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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
// Copyright 2017 Serde Developers
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

//! # Serde
//!
//! Serde is a framework for ***ser***ializing and ***de***serializing Rust data
//! structures efficiently and generically.
//!
//! The Serde ecosystem consists of data structures that know how to serialize
//! and deserialize themselves along with data formats that know how to
//! serialize and deserialize other things. Serde provides the layer by which
//! these two groups interact with each other, allowing any supported data
//! structure to be serialized and deserialized using any supported data format.
//!
//! See the Serde website [https://serde.rs/] for additional documentation and
//! usage examples.
//!
//! [https://serde.rs/]: https://serde.rs/
//!
//! ## Design
//!
//! Where many other languages rely on runtime reflection for serializing data,
//! Serde is instead built on Rust's powerful trait system. A data structure
//! that knows how to serialize and deserialize itself is one that implements
//! Serde's `Serialize` and `Deserialize` traits (or uses Serde's derive
//! attribute to automatically generate implementations at compile time). This
//! avoids any overhead of reflection or runtime type information. In fact in
//! many situations the interaction between data structure and data format can
//! be completely optimized away by the Rust compiler, leaving Serde
//! serialization to perform the same speed as a handwritten serializer for the
//! specific selection of data structure and data format.
//!
//! ## Data formats
//!
//! The following is a partial list of data formats that have been implemented
//! for Serde by the community.
//!
//! - [JSON], the ubiquitous JavaScript Object Notation used by many HTTP APIs.
//! - [Bincode], a compact binary format
//!   used for IPC within the Servo rendering engine.
//! - [CBOR], a Concise Binary Object Representation designed for small message
//!   size without the need for version negotiation.
//! - [YAML], a popular human-friendly configuration language that ain't markup
//!   language.
//! - [MessagePack], an efficient binary format that resembles a compact JSON.
//! - [TOML], a minimal configuration format used by [Cargo].
//! - [Pickle], a format common in the Python world.
//! - [Hjson], a variant of JSON designed to be readable and writable by humans.
//! - [BSON], the data storage and network transfer format used by MongoDB.
//! - [URL], the x-www-form-urlencoded format.
//! - [XML], the flexible machine-friendly W3C standard.
//!   *(deserialization only)*
//! - [Envy], a way to deserialize environment variables into Rust structs.
//!   *(deserialization only)*
//! - [Redis], deserialize values from Redis when using [redis-rs].
//!   *(deserialization only)*
//!
//! [JSON]: https://github.com/serde-rs/json
//! [Bincode]: https://github.com/TyOverby/bincode
//! [CBOR]: https://github.com/pyfisch/cbor
//! [YAML]: https://github.com/dtolnay/serde-yaml
//! [MessagePack]: https://github.com/3Hren/msgpack-rust
//! [TOML]: https://github.com/alexcrichton/toml-rs
//! [Pickle]: https://github.com/birkenfeld/serde-pickle
//! [Hjson]: https://github.com/laktak/hjson-rust
//! [BSON]: https://github.com/zonyitoo/bson-rs
//! [URL]: https://github.com/nox/serde_urlencoded
//! [XML]: https://github.com/RReverser/serde-xml-rs
//! [Envy]: https://github.com/softprops/envy
//! [Redis]: https://github.com/OneSignal/serde-redis
//! [Cargo]: http://doc.crates.io/manifest.html
//! [redis-rs]: https://crates.io/crates/redis

////////////////////////////////////////////////////////////////////////////////

// Serde types in rustdoc of other crates get linked to here.
#![doc(html_root_url = "https://docs.rs/serde/1.0.21")]

// Support using Serde without the standard library!
#![cfg_attr(not(feature = "std"), no_std)]

// Unstable functionality only if the user asks for it. For tracking and
// discussion of these features please refer to this issue:
//
//    https://github.com/serde-rs/serde/issues/812
#![cfg_attr(feature = "unstable", feature(nonzero, specialization))]
#![cfg_attr(feature = "alloc", feature(alloc))]

#![cfg_attr(feature = "cargo-clippy", deny(clippy, clippy_pedantic))]
// Whitelisted clippy lints
#![cfg_attr(feature = "cargo-clippy", allow(
    cast_lossless,
    const_static_lifetime,
    doc_markdown,
    linkedlist,
    needless_pass_by_value,
    type_complexity,
    unreadable_literal,
    zero_prefixed_literal,
))]
// Whitelisted clippy_pedantic lints
#![cfg_attr(feature = "cargo-clippy", allow(
// integer and float ser/de requires these sorts of casts
    cast_possible_truncation,
    cast_possible_wrap,
    cast_precision_loss,
    cast_sign_loss,
// simplifies some macros
    invalid_upcast_comparisons,
// things are often more readable this way
    option_unwrap_used,
    result_unwrap_used,
    shadow_reuse,
    single_match_else,
    stutter,
    use_self,
// not practical
    missing_docs_in_private_items,
// alternative is not stable
    empty_enum,
    use_debug,
))]

// Blacklisted Rust lints.
#![deny(missing_docs, unused_imports)]

////////////////////////////////////////////////////////////////////////////////

#[cfg(feature = "alloc")]
extern crate alloc;

#[cfg(all(feature = "unstable", feature = "std"))]
extern crate core;

/// A facade around all the types we need from the `std`, `core`, and `alloc`
/// crates. This avoids elaborate import wrangling having to happen in every
/// module.
mod lib {
    mod core {
        #[cfg(feature = "std")]
        pub use std::*;
        #[cfg(not(feature = "std"))]
        pub use core::*;
    }

    pub use self::core::{cmp, iter, mem, ops, slice, str};
    pub use self::core::{i8, i16, i32, i64, isize};
    pub use self::core::{u8, u16, u32, u64, usize};
    pub use self::core::{f32, f64};

    pub use self::core::cell::{Cell, RefCell};
    pub use self::core::clone::{self, Clone};
    pub use self::core::convert::{self, From, Into};
    pub use self::core::default::{self, Default};
    pub use self::core::fmt::{self, Debug, Display};
    pub use self::core::marker::{self, PhantomData};
    pub use self::core::option::{self, Option};
    pub use self::core::result::{self, Result};

    #[cfg(feature = "std")]
    pub use std::borrow::{Cow, ToOwned};
    #[cfg(all(feature = "alloc", not(feature = "std")))]
    pub use alloc::borrow::{Cow, ToOwned};

    #[cfg(feature = "std")]
    pub use std::string::String;
    #[cfg(all(feature = "alloc", not(feature = "std")))]
    pub use alloc::string::{String, ToString};

    #[cfg(feature = "std")]
    pub use std::vec::Vec;
    #[cfg(all(feature = "alloc", not(feature = "std")))]
    pub use alloc::vec::Vec;

    #[cfg(feature = "std")]
    pub use std::boxed::Box;
    #[cfg(all(feature = "alloc", not(feature = "std")))]
    pub use alloc::boxed::Box;

    #[cfg(all(feature = "rc", feature = "std"))]
    pub use std::rc::Rc;
    #[cfg(all(feature = "rc", feature = "alloc", not(feature = "std")))]
    pub use alloc::rc::Rc;

    #[cfg(all(feature = "rc", feature = "std"))]
    pub use std::sync::Arc;
    #[cfg(all(feature = "rc", feature = "alloc", not(feature = "std")))]
    pub use alloc::arc::Arc;

    #[cfg(feature = "std")]
    pub use std::collections::{BinaryHeap, BTreeMap, BTreeSet, LinkedList, VecDeque};
    #[cfg(all(feature = "alloc", not(feature = "std")))]
    pub use alloc::{BinaryHeap, BTreeMap, BTreeSet, LinkedList, VecDeque};

    #[cfg(feature = "std")]
    pub use std::{error, net};

    #[cfg(feature = "std")]
    pub use std::collections::{HashMap, HashSet};
    #[cfg(feature = "std")]
    pub use std::ffi::{CString, CStr, OsString, OsStr};
    #[cfg(feature = "std")]
    pub use std::hash::{Hash, BuildHasher};
    #[cfg(feature = "std")]
    pub use std::io::Write;
    #[cfg(feature = "std")]
    pub use std::num::Wrapping;
    #[cfg(feature = "std")]
    pub use std::path::{Path, PathBuf};
    #[cfg(feature = "std")]
    pub use std::time::{Duration, SystemTime, UNIX_EPOCH};
    #[cfg(feature = "std")]
    pub use std::sync::{Mutex, RwLock};

    #[cfg(feature = "unstable")]
    pub use core::nonzero::{NonZero, Zeroable};
}

////////////////////////////////////////////////////////////////////////////////

#[macro_use]
mod macros;

pub mod ser;
pub mod de;

#[doc(inline)]
pub use ser::{Serialize, Serializer};
#[doc(inline)]
pub use de::{Deserialize, Deserializer};

// Generated code uses these to support no_std. Not public API.
#[doc(hidden)]
pub mod export;

// Helpers used by generated code and doc tests. Not public API.
#[doc(hidden)]
pub mod private;

// Re-export #[derive(Serialize, Deserialize)].
//
// This is a workaround for https://github.com/rust-lang/cargo/issues/1286.
// Without this re-export, crates that put Serde derives behind a cfg_attr would
// need to use some silly feature name that depends on both serde and
// serde_derive.
//
//     [features]
//     serde-impls = ["serde", "serde_derive"]
//
//     [dependencies]
//     serde = { version = "1.0", optional = true }
//     serde_derive = { version = "1.0", optional = true }
//
//     # Used like this:
//     # #[cfg(feature = "serde-impls")]
//     # #[macro_use]
//     # extern crate serde_derive;
//     #
//     # #[cfg_attr(feature = "serde-impls", derive(Serialize, Deserialize))]
//     # struct S { /* ... */ }
//
// The re-exported derives allow crates to use "serde" as the name of their
// Serde feature which is more intuitive.
//
//     [dependencies]
//     serde = { version = "1.0", optional = true, features = ["derive"] }
//
//     # Used like this:
//     # #[cfg(feature = "serde")]
//     # #[macro_use]
//     # extern crate serde;
//     #
//     # #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
//     # struct S { /* ... */ }
//
// The reason re-exporting is not enabled by default is that disabling it would
// be annoying for crates that provide handwritten impls or data formats. They
// would need to disable default features and then explicitly re-enable std.
#[cfg(feature = "serde_derive")]
#[allow(unused_imports)]
#[macro_use]
extern crate serde_derive;
#[cfg(feature = "serde_derive")]
#[doc(hidden)]
pub use serde_derive::*;