode;
    type WithContext<'this, U> = JsonObjectKeyEncoder<'this, W, U> where U: 'this + Context;

    #[inline]
    fn cx(&self) -> &Self::Cx {
        self.cx
    }

    #[inline]
    fn with_context<U>(self, cx: &U) -> Result<Self::WithContext<'_, U>, C::Error>
    where
        U: Context,
    {
        Ok(JsonObjectKeyEncoder::new(cx, self.writer))
    }

    #[inline]
    fn expecting(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "any type that can be used as an object key")
    }

    #[inline]
    fn encode<T>(self, value: T) -> Result<Self::Ok, Self::Error>
    where
        T: Encode<Self::Mode>,
    {
        value.encode(self.cx, self)
    }

    #[inline]
    fn encode_u8(mut self, value: u8) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_u16(mut self, value: u16) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_u32(mut self, value: u32) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_u64(mut self, value: u64) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_u128(mut self, value: u128) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_i8(mut self, value: i8) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_i16(mut self, value: i16) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_i32(mut self, value: i32) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_i64(mut self, value: i64) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_i128(mut self, value: i128) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_usize(mut self, value: usize) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_isize(mut self, value: isize) -> Result<Self::Ok, C::Error> {
        format_integer!(self, value)
    }

    #[inline]
    fn encode_string(self, string: &str) -> Result<Self::Ok, C::Error> {
        super::encode_string(self.cx, self.writer, string.as_bytes())
    }

    #[inline]
    fn collect_string<T>(self, value: &T) -> Result<Self::Ok, <Self::Cx as Context>::Error>
    where
        T: ?Sized + fmt::Display,
    {
        let buf = self.cx.collect_string(value)?;
        self.encode_string(buf.as_ref())
    }
}