1 //! Serializing Rust structures into TOML.
2 //!
3 //! This module contains all the Serde support for serializing Rust structures into TOML.
4
5 mod array;
6 mod key;
7 mod map;
8 mod pretty;
9 mod value;
10
11 pub(crate) use array::*;
12 pub(crate) use key::*;
13 pub(crate) use map::*;
14
15 use crate::visit_mut::VisitMut;
16
17 /// Errors that can occur when deserializing a type.
18 #[derive(Debug, Clone, PartialEq, Eq)]
19 #[non_exhaustive]
20 pub enum Error {
21 /// Type could not be serialized to TOML
22 UnsupportedType(Option<&'static str>),
23 /// Value was out of range for the given type
24 OutOfRange(Option<&'static str>),
25 /// `None` could not be serialized to TOML
26 UnsupportedNone,
27 /// Key was not convertible to `String` for serializing to TOML
28 KeyNotString,
29 /// A serialized date was invalid
30 DateInvalid,
31 /// Other serialization error
32 Custom(String),
33 }
34
35 impl Error {
custom<T>(msg: T) -> Self where T: std::fmt::Display,36 pub(crate) fn custom<T>(msg: T) -> Self
37 where
38 T: std::fmt::Display,
39 {
40 Error::Custom(msg.to_string())
41 }
42 }
43
44 impl serde::ser::Error for Error {
custom<T>(msg: T) -> Self where T: std::fmt::Display,45 fn custom<T>(msg: T) -> Self
46 where
47 T: std::fmt::Display,
48 {
49 Self::custom(msg)
50 }
51 }
52
53 impl std::fmt::Display for Error {
fmt(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result54 fn fmt(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
55 match self {
56 Self::UnsupportedType(Some(t)) => write!(formatter, "unsupported {t} type"),
57 Self::UnsupportedType(None) => write!(formatter, "unsupported rust type"),
58 Self::OutOfRange(Some(t)) => write!(formatter, "out-of-range value for {t} type"),
59 Self::OutOfRange(None) => write!(formatter, "out-of-range value"),
60 Self::UnsupportedNone => "unsupported None value".fmt(formatter),
61 Self::KeyNotString => "map key was not a string".fmt(formatter),
62 Self::DateInvalid => "a serialized date was invalid".fmt(formatter),
63 Self::Custom(s) => s.fmt(formatter),
64 }
65 }
66 }
67
68 impl From<crate::TomlError> for Error {
from(e: crate::TomlError) -> Error69 fn from(e: crate::TomlError) -> Error {
70 Self::custom(e)
71 }
72 }
73
74 impl From<Error> for crate::TomlError {
from(e: Error) -> crate::TomlError75 fn from(e: Error) -> crate::TomlError {
76 Self::custom(e.to_string(), None)
77 }
78 }
79
80 impl std::error::Error for Error {}
81
82 /// Serialize the given data structure as a TOML byte vector.
83 ///
84 /// Serialization can fail if `T`'s implementation of `Serialize` decides to
85 /// fail, if `T` contains a map with non-string keys, or if `T` attempts to
86 /// serialize an unsupported datatype such as an enum, tuple, or tuple struct.
87 #[cfg(feature = "display")]
to_vec<T: ?Sized>(value: &T) -> Result<Vec<u8>, Error> where T: serde::ser::Serialize,88 pub fn to_vec<T: ?Sized>(value: &T) -> Result<Vec<u8>, Error>
89 where
90 T: serde::ser::Serialize,
91 {
92 to_string(value).map(|e| e.into_bytes())
93 }
94
95 /// Serialize the given data structure as a String of TOML.
96 ///
97 /// Serialization can fail if `T`'s implementation of `Serialize` decides to
98 /// fail, if `T` contains a map with non-string keys, or if `T` attempts to
99 /// serialize an unsupported datatype such as an enum, tuple, or tuple struct.
100 ///
101 /// # Examples
102 ///
103 /// ```
104 /// use serde::Serialize;
105 ///
106 /// #[derive(Serialize)]
107 /// struct Config {
108 /// database: Database,
109 /// }
110 ///
111 /// #[derive(Serialize)]
112 /// struct Database {
113 /// ip: String,
114 /// port: Vec<u16>,
115 /// connection_max: u32,
116 /// enabled: bool,
117 /// }
118 ///
119 /// let config = Config {
120 /// database: Database {
121 /// ip: "192.168.1.1".to_string(),
122 /// port: vec![8001, 8002, 8003],
123 /// connection_max: 5000,
124 /// enabled: false,
125 /// },
126 /// };
127 ///
128 /// let toml = toml_edit::ser::to_string(&config).unwrap();
129 /// println!("{}", toml)
130 /// ```
131 #[cfg(feature = "display")]
to_string<T: ?Sized>(value: &T) -> Result<String, Error> where T: serde::ser::Serialize,132 pub fn to_string<T: ?Sized>(value: &T) -> Result<String, Error>
133 where
134 T: serde::ser::Serialize,
135 {
136 to_document(value).map(|e| e.to_string())
137 }
138
139 /// Serialize the given data structure as a "pretty" String of TOML.
140 ///
141 /// This is identical to `to_string` except the output string has a more
142 /// "pretty" output. See `ValueSerializer::pretty` for more details.
143 #[cfg(feature = "display")]
to_string_pretty<T: ?Sized>(value: &T) -> Result<String, Error> where T: serde::ser::Serialize,144 pub fn to_string_pretty<T: ?Sized>(value: &T) -> Result<String, Error>
145 where
146 T: serde::ser::Serialize,
147 {
148 let mut document = to_document(value)?;
149 pretty::Pretty.visit_document_mut(&mut document);
150 Ok(document.to_string())
151 }
152
153 /// Serialize the given data structure into a TOML document.
154 ///
155 /// This would allow custom formatting to be applied, mixing with format preserving edits, etc.
to_document<T: ?Sized>(value: &T) -> Result<crate::Document, Error> where T: serde::ser::Serialize,156 pub fn to_document<T: ?Sized>(value: &T) -> Result<crate::Document, Error>
157 where
158 T: serde::ser::Serialize,
159 {
160 let value = value.serialize(ValueSerializer::new())?;
161 let item = crate::Item::Value(value);
162 let root = item
163 .into_table()
164 .map_err(|_| Error::UnsupportedType(None))?;
165 Ok(root.into())
166 }
167
168 pub use value::ValueSerializer;
169