serde/json.rs
2014-05-30 22:43:01 -07:00

4042 lines
130 KiB
Rust

// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// 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.
// Rust JSON serialization library
// Copyright (c) 2011 Google Inc.
#![forbid(non_camel_case_types)]
#![allow(missing_doc)]
/*!
JSON parsing and serialization
# What is JSON?
JSON (JavaScript Object Notation) is a way to write data in Javascript.
Like XML it allows one to encode structured data in a text format that can be read by humans easily.
Its native compatibility with JavaScript and its simple syntax make it used widely.
Json data are encoded in a form of "key":"value".
Data types that can be encoded are JavaScript types :
boolean (`true` or `false`), number (`f64`), string, array, object, null.
An object is a series of string keys mapping to values, in `"key": value` format.
Arrays are enclosed in square brackets ([ ... ]) and objects in curly brackets ({ ... }).
A simple JSON document encoding a person, his/her age, address and phone numbers could look like:
```ignore
{
"FirstName": "John",
"LastName": "Doe",
"Age": 43,
"Address": {
"Street": "Downing Street 10",
"City": "London",
"Country": "Great Britain"
},
"PhoneNumbers": [
"+44 1234567",
"+44 2345678"
]
}
```
# Rust Type-based Encoding and Decoding
Rust provides a mechanism for low boilerplate encoding & decoding
of values to and from JSON via the serialization API.
To be able to encode a piece of data, it must implement the `serialize::Encodable` trait.
To be able to decode a piece of data, it must implement the `serialize::Decodable` trait.
The Rust compiler provides an annotation to automatically generate
the code for these traits: `#[deriving(Decodable, Encodable)]`
To encode using Encodable :
```rust
use std::io;
use serialize::{json, Encodable};
#[deriving(Encodable)]
pub struct TestStruct {
data_str: String,
}
fn main() {
let to_encode_object = TestStruct{data_str:"example of string to encode".to_string()};
let mut m = io::MemWriter::new();
{
let mut encoder = json::Encoder::new(&mut m as &mut std::io::Writer);
match to_encode_object.encode(&mut encoder) {
Ok(()) => (),
Err(e) => fail!("json encoding error: {}", e)
};
}
}
```
Two wrapper functions are provided to encode a Encodable object
into a string (String) or buffer (~[u8]): `str_encode(&m)` and `buffer_encode(&m)`.
```rust
use serialize::json;
let to_encode_object = "example of string to encode".to_string();
let encoded_str: String = json::Encoder::str_encode(&to_encode_object);
```
JSON API provide an enum `json::Json` and a trait `ToJson` to encode object.
The trait `ToJson` encode object into a container `json::Json` and the API provide writer
to encode them into a stream or a string ...
When using `ToJson` the `Encodable` trait implementation is not mandatory.
A basic `ToJson` example using a TreeMap of attribute name / attribute value:
```rust
extern crate collections;
extern crate serialize;
use serialize::json;
use serialize::json::ToJson;
use collections::TreeMap;
pub struct MyStruct {
attr1: u8,
attr2: String,
}
impl ToJson for MyStruct {
fn to_json( &self ) -> json::Json {
let mut d = box TreeMap::new();
d.insert("attr1".to_string(), self.attr1.to_json());
d.insert("attr2".to_string(), self.attr2.to_json());
json::Object(d)
}
}
fn main() {
let test2: MyStruct = MyStruct {attr1: 1, attr2:"test".to_string()};
let tjson: json::Json = test2.to_json();
let json_str: String = tjson.to_str().into_string();
}
```
To decode a JSON string using `Decodable` trait :
```rust
extern crate serialize;
use serialize::{json, Decodable};
#[deriving(Decodable)]
pub struct MyStruct {
attr1: u8,
attr2: String,
}
fn main() {
let json_str_to_decode: String =
"{\"attr1\":1,\"attr2\":\"toto\"}".to_string();
let json_object = json::from_str(json_str_to_decode.as_slice());
let mut decoder = json::Decoder::new(json_object.unwrap());
let decoded_object: MyStruct = match Decodable::decode(&mut decoder) {
Ok(v) => v,
Err(e) => fail!("Decoding error: {}", e)
}; // create the final object
}
```
# Examples of use
## Using Autoserialization
Create a struct called TestStruct1 and serialize and deserialize it to and from JSON
using the serialization API, using the derived serialization code.
```rust
extern crate serialize;
use serialize::{json, Encodable, Decodable};
#[deriving(Decodable, Encodable)] //generate Decodable, Encodable impl.
pub struct TestStruct1 {
data_int: u8,
data_str: String,
data_vector: Vec<u8>,
}
// To serialize use the `json::str_encode` to encode an object in a string.
// It calls the generated `Encodable` impl.
fn main() {
let to_encode_object = TestStruct1
{data_int: 1, data_str:"toto".to_string(), data_vector:vec![2,3,4,5]};
let encoded_str: String = json::Encoder::str_encode(&to_encode_object);
// To deserialize use the `json::from_str` and `json::Decoder`
let json_object = json::from_str(encoded_str.as_slice());
let mut decoder = json::Decoder::new(json_object.unwrap());
let decoded1: TestStruct1 = Decodable::decode(&mut decoder).unwrap(); // create the final object
}
```
## Using `ToJson`
This example use the ToJson impl to deserialize the JSON string.
Example of `ToJson` trait implementation for TestStruct1.
```rust
extern crate serialize;
extern crate collections;
use serialize::json::ToJson;
use serialize::{json, Encodable, Decodable};
use collections::TreeMap;
#[deriving(Decodable, Encodable)] // generate Decodable, Encodable impl.
pub struct TestStruct1 {
data_int: u8,
data_str: String,
data_vector: Vec<u8>,
}
impl ToJson for TestStruct1 {
fn to_json( &self ) -> json::Json {
let mut d = box TreeMap::new();
d.insert("data_int".to_string(), self.data_int.to_json());
d.insert("data_str".to_string(), self.data_str.to_json());
d.insert("data_vector".to_string(), self.data_vector.to_json());
json::Object(d)
}
}
fn main() {
// Serialization using our impl of to_json
let test2: TestStruct1 = TestStruct1 {data_int: 1, data_str:"toto".to_string(),
data_vector:vec![2,3,4,5]};
let tjson: json::Json = test2.to_json();
let json_str: String = tjson.to_str().into_string();
// Deserialize like before.
let mut decoder =
json::Decoder::new(json::from_str(json_str.as_slice()).unwrap());
// create the final object
let decoded2: TestStruct1 = Decodable::decode(&mut decoder).unwrap();
}
```
*/
use std::char;
use std::f64;
use std::fmt;
use std::io::MemWriter;
use std::io;
use std::num;
use std::str::ScalarValue;
use std::str;
use std::string::String;
use std::vec::Vec;
use std::vec;
use de;
use collections::{Deque, HashMap, RingBuf, TreeMap};
use collections::treemap;
use serialize;
use serialize::{Encoder, Encodable};
/// Represents a json value
#[deriving(Clone, Eq, Show)]
pub enum Json {
Null,
Boolean(bool),
Number(f64),
String(String),
List(List),
Object(Object),
}
pub type List = Vec<Json>;
pub type Object = TreeMap<String, Json>;
impl<E, D: de::Deserializer<E>> de::Deserializable<E, D> for Json {
#[inline]
fn deserialize_token(d: &mut D, token: de::Token) -> Result<Json, E> {
match token {
de::Null => Ok(Null),
de::Bool(x) => Ok(Boolean(x)),
de::Int(x) => Ok(Number(x as f64)),
de::I8(x) => Ok(Number(x as f64)),
de::I16(x) => Ok(Number(x as f64)),
de::I32(x) => Ok(Number(x as f64)),
de::I64(x) => Ok(Number(x as f64)),
de::Uint(x) => Ok(Number(x as f64)),
de::U8(x) => Ok(Number(x as f64)),
de::U16(x) => Ok(Number(x as f64)),
de::U32(x) => Ok(Number(x as f64)),
de::U64(x) => Ok(Number(x as f64)),
de::F32(x) => Ok(Number(x as f64)),
de::F64(x) => Ok(Number(x)),
de::Char(x) => Ok(String(x.to_str())),
de::Str(x) => Ok(String(x.to_str())),
de::String(x) => Ok(String(x)),
de::Option(false) => Ok(Null),
de::Option(true) => de::Deserializable::deserialize(d),
de::TupleStart(_) | de::SeqStart(_) => {
let list = try!(de::Deserializable::deserialize_token(d, token));
Ok(List(list))
}
de::StructStart(_, _) | de::MapStart(_) => {
let object = try!(de::Deserializable::deserialize_token(d, token));
Ok(Object(object))
}
de::EnumStart(_, name, len) => {
let token = de::SeqStart(len);
let fields: Vec<Json> = try!(de::Deserializable::deserialize_token(d, token));
if fields.is_empty() {
Ok(String(name.to_string()))
} else {
let mut object = TreeMap::new();
object.insert("variant".to_string(), String(name.to_string()));
object.insert("fields".to_string(), List(fields));
Ok(Object(object))
}
}
de::End => Err(d.syntax_error()),
}
}
}
enum JsonDeserializerState {
JsonDeserializerValueState(Json),
JsonDeserializerListState(vec::MoveItems<Json>),
JsonDeserializerObjectState(treemap::MoveEntries<String, Json>),
JsonDeserializerEndState,
}
pub struct JsonDeserializer {
stack: Vec<JsonDeserializerState>,
}
impl JsonDeserializer {
/// Creates a new decoder instance for decoding the specified JSON value.
pub fn new(json: Json) -> JsonDeserializer {
JsonDeserializer {
stack: vec!(JsonDeserializerValueState(json)),
}
}
}
impl Iterator<Result<de::Token, ParserError>> for JsonDeserializer {
#[inline]
fn next(&mut self) -> Option<Result<de::Token, ParserError>> {
loop {
match self.stack.pop() {
Some(JsonDeserializerValueState(value)) => {
let token = match value {
Null => de::Null,
Boolean(x) => de::Bool(x),
Number(x) => de::F64(x),
String(x) => de::String(x),
List(x) => {
let len = x.len();
self.stack.push(JsonDeserializerListState(x.move_iter()));
de::SeqStart(len)
}
Object(x) => {
let len = x.len();
self.stack.push(JsonDeserializerObjectState(x.move_iter()));
de::MapStart(len)
}
};
return Some(Ok(token));
}
Some(JsonDeserializerListState(mut iter)) => {
match iter.next() {
Some(value) => {
self.stack.push(JsonDeserializerListState(iter));
self.stack.push(JsonDeserializerValueState(value));
// loop around.
}
None => {
return Some(Ok(de::End));
}
}
}
Some(JsonDeserializerObjectState(mut iter)) => {
match iter.next() {
Some((key, value)) => {
self.stack.push(JsonDeserializerObjectState(iter));
self.stack.push(JsonDeserializerValueState(value));
return Some(Ok(de::String(key)));
}
None => {
return Some(Ok(de::End));
}
}
}
Some(JsonDeserializerEndState) => {
return Some(Ok(de::End));
}
None => { return None; }
}
}
}
}
impl de::Deserializer<ParserError> for JsonDeserializer {
fn end_of_stream_error(&self) -> ParserError {
SyntaxError(EOFWhileParsingValue, 0, 0)
}
fn syntax_error(&self) -> ParserError {
SyntaxError(InvalidSyntax, 0, 0)
}
// Special case treating options as a nullable value.
#[inline]
fn expect_option<
U: de::Deserializable<ParserError, JsonDeserializer>
>(&mut self, token: de::Token) -> Result<Option<U>, ParserError> {
match token {
de::Null => Ok(None),
token => {
let value: U = try!(de::Deserializable::deserialize_token(self, token));
Ok(Some(value))
}
}
}
// Special case treating enums as a String or a `{"variant": "...", "fields": [...]}`.
#[inline]
fn expect_enum_start(&mut self,
token: de::Token,
_name: &str,
variants: &[&str]) -> Result<uint, ParserError> {
let variant = match token {
de::String(variant) => {
self.stack.push(JsonDeserializerEndState);
variant
}
de::MapStart(_) => {
let state = match self.stack.pop() {
Some(state) => state,
None => { fail!("state machine error, state stack empty"); }
};
let mut iter = match state {
JsonDeserializerObjectState(iter) => iter,
_ => { fail!("state machine error, expected an object"); }
};
let mut variant = None;
let mut fields = None;
for (key, value) in iter {
if key.equiv(&"variant") {
match value {
String(v) => { variant = Some(v); }
value => {
return Err(ExpectedError("String".to_string(),
format!("{}", value)))
}
}
} else if key.equiv(&"fields") {
match value {
List(v) => { fields = Some(v); }
value => {
return Err(ExpectedError("List".to_string(),
format!("{}", value)))
}
}
}
}
let (variant, fields) = match (variant, fields) {
(Some(variant), Some(fields)) => (variant, fields),
(None, _) => {
return Err(MissingFieldError("variant".to_string()))
}
(_, None) => {
return Err(MissingFieldError("fields".to_string()))
}
};
self.stack.push(JsonDeserializerEndState);
for field in fields.move_iter().rev() {
self.stack.push(JsonDeserializerValueState(field));
}
variant
}
token => {
return Err(ExpectedError("String or Object".to_string(),
format!("{}", token)))
}
};
match variants.iter().position(|v| *v == variant.as_slice()) {
Some(idx) => Ok(idx),
None => Err(UnknownVariantError(variant)),
}
}
}
/// The errors that can arise while parsing a JSON stream.
#[deriving(Clone, Eq)]
pub enum ErrorCode {
EOFWhileParsingList,
EOFWhileParsingObject,
EOFWhileParsingString,
EOFWhileParsingValue,
ExpectedColon,
InvalidEscape,
InvalidNumber,
InvalidSyntax,
InvalidUnicodeCodePoint,
KeyMustBeAString,
LoneLeadingSurrogateInHexEscape,
MissingField,
NotFourDigit,
NotUtf8,
TrailingCharacters,
UnexpectedEndOfHexEscape,
UnknownVariant,
UnrecognizedHex,
}
#[deriving(Clone, Eq, Show)]
pub enum ParserError {
/// msg, line, col
SyntaxError(ErrorCode, uint, uint),
IoError(io::IoErrorKind, &'static str),
ExpectedError(String, String),
MissingFieldError(String),
UnknownVariantError(String),
}
// Builder and Parser have the same errors.
pub type BuilderError = ParserError;
/*
#[deriving(Clone, Eq, Show)]
pub enum DecoderError {
ParseError(ParserError),
ExpectedError(String, String),
MissingFieldError(String),
UnknownVariantError(String),
}
*/
/// Returns a readable error string for a given error code.
pub fn error_str(error: ErrorCode) -> &'static str {
return match error {
EOFWhileParsingList => "EOF While parsing list",
EOFWhileParsingObject => "EOF While parsing object",
EOFWhileParsingString => "EOF While parsing string",
EOFWhileParsingValue => "EOF While parsing value",
ExpectedColon => "expected `:`",
InvalidEscape => "invalid escape",
InvalidNumber => "invalid number",
InvalidSyntax => "invalid syntax",
InvalidUnicodeCodePoint => "invalid unicode code point",
KeyMustBeAString => "key must be a string",
LoneLeadingSurrogateInHexEscape => "lone leading surrogate in hex escape",
MissingField => "missing variant",
NotFourDigit => "invalid \\u escape (not four digits)",
NotUtf8 => "contents not utf-8",
TrailingCharacters => "trailing characters",
UnexpectedEndOfHexEscape => "unexpected end of hex escape",
UnknownVariant => "unknown variant",
UnrecognizedHex => "invalid \\u escape (unrecognized hex)",
}
}
impl fmt::Show for ErrorCode {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
error_str(*self).fmt(f)
}
}
fn io_error_to_error(io: io::IoError) -> ParserError {
IoError(io.kind, io.desc)
}
pub type EncodeResult = io::IoResult<()>;
fn escape_str(s: &str) -> String {
let mut escaped = String::from_str("\"");
for c in s.chars() {
match c {
'"' => escaped.push_str("\\\""),
'\\' => escaped.push_str("\\\\"),
'\x08' => escaped.push_str("\\b"),
'\x0c' => escaped.push_str("\\f"),
'\n' => escaped.push_str("\\n"),
'\r' => escaped.push_str("\\r"),
'\t' => escaped.push_str("\\t"),
_ => escaped.push_char(c),
}
};
escaped.push_char('"');
escaped
}
fn spaces(n: uint) -> String {
let mut ss = String::new();
for _ in range(0, n) {
ss.push_str(" ");
}
return ss
}
/// A structure for implementing serialization to JSON.
pub struct Encoder<'a> {
wr: &'a mut io::Writer,
}
impl<'a> Encoder<'a> {
/// Creates a new JSON encoder whose output will be written to the writer
/// specified.
pub fn new<'a>(wr: &'a mut io::Writer) -> Encoder<'a> {
Encoder { wr: wr }
}
/// Encode the specified struct into a json [u8]
pub fn buffer_encode<
T: serialize::Encodable<Encoder<'a>,
io::IoError>
>(to_encode_object: &T) -> Vec<u8> {
//Serialize the object in a string using a writer
let mut m = MemWriter::new();
{
let mut encoder = Encoder::new(&mut m as &mut io::Writer);
// MemWriter never Errs
let _ = to_encode_object.encode(&mut encoder);
}
m.unwrap()
}
/// Encode the specified struct into a json str
pub fn str_encode<
T: serialize::Encodable<Encoder<'a>,
io::IoError>
>(to_encode_object: &T) -> String {
let buff = Encoder::buffer_encode(to_encode_object);
str::from_utf8(buff.as_slice()).unwrap().to_string()
}
}
impl<'a> serialize::Encoder<io::IoError> for Encoder<'a> {
fn emit_nil(&mut self) -> EncodeResult { write!(self.wr, "null") }
fn emit_uint(&mut self, v: uint) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u64(&mut self, v: u64) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u32(&mut self, v: u32) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u16(&mut self, v: u16) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u8(&mut self, v: u8) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_int(&mut self, v: int) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i64(&mut self, v: i64) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i32(&mut self, v: i32) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i16(&mut self, v: i16) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i8(&mut self, v: i8) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_bool(&mut self, v: bool) -> EncodeResult {
if v {
write!(self.wr, "true")
} else {
write!(self.wr, "false")
}
}
fn emit_f64(&mut self, v: f64) -> EncodeResult {
write!(self.wr, "{}", f64::to_str_digits(v, 6u))
}
fn emit_f32(&mut self, v: f32) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_char(&mut self, v: char) -> EncodeResult {
self.emit_str(str::from_char(v).as_slice())
}
fn emit_str(&mut self, v: &str) -> EncodeResult {
write!(self.wr, "{}", escape_str(v))
}
fn emit_enum(&mut self,
_name: &str,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult { f(self) }
fn emit_enum_variant(&mut self,
name: &str,
_id: uint,
cnt: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
// enums are encoded as strings or objects
// Bunny => "Bunny"
// Kangaroo(34,"William") => {"variant": "Kangaroo", "fields": [34,"William"]}
if cnt == 0 {
write!(self.wr, "{}", escape_str(name))
} else {
try!(write!(self.wr, "\\{\"variant\":"));
try!(write!(self.wr, "{}", escape_str(name)));
try!(write!(self.wr, ",\"fields\":["));
try!(f(self));
write!(self.wr, "]\\}")
}
}
fn emit_enum_variant_arg(&mut self,
idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
if idx != 0 {
try!(write!(self.wr, ","));
}
f(self)
}
fn emit_enum_struct_variant(&mut self,
name: &str,
id: uint,
cnt: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_enum_variant(name, id, cnt, f)
}
fn emit_enum_struct_variant_field(&mut self,
_: &str,
idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_enum_variant_arg(idx, f)
}
fn emit_struct(&mut self,
_: &str,
_: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
try!(write!(self.wr, r"\{"));
try!(f(self));
write!(self.wr, r"\}")
}
fn emit_struct_field(&mut self,
name: &str,
idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
if idx != 0 { try!(write!(self.wr, ",")); }
try!(write!(self.wr, "{}:", escape_str(name)));
f(self)
}
fn emit_tuple(&mut self, len: uint, f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq(len, f)
}
fn emit_tuple_arg(&mut self,
idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq_elt(idx, f)
}
fn emit_tuple_struct(&mut self,
_name: &str,
len: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq(len, f)
}
fn emit_tuple_struct_arg(&mut self,
idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq_elt(idx, f)
}
fn emit_option(&mut self, f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
f(self)
}
fn emit_option_none(&mut self) -> EncodeResult { self.emit_nil() }
fn emit_option_some(&mut self, f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
f(self)
}
fn emit_seq(&mut self, _len: uint, f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
try!(write!(self.wr, "["));
try!(f(self));
write!(self.wr, "]")
}
fn emit_seq_elt(&mut self, idx: uint, f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
if idx != 0 {
try!(write!(self.wr, ","));
}
f(self)
}
fn emit_map(&mut self, _len: uint, f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
try!(write!(self.wr, r"\{"));
try!(f(self));
write!(self.wr, r"\}")
}
fn emit_map_elt_key(&mut self,
idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
use std::str::from_utf8;
if idx != 0 { try!(write!(self.wr, ",")) }
// ref #12967, make sure to wrap a key in double quotes,
// in the event that its of a type that omits them (eg numbers)
let mut buf = MemWriter::new();
let mut check_encoder = Encoder::new(&mut buf);
try!(f(&mut check_encoder));
let buf = buf.unwrap();
let out = from_utf8(buf.as_slice()).unwrap();
let needs_wrapping = out.char_at(0) != '"' &&
out.char_at_reverse(out.len()) != '"';
if needs_wrapping { try!(write!(self.wr, "\"")); }
try!(f(self));
if needs_wrapping { try!(write!(self.wr, "\"")); }
Ok(())
}
fn emit_map_elt_val(&mut self,
_idx: uint,
f: |&mut Encoder<'a>| -> EncodeResult) -> EncodeResult {
try!(write!(self.wr, ":"));
f(self)
}
}
/// Another encoder for JSON, but prints out human-readable JSON instead of
/// compact data
pub struct PrettyEncoder<'a> {
wr: &'a mut io::Writer,
indent: uint,
}
impl<'a> PrettyEncoder<'a> {
/// Creates a new encoder whose output will be written to the specified writer
pub fn new<'a>(wr: &'a mut io::Writer) -> PrettyEncoder<'a> {
PrettyEncoder {
wr: wr,
indent: 0,
}
}
}
impl<'a> serialize::Encoder<io::IoError> for PrettyEncoder<'a> {
fn emit_nil(&mut self) -> EncodeResult { write!(self.wr, "null") }
fn emit_uint(&mut self, v: uint) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u64(&mut self, v: u64) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u32(&mut self, v: u32) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u16(&mut self, v: u16) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_u8(&mut self, v: u8) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_int(&mut self, v: int) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i64(&mut self, v: i64) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i32(&mut self, v: i32) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i16(&mut self, v: i16) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_i8(&mut self, v: i8) -> EncodeResult { self.emit_f64(v as f64) }
fn emit_bool(&mut self, v: bool) -> EncodeResult {
if v {
write!(self.wr, "true")
} else {
write!(self.wr, "false")
}
}
fn emit_f64(&mut self, v: f64) -> EncodeResult {
write!(self.wr, "{}", f64::to_str_digits(v, 6u))
}
fn emit_f32(&mut self, v: f32) -> EncodeResult {
self.emit_f64(v as f64)
}
fn emit_char(&mut self, v: char) -> EncodeResult {
self.emit_str(str::from_char(v).as_slice())
}
fn emit_str(&mut self, v: &str) -> EncodeResult {
write!(self.wr, "{}", escape_str(v))
}
fn emit_enum(&mut self,
_name: &str,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
f(self)
}
fn emit_enum_variant(&mut self,
name: &str,
_: uint,
cnt: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if cnt == 0 {
write!(self.wr, "{}", escape_str(name))
} else {
self.indent += 2;
try!(write!(self.wr, "[\n{}{},\n", spaces(self.indent),
escape_str(name)));
try!(f(self));
self.indent -= 2;
write!(self.wr, "\n{}]", spaces(self.indent))
}
}
fn emit_enum_variant_arg(&mut self,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if idx != 0 {
try!(write!(self.wr, ",\n"));
}
try!(write!(self.wr, "{}", spaces(self.indent)));
f(self)
}
fn emit_enum_struct_variant(&mut self,
name: &str,
id: uint,
cnt: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_enum_variant(name, id, cnt, f)
}
fn emit_enum_struct_variant_field(&mut self,
_: &str,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_enum_variant_arg(idx, f)
}
fn emit_struct(&mut self,
_: &str,
len: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if len == 0 {
write!(self.wr, "\\{\\}")
} else {
try!(write!(self.wr, "\\{"));
self.indent += 2;
try!(f(self));
self.indent -= 2;
write!(self.wr, "\n{}\\}", spaces(self.indent))
}
}
fn emit_struct_field(&mut self,
name: &str,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if idx == 0 {
try!(write!(self.wr, "\n"));
} else {
try!(write!(self.wr, ",\n"));
}
try!(write!(self.wr, "{}{}: ", spaces(self.indent), escape_str(name)));
f(self)
}
fn emit_tuple(&mut self,
len: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq(len, f)
}
fn emit_tuple_arg(&mut self,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq_elt(idx, f)
}
fn emit_tuple_struct(&mut self,
_: &str,
len: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq(len, f)
}
fn emit_tuple_struct_arg(&mut self,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
self.emit_seq_elt(idx, f)
}
fn emit_option(&mut self, f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
f(self)
}
fn emit_option_none(&mut self) -> EncodeResult { self.emit_nil() }
fn emit_option_some(&mut self, f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
f(self)
}
fn emit_seq(&mut self,
len: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if len == 0 {
write!(self.wr, "[]")
} else {
try!(write!(self.wr, "["));
self.indent += 2;
try!(f(self));
self.indent -= 2;
write!(self.wr, "\n{}]", spaces(self.indent))
}
}
fn emit_seq_elt(&mut self,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if idx == 0 {
try!(write!(self.wr, "\n"));
} else {
try!(write!(self.wr, ",\n"));
}
try!(write!(self.wr, "{}", spaces(self.indent)));
f(self)
}
fn emit_map(&mut self,
len: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
if len == 0 {
write!(self.wr, "\\{\\}")
} else {
try!(write!(self.wr, "\\{"));
self.indent += 2;
try!(f(self));
self.indent -= 2;
write!(self.wr, "\n{}\\}", spaces(self.indent))
}
}
fn emit_map_elt_key(&mut self,
idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
use std::str::from_utf8;
if idx == 0 {
try!(write!(self.wr, "\n"));
} else {
try!(write!(self.wr, ",\n"));
}
try!(write!(self.wr, "{}", spaces(self.indent)));
// ref #12967, make sure to wrap a key in double quotes,
// in the event that its of a type that omits them (eg numbers)
let mut buf = MemWriter::new();
let mut check_encoder = PrettyEncoder::new(&mut buf);
try!(f(&mut check_encoder));
let buf = buf.unwrap();
let out = from_utf8(buf.as_slice()).unwrap();
let needs_wrapping = out.char_at(0) != '"' &&
out.char_at_reverse(out.len()) != '"';
if needs_wrapping { try!(write!(self.wr, "\"")); }
try!(f(self));
if needs_wrapping { try!(write!(self.wr, "\"")); }
Ok(())
}
fn emit_map_elt_val(&mut self,
_idx: uint,
f: |&mut PrettyEncoder<'a>| -> EncodeResult) -> EncodeResult {
try!(write!(self.wr, ": "));
f(self)
}
}
impl<E: serialize::Encoder<S>, S> serialize::Encodable<E, S> for Json {
fn encode(&self, e: &mut E) -> Result<(), S> {
match *self {
Number(v) => v.encode(e),
String(ref v) => v.encode(e),
Boolean(v) => v.encode(e),
List(ref v) => v.encode(e),
Object(ref v) => v.encode(e),
Null => e.emit_nil(),
}
}
}
impl Json {
/// Encodes a json value into an io::writer. Uses a single line.
pub fn to_writer(&self, wr: &mut io::Writer) -> EncodeResult {
let mut encoder = Encoder::new(wr);
self.encode(&mut encoder)
}
/// Encodes a json value into an io::writer.
/// Pretty-prints in a more readable format.
pub fn to_pretty_writer(&self, wr: &mut io::Writer) -> EncodeResult {
let mut encoder = PrettyEncoder::new(wr);
self.encode(&mut encoder)
}
/// Encodes a json value into a string
pub fn to_pretty_str(&self) -> String {
let mut s = MemWriter::new();
self.to_pretty_writer(&mut s as &mut io::Writer).unwrap();
str::from_utf8(s.unwrap().as_slice()).unwrap().to_string()
}
/// If the Json value is an Object, returns the value associated with the provided key.
/// Otherwise, returns None.
pub fn find<'a>(&'a self, key: &String) -> Option<&'a Json>{
match self {
&Object(ref map) => map.find(key),
_ => None
}
}
/// Attempts to get a nested Json Object for each key in `keys`.
/// If any key is found not to exist, find_path will return None.
/// Otherwise, it will return the Json value associated with the final key.
pub fn find_path<'a>(&'a self, keys: &[&String]) -> Option<&'a Json>{
let mut target = self;
for key in keys.iter() {
match target.find(*key) {
Some(t) => { target = t; },
None => return None
}
}
Some(target)
}
/// If the Json value is an Object, performs a depth-first search until
/// a value associated with the provided key is found. If no value is found
/// or the Json value is not an Object, returns None.
pub fn search<'a>(&'a self, key: &String) -> Option<&'a Json> {
match self {
&Object(ref map) => {
match map.find(key) {
Some(json_value) => Some(json_value),
None => {
let mut value : Option<&'a Json> = None;
for (_, v) in map.iter() {
value = v.search(key);
if value.is_some() {
break;
}
}
value
}
}
},
_ => None
}
}
/// Returns true if the Json value is an Object. Returns false otherwise.
pub fn is_object<'a>(&'a self) -> bool {
self.as_object().is_some()
}
/// If the Json value is an Object, returns the associated TreeMap.
/// Returns None otherwise.
pub fn as_object<'a>(&'a self) -> Option<&'a Object> {
match *self {
Object(ref map) => Some(map),
_ => None
}
}
/// Returns true if the Json value is a List. Returns false otherwise.
pub fn is_list<'a>(&'a self) -> bool {
self.as_list().is_some()
}
/// If the Json value is a List, returns the associated vector.
/// Returns None otherwise.
pub fn as_list<'a>(&'a self) -> Option<&'a List> {
match *self {
List(ref list) => Some(list),
_ => None
}
}
/// Returns true if the Json value is a String. Returns false otherwise.
pub fn is_string<'a>(&'a self) -> bool {
self.as_string().is_some()
}
/// If the Json value is a String, returns the associated str.
/// Returns None otherwise.
pub fn as_string<'a>(&'a self) -> Option<&'a str> {
match *self {
String(ref s) => Some(s.as_slice()),
_ => None
}
}
/// Returns true if the Json value is a Number. Returns false otherwise.
pub fn is_number(&self) -> bool {
self.as_number().is_some()
}
/// If the Json value is a Number, returns the associated f64.
/// Returns None otherwise.
pub fn as_number(&self) -> Option<f64> {
match *self {
Number(n) => Some(n),
_ => None
}
}
/// Returns true if the Json value is a Boolean. Returns false otherwise.
pub fn is_boolean(&self) -> bool {
self.as_boolean().is_some()
}
/// If the Json value is a Boolean, returns the associated bool.
/// Returns None otherwise.
pub fn as_boolean(&self) -> Option<bool> {
match *self {
Boolean(b) => Some(b),
_ => None
}
}
/// Returns true if the Json value is a Null. Returns false otherwise.
pub fn is_null(&self) -> bool {
self.as_null().is_some()
}
/// If the Json value is a Null, returns ().
/// Returns None otherwise.
pub fn as_null(&self) -> Option<()> {
match *self {
Null => Some(()),
_ => None
}
}
}
/*
/// The output of the streaming parser.
#[deriving(Eq, Clone, Show)]
pub enum JsonEvent {
ObjectStart,
ObjectEnd,
ListStart,
ListEnd,
BooleanValue(bool),
NumberValue(f64),
StringValue(String),
NullValue,
Error(ParserError),
}
*/
#[deriving(Eq, Show)]
enum ParserState {
// Parse a value.
ParseValue,
// Parse a value or ']'.
ParseListStart,
// Parse ',' or ']' after an element in a list.
ParseListCommaOrEnd,
// Parse a key:value or an ']'.
ParseObjectStart,
// Parse ',' or ']' after an element in an object.
ParseObjectCommaOrEnd,
// Parse a key in an object.
ParseObjectKey,
// Parse a value in an object.
ParseObjectValue,
}
/*
/// A Stack represents the current position of the parser in the logical
/// structure of the JSON stream.
/// For example foo.bar[3].x
pub struct Stack {
stack: Vec<InternalStackElement>,
str_buffer: Vec<u8>,
}
/// StackElements compose a Stack.
/// For example, Key("foo"), Key("bar"), Index(3) and Key("x") are the
/// StackElements compositing the stack that represents foo.bar[3].x
#[deriving(Eq, Clone, Show)]
pub enum StackElement<'l> {
Index(u32),
Key(&'l str),
}
// Internally, Key elements are stored as indices in a buffer to avoid
// allocating a string for every member of an object.
#[deriving(Eq, Clone, Show)]
enum InternalStackElement {
InternalIndex(u32),
InternalKey(u16, u16), // start, size
}
impl Stack {
pub fn new() -> Stack {
Stack {
stack: Vec::new(),
str_buffer: Vec::new(),
}
}
/// Returns The number of elements in the Stack.
pub fn len(&self) -> uint { self.stack.len() }
/// Returns true if the stack is empty, equivalent to self.len() == 0.
pub fn is_empty(&self) -> bool { self.stack.len() == 0 }
/// Provides access to the StackElement at a given index.
/// lower indices are at the bottom of the stack while higher indices are
/// at the top.
pub fn get<'l>(&'l self, idx: uint) -> StackElement<'l> {
return match *self.stack.get(idx) {
InternalIndex(i) => { Index(i) }
InternalKey(start, size) => {
Key(str::from_utf8(self.str_buffer.slice(start as uint, (start+size) as uint)).unwrap())
}
}
}
/// Compares this stack with an array of StackElements.
pub fn is_equal_to(&self, rhs: &[StackElement]) -> bool {
if self.stack.len() != rhs.len() { return false; }
for i in range(0, rhs.len()) {
if self.get(i) != rhs[i] { return false; }
}
return true;
}
/// Returns true if the bottom-most elements of this stack are the same as
/// the ones passed as parameter.
pub fn starts_with(&self, rhs: &[StackElement]) -> bool {
if self.stack.len() < rhs.len() { return false; }
for i in range(0, rhs.len()) {
if self.get(i) != rhs[i] { return false; }
}
return true;
}
/// Returns true if the top-most elements of this stack are the same as
/// the ones passed as parameter.
pub fn ends_with(&self, rhs: &[StackElement]) -> bool {
if self.stack.len() < rhs.len() { return false; }
let offset = self.stack.len() - rhs.len();
for i in range(0, rhs.len()) {
if self.get(i + offset) != rhs[i] { return false; }
}
return true;
}
/// Returns the top-most element (if any).
pub fn top<'l>(&'l self) -> Option<StackElement<'l>> {
return match self.stack.last() {
None => None,
Some(&InternalIndex(i)) => Some(Index(i)),
Some(&InternalKey(start, size)) => {
Some(Key(str::from_utf8(
self.str_buffer.slice(start as uint, (start+size) as uint)
).unwrap()))
}
}
}
// Used by Parser to insert Key elements at the top of the stack.
fn push_key(&mut self, key: String) {
self.stack.push(InternalKey(self.str_buffer.len() as u16, key.len() as u16));
for c in key.as_bytes().iter() {
self.str_buffer.push(*c);
}
}
// Used by Parser to insert Index elements at the top of the stack.
fn push_index(&mut self, index: u32) {
self.stack.push(InternalIndex(index));
}
// Used by Parser to remove the top-most element of the stack.
fn pop(&mut self) {
assert!(!self.is_empty());
match *self.stack.last().unwrap() {
InternalKey(_, sz) => {
let new_size = self.str_buffer.len() - sz as uint;
unsafe {
self.str_buffer.set_len(new_size);
}
}
InternalIndex(_) => {}
}
self.stack.pop();
}
// Used by Parser to test whether the top-most element is an index.
fn last_is_index(&self) -> bool {
if self.is_empty() { return false; }
return match *self.stack.last().unwrap() {
InternalIndex(_) => true,
_ => false,
}
}
// Used by Parser to increment the index of the top-most element.
fn bump_index(&mut self) {
let len = self.stack.len();
let idx = match *self.stack.last().unwrap() {
InternalIndex(i) => { i + 1 }
_ => { fail!(); }
};
*self.stack.get_mut(len - 1) = InternalIndex(idx);
}
}
*/
/// A streaming JSON parser implemented as an iterator of JsonEvent, consuming
/// an iterator of char.
pub struct Parser<T> {
rdr: T,
ch: Option<char>,
line: uint,
col: uint,
// A state machine is kept to make it possible to interupt and resume parsing.
state: Vec<ParserState>,
tokens: RingBuf<de::Token>,
}
impl<T: Iterator<char>> Iterator<Result<de::Token, ParserError>> for Parser<T> {
#[inline]
fn next(&mut self) -> Option<Result<de::Token, ParserError>> {
// If we've cached any tokens return them now.
match self.tokens.pop_front() {
Some(token) => { return Some(Ok(token)); }
None => { }
}
let state = match self.state.pop() {
Some(state) => state,
None => {
// If we have no state left, then we're expecting the structure
// to be done, so make sure there are no trailing characters.
self.parse_whitespace();
if self.eof() {
return None;
} else {
return Some(self.error(TrailingCharacters));
}
}
};
match state {
ParseValue => Some(self.parse_value()),
ParseListStart => Some(self.parse_list_start()),
ParseListCommaOrEnd => Some(self.parse_list_comma_or_end()),
ParseObjectStart => Some(self.parse_object_start()),
ParseObjectCommaOrEnd => Some(self.parse_object_comma_or_end()),
ParseObjectKey => Some(self.parse_object_key()),
ParseObjectValue => Some(self.parse_object_value()),
}
}
}
impl<T: Iterator<char>> Parser<T> {
/// Creates the JSON parser.
pub fn new(rdr: T) -> Parser<T> {
let mut p = Parser {
rdr: rdr,
ch: Some('\x00'),
line: 1,
col: 0,
state: vec!(ParseValue),
tokens: RingBuf::new(),
};
p.bump();
return p;
}
fn eof(&self) -> bool { self.ch.is_none() }
fn ch_or_null(&self) -> char { self.ch.unwrap_or('\x00') }
fn bump(&mut self) {
self.ch = self.rdr.next();
if self.ch_is('\n') {
self.line += 1;
self.col = 1;
} else {
self.col += 1;
}
}
fn next_char(&mut self) -> Option<char> {
self.bump();
self.ch
}
fn ch_is(&self, c: char) -> bool {
self.ch == Some(c)
}
fn error<T>(&self, reason: ErrorCode) -> Result<T, ParserError> {
Err(SyntaxError(reason, self.line, self.col))
}
fn parse_whitespace(&mut self) {
while self.ch_is(' ') ||
self.ch_is('\n') ||
self.ch_is('\t') ||
self.ch_is('\r') { self.bump(); }
}
fn parse_number(&mut self) -> Result<f64, ParserError> {
let mut neg = 1.0;
if self.ch_is('-') {
self.bump();
neg = -1.0;
}
let mut res = match self.parse_integer() {
Ok(res) => res,
Err(e) => return Err(e)
};
if self.ch_is('.') {
match self.parse_decimal(res) {
Ok(r) => res = r,
Err(e) => return Err(e)
}
}
if self.ch_is('e') || self.ch_is('E') {
match self.parse_exponent(res) {
Ok(r) => res = r,
Err(e) => return Err(e)
}
}
Ok(neg * res)
}
fn parse_integer(&mut self) -> Result<f64, ParserError> {
let mut res = 0.0;
match self.ch_or_null() {
'0' => {
self.bump();
// There can be only one leading '0'.
match self.ch_or_null() {
'0' .. '9' => return self.error(InvalidNumber),
_ => ()
}
},
'1' .. '9' => {
while !self.eof() {
match self.ch_or_null() {
c @ '0' .. '9' => {
res *= 10.0;
res += ((c as int) - ('0' as int)) as f64;
self.bump();
}
_ => break,
}
}
}
_ => return self.error(InvalidNumber),
}
Ok(res)
}
fn parse_decimal(&mut self, res: f64) -> Result<f64, ParserError> {
self.bump();
// Make sure a digit follows the decimal place.
match self.ch_or_null() {
'0' .. '9' => (),
_ => return self.error(InvalidNumber)
}
let mut res = res;
let mut dec = 1.0;
while !self.eof() {
match self.ch_or_null() {
c @ '0' .. '9' => {
dec /= 10.0;
res += (((c as int) - ('0' as int)) as f64) * dec;
self.bump();
}
_ => break,
}
}
Ok(res)
}
fn parse_exponent(&mut self, mut res: f64) -> Result<f64, ParserError> {
self.bump();
let mut exp = 0u;
let mut neg_exp = false;
if self.ch_is('+') {
self.bump();
} else if self.ch_is('-') {
self.bump();
neg_exp = true;
}
// Make sure a digit follows the exponent place.
match self.ch_or_null() {
'0' .. '9' => (),
_ => return self.error(InvalidNumber)
}
while !self.eof() {
match self.ch_or_null() {
c @ '0' .. '9' => {
exp *= 10;
exp += (c as uint) - ('0' as uint);
self.bump();
}
_ => break
}
}
let exp: f64 = num::pow(10u as f64, exp);
if neg_exp {
res /= exp;
} else {
res *= exp;
}
Ok(res)
}
fn decode_hex_escape(&mut self) -> Result<u16, ParserError> {
let mut i = 0u;
let mut n = 0u16;
while i < 4u && !self.eof() {
self.bump();
n = match self.ch_or_null() {
c @ '0' .. '9' => n * 16_u16 + ((c as u16) - ('0' as u16)),
'a' | 'A' => n * 16_u16 + 10_u16,
'b' | 'B' => n * 16_u16 + 11_u16,
'c' | 'C' => n * 16_u16 + 12_u16,
'd' | 'D' => n * 16_u16 + 13_u16,
'e' | 'E' => n * 16_u16 + 14_u16,
'f' | 'F' => n * 16_u16 + 15_u16,
_ => return self.error(InvalidEscape)
};
i += 1u;
}
// Error out if we didn't parse 4 digits.
if i != 4u {
return self.error(InvalidEscape);
}
Ok(n)
}
fn parse_str(&mut self) -> Result<String, ParserError> {
let mut escape = false;
let mut res = String::new();
loop {
self.bump();
if self.eof() {
return self.error(EOFWhileParsingString);
}
if escape {
match self.ch_or_null() {
'"' => res.push_char('"'),
'\\' => res.push_char('\\'),
'/' => res.push_char('/'),
'b' => res.push_char('\x08'),
'f' => res.push_char('\x0c'),
'n' => res.push_char('\n'),
'r' => res.push_char('\r'),
't' => res.push_char('\t'),
'u' => match try!(self.decode_hex_escape()) {
0xDC00 .. 0xDFFF => return self.error(LoneLeadingSurrogateInHexEscape),
// Non-BMP characters are encoded as a sequence of
// two hex escapes, representing UTF-16 surrogates.
n1 @ 0xD800 .. 0xDBFF => {
let c1 = self.next_char();
let c2 = self.next_char();
match (c1, c2) {
(Some('\\'), Some('u')) => (),
_ => return self.error(UnexpectedEndOfHexEscape),
}
let buf = [n1, try!(self.decode_hex_escape())];
match str::utf16_items(buf.as_slice()).next() {
Some(ScalarValue(c)) => res.push_char(c),
_ => return self.error(LoneLeadingSurrogateInHexEscape),
}
}
n => match char::from_u32(n as u32) {
Some(c) => res.push_char(c),
None => return self.error(InvalidUnicodeCodePoint),
},
},
_ => return self.error(InvalidEscape),
}
escape = false;
} else if self.ch_is('\\') {
escape = true;
} else {
match self.ch {
Some('"') => {
self.bump();
return Ok(res);
},
Some(c) => res.push_char(c),
None => unreachable!()
}
}
}
}
fn parse_list_start(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
if self.ch_is(']') {
self.bump();
Ok(de::End)
} else {
self.state.push(ParseListCommaOrEnd);
self.parse_value()
}
}
fn parse_list_comma_or_end(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
if self.ch_is(',') {
self.bump();
self.state.push(ParseListCommaOrEnd);
self.parse_value()
} else if self.ch_is(']') {
self.bump();
Ok(de::End)
} else if self.eof() {
self.error_event(EOFWhileParsingList)
} else {
self.error_event(InvalidSyntax)
}
}
fn parse_object_start(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
if self.ch_is('}') {
self.bump();
Ok(de::End)
} else {
self.parse_object_key()
}
}
fn parse_object_comma_or_end(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
if self.ch_is(',') {
self.bump();
self.parse_object_key()
} else if self.ch_is('}') {
self.bump();
Ok(de::End)
} else if self.eof() {
self.error_event(EOFWhileParsingObject)
} else {
self.error_event(InvalidSyntax)
}
}
fn parse_object_key(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
self.state.push(ParseObjectValue);
if self.eof() {
return self.error_event(EOFWhileParsingString);
}
match self.ch_or_null() {
'"' => {
let s = try!(self.parse_str());
Ok(de::String(s))
}
_ => self.error_event(KeyMustBeAString),
}
}
fn parse_object_value(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
if self.ch_is(':') {
self.bump();
self.state.push(ParseObjectCommaOrEnd);
self.parse_value()
} else if self.eof() {
self.error_event(EOFWhileParsingObject)
} else {
self.error_event(ExpectedColon)
}
}
fn parse_value(&mut self) -> Result<de::Token, ParserError> {
self.parse_whitespace();
if self.eof() {
return self.error_event(EOFWhileParsingValue);
}
match self.ch_or_null() {
'n' => self.parse_ident("ull", de::Null),
't' => self.parse_ident("rue", de::Bool(true)),
'f' => self.parse_ident("alse", de::Bool(false)),
'0' .. '9' | '-' => {
let number = try!(self.parse_number());
Ok(de::F64(number))
}
'"' => {
let s = try!(self.parse_str());
Ok(de::String(s))
}
'[' => {
self.bump();
self.state.push(ParseListStart);
Ok(de::SeqStart(0))
}
'{' => {
self.bump();
self.state.push(ParseObjectStart);
Ok(de::MapStart(0))
}
_ => {
self.error_event(InvalidSyntax)
}
}
}
fn parse_ident(&mut self, ident: &str, value: de::Token) -> Result<de::Token, ParserError> {
if ident.chars().all(|c| Some(c) == self.next_char()) {
self.bump();
Ok(value)
} else {
Err(SyntaxError(InvalidSyntax, self.line, self.col))
}
}
fn error_event(&mut self, reason: ErrorCode) -> Result<de::Token, ParserError> {
self.state.clear();
Err(SyntaxError(reason, self.line, self.col))
}
}
impl<T: Iterator<char>> de::Deserializer<ParserError> for Parser<T> {
fn end_of_stream_error(&self) -> ParserError {
SyntaxError(EOFWhileParsingValue, self.line, self.col)
}
fn syntax_error(&self) -> ParserError {
SyntaxError(InvalidSyntax, self.line, self.col)
}
// Special case treating options as a nullable value.
#[inline]
fn expect_option<
U: de::Deserializable<ParserError, Parser<T>>
>(&mut self, token: de::Token) -> Result<Option<U>, ParserError> {
match token {
de::Null => Ok(None),
token => {
let value: U = try!(de::Deserializable::deserialize_token(self, token));
Ok(Some(value))
}
}
}
// Special case treating enums as a String or a `{"variant": "...", "fields": [...]}`.
#[inline]
fn expect_enum_start(&mut self,
token: de::Token,
_name: &str,
variants: &[&str]) -> Result<uint, ParserError> {
// It's a little tricky to deserialize enums. Strings are simple to
// parse, but objects require us to preparse the entire object because
// we can't guarantee the order of the map.
let variant = match token {
de::String(variant) => {
// Make sure to terminate the enum.
self.tokens.push_front(de::End);
variant
}
de::MapStart(_len) => {
let mut variant = None;
let mut fields = None;
// Extract all the fields.
loop {
let field = match try!(self.expect_token()) {
de::End => { break; }
de::String(field) => field,
_ => { return self.error(InvalidSyntax); }
};
match field.as_slice() {
"variant" => {
let v: String = try!(de::Deserializable::deserialize(self));
variant = Some(v);
}
"fields" => {
let f: de::GatherTokens = try!(de::Deserializable::deserialize(self));
fields = Some(f.unwrap());
}
_ => { }
}
}
let (variant, fields) = match (variant, fields) {
(Some(variant), Some(fields)) => (variant, fields),
_ => { return self.error(MissingField); }
};
// Add all the field's tokens to our buffer. We need to skip
// over the `SeqStart` because we're pretending we're an
// `EnumStart`.
let mut iter = fields.move_iter();
match iter.next() {
Some(de::SeqStart(_)) => { }
_ => { return self.error(InvalidSyntax); }
}
self.tokens.extend(iter);
variant
}
_ => { return self.error(InvalidSyntax); }
};
match variants.iter().position(|v| *v == variant.as_slice()) {
Some(idx) => {
Ok(idx)
}
None => self.error(UnknownVariant),
}
}
}
/*
/// A Builder consumes a json::Parser to create a generic Json structure.
pub struct Builder<T> {
parser: Parser<T>,
token: Option<JsonEvent>,
}
impl<T: Iterator<char>> Builder<T> {
/// Create a JSON Builder.
pub fn new(src: T) -> Builder<T> {
Builder {
parser: Parser::new(src),
token: None,
}
}
// Decode a Json value from a Parser.
pub fn build(&mut self) -> Result<Json, BuilderError> {
self.bump();
let result = self.build_value();
self.bump();
match self.token {
None => {}
Some(Error(e)) => { return Err(e); }
ref tok => { fail!("unexpected token {}", tok.clone()); }
}
return result;
}
fn bump(&mut self) {
self.token = self.parser.next();
}
fn build_value(&mut self) -> Result<Json, BuilderError> {
return match self.token {
Some(NullValue) => { Ok(Null) }
Some(NumberValue(n)) => { Ok(Number(n)) }
Some(BooleanValue(b)) => { Ok(Boolean(b)) }
Some(StringValue(ref mut s)) => {
let mut temp = String::new();
swap(s, &mut temp);
Ok(String(temp))
}
Some(Error(e)) => { Err(e) }
Some(ListStart) => { self.build_list() }
Some(ObjectStart) => { self.build_object() }
Some(ObjectEnd) => { self.parser.error(InvalidSyntax) }
Some(ListEnd) => { self.parser.error(InvalidSyntax) }
None => { self.parser.error(EOFWhileParsingValue) }
}
}
fn build_list(&mut self) -> Result<Json, BuilderError> {
self.bump();
let mut values = Vec::new();
loop {
if self.token == Some(ListEnd) {
return Ok(List(values.move_iter().collect()));
}
match self.build_value() {
Ok(v) => values.push(v),
Err(e) => { return Err(e) }
}
self.bump();
}
}
fn build_object(&mut self) -> Result<Json, BuilderError> {
self.bump();
let mut values = box TreeMap::new();
while self.token != None {
match self.token {
Some(ObjectEnd) => { return Ok(Object(values)); }
Some(Error(e)) => { return Err(e); }
None => { break; }
_ => {}
}
let key = match self.parser.stack().top() {
Some(Key(k)) => { k.to_string() }
_ => { fail!("invalid state"); }
};
match self.build_value() {
Ok(value) => { values.insert(key, value); }
Err(e) => { return Err(e); }
}
self.bump();
}
return self.parser.error(EOFWhileParsingObject);
}
}
*/
/// Decodes a json value from an `Iterator<Char>`.
pub fn from_iter<
Iter: Iterator<char>,
T: de::Deserializable<ParserError, Parser<Iter>>
>(iter: Iter) -> Result<T, ParserError> {
let mut parser = Parser::new(iter);
let value = try!(de::Deserializable::deserialize(&mut parser));
// Make sure the whole stream has been consumed.
match parser.next() {
Some(Ok(_token)) => parser.error(TrailingCharacters),
Some(Err(err)) => Err(err),
None => Ok(value),
}
}
/// Decodes a json value from a `Json`.
pub fn from_json<
T: de::Deserializable<ParserError, JsonDeserializer>
>(json: Json) -> Result<T, ParserError> {
let mut d = JsonDeserializer::new(json);
de::Deserializable::deserialize(&mut d)
}
/// A structure to decode JSON to values in rust.
pub struct Decoder {
stack: Vec<Json>,
}
impl Decoder {
/// Creates a new decoder instance for decoding the specified JSON value.
pub fn new(json: Json) -> Decoder {
Decoder {
stack: vec!(json),
}
}
}
macro_rules! expect(
($e:expr, Null) => ({
match $e {
Null => Ok(()),
other => Err(ExpectedError("Null".to_string(),
format!("{}", other)))
}
});
($e:expr, $t:ident) => ({
match $e {
$t(v) => Ok(v),
other => {
Err(ExpectedError(stringify!($t).to_string(),
format!("{}", other)))
}
}
})
)
/*
impl ::Decoder<DecoderError> for Decoder {
fn read_nil(&mut self) -> DecodeResult<()> {
debug!("read_nil");
try!(expect!(self.pop(), Null));
Ok(())
}
fn read_u64(&mut self) -> DecodeResult<u64 > { Ok(try!(self.read_f64()) as u64) }
fn read_u32(&mut self) -> DecodeResult<u32 > { Ok(try!(self.read_f64()) as u32) }
fn read_u16(&mut self) -> DecodeResult<u16 > { Ok(try!(self.read_f64()) as u16) }
fn read_u8 (&mut self) -> DecodeResult<u8 > { Ok(try!(self.read_f64()) as u8) }
fn read_uint(&mut self) -> DecodeResult<uint> { Ok(try!(self.read_f64()) as uint) }
fn read_i64(&mut self) -> DecodeResult<i64> { Ok(try!(self.read_f64()) as i64) }
fn read_i32(&mut self) -> DecodeResult<i32> { Ok(try!(self.read_f64()) as i32) }
fn read_i16(&mut self) -> DecodeResult<i16> { Ok(try!(self.read_f64()) as i16) }
fn read_i8 (&mut self) -> DecodeResult<i8 > { Ok(try!(self.read_f64()) as i8) }
fn read_int(&mut self) -> DecodeResult<int> { Ok(try!(self.read_f64()) as int) }
fn read_bool(&mut self) -> DecodeResult<bool> {
debug!("read_bool");
Ok(try!(expect!(self.pop(), Boolean)))
}
fn read_f64(&mut self) -> DecodeResult<f64> {
use std::from_str::FromStr;
debug!("read_f64");
match self.pop() {
Number(f) => Ok(f),
String(s) => {
// re: #12967.. a type w/ numeric keys (ie HashMap<uint, V> etc)
// is going to have a string here, as per JSON spec..
Ok(FromStr::from_str(s.as_slice()).unwrap())
},
value => {
Err(ExpectedError("Number".to_string(),
format!("{}", value)))
}
}
}
fn read_f32(&mut self) -> DecodeResult<f32> { Ok(try!(self.read_f64()) as f32) }
fn read_char(&mut self) -> DecodeResult<char> {
let s = try!(self.read_str());
{
let mut it = s.as_slice().chars();
match (it.next(), it.next()) {
// exactly one character
(Some(c), None) => return Ok(c),
_ => ()
}
}
Err(ExpectedError("single character string".to_string(),
format!("{}", s)))
}
fn read_str(&mut self) -> DecodeResult<String> {
debug!("read_str");
Ok(try!(expect!(self.pop(), String)))
}
fn read_enum<T>(&mut self,
name: &str,
f: |&mut Decoder| -> DecodeResult<T>) -> DecodeResult<T> {
debug!("read_enum({})", name);
f(self)
}
fn read_enum_variant<T>(&mut self,
names: &[&str],
f: |&mut Decoder, uint| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_enum_variant(names={:?})", names);
let name = match self.pop() {
String(s) => s,
Object(mut o) => {
let n = match o.pop(&"variant".to_string()) {
Some(String(s)) => s,
Some(val) => {
return Err(ExpectedError("String".to_string(),
format!("{}", val)))
}
None => {
return Err(MissingFieldError("variant".to_string()))
}
};
match o.pop(&"fields".to_string()) {
Some(List(l)) => {
for field in l.move_iter().rev() {
self.stack.push(field.clone());
}
},
Some(val) => {
return Err(ExpectedError("List".to_string(),
format!("{}", val)))
}
None => {
return Err(MissingFieldError("fields".to_string()))
}
}
n
}
json => {
return Err(ExpectedError("String or Object".to_string(),
format!("{}", json)))
}
};
let idx = match names.iter()
.position(|n| {
str::eq_slice(*n, name.as_slice())
}) {
Some(idx) => idx,
None => return Err(UnknownVariantError(name))
};
f(self, idx)
}
fn read_enum_variant_arg<T>(&mut self, idx: uint, f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_enum_variant_arg(idx={})", idx);
f(self)
}
fn read_enum_struct_variant<T>(&mut self,
names: &[&str],
f: |&mut Decoder, uint| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_enum_struct_variant(names={:?})", names);
self.read_enum_variant(names, f)
}
fn read_enum_struct_variant_field<T>(&mut self,
name: &str,
idx: uint,
f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_enum_struct_variant_field(name={}, idx={})", name, idx);
self.read_enum_variant_arg(idx, f)
}
fn read_struct<T>(&mut self,
name: &str,
len: uint,
f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_struct(name={}, len={})", name, len);
let value = try!(f(self));
self.pop();
Ok(value)
}
fn read_struct_field<T>(&mut self,
name: &str,
idx: uint,
f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_struct_field(name={}, idx={})", name, idx);
let mut obj = try!(expect!(self.pop(), Object));
let value = match obj.pop(&name.to_string()) {
None => return Err(MissingFieldError(name.to_string())),
Some(json) => {
self.stack.push(json);
try!(f(self))
}
};
self.stack.push(Object(obj));
Ok(value)
}
fn read_tuple<T>(&mut self, f: |&mut Decoder, uint| -> DecodeResult<T>) -> DecodeResult<T> {
debug!("read_tuple()");
self.read_seq(f)
}
fn read_tuple_arg<T>(&mut self,
idx: uint,
f: |&mut Decoder| -> DecodeResult<T>) -> DecodeResult<T> {
debug!("read_tuple_arg(idx={})", idx);
self.read_seq_elt(idx, f)
}
fn read_tuple_struct<T>(&mut self,
name: &str,
f: |&mut Decoder, uint| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_tuple_struct(name={})", name);
self.read_tuple(f)
}
fn read_tuple_struct_arg<T>(&mut self,
idx: uint,
f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_tuple_struct_arg(idx={})", idx);
self.read_tuple_arg(idx, f)
}
fn read_option<T>(&mut self, f: |&mut Decoder, bool| -> DecodeResult<T>) -> DecodeResult<T> {
match self.pop() {
Null => f(self, false),
value => { self.stack.push(value); f(self, true) }
}
}
fn read_seq<T>(&mut self, f: |&mut Decoder, uint| -> DecodeResult<T>) -> DecodeResult<T> {
debug!("read_seq()");
let list = try!(expect!(self.pop(), List));
let len = list.len();
for v in list.move_iter().rev() {
self.stack.push(v);
}
f(self, len)
}
fn read_seq_elt<T>(&mut self,
idx: uint,
f: |&mut Decoder| -> DecodeResult<T>) -> DecodeResult<T> {
debug!("read_seq_elt(idx={})", idx);
f(self)
}
fn read_map<T>(&mut self, f: |&mut Decoder, uint| -> DecodeResult<T>) -> DecodeResult<T> {
debug!("read_map()");
let obj = try!(expect!(self.pop(), Object));
let len = obj.len();
for (key, value) in obj.move_iter() {
self.stack.push(value);
self.stack.push(String(key));
}
f(self, len)
}
fn read_map_elt_key<T>(&mut self, idx: uint, f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_map_elt_key(idx={})", idx);
f(self)
}
fn read_map_elt_val<T>(&mut self, idx: uint, f: |&mut Decoder| -> DecodeResult<T>)
-> DecodeResult<T> {
debug!("read_map_elt_val(idx={})", idx);
f(self)
}
}
*/
/// Test if two json values are less than one another
impl Ord for Json {
fn lt(&self, other: &Json) -> bool {
match *self {
Number(f0) => {
match *other {
Number(f1) => f0 < f1,
String(_) | Boolean(_) | List(_) | Object(_) |
Null => true
}
}
String(ref s0) => {
match *other {
Number(_) => false,
String(ref s1) => s0 < s1,
Boolean(_) | List(_) | Object(_) | Null => true
}
}
Boolean(b0) => {
match *other {
Number(_) | String(_) => false,
Boolean(b1) => b0 < b1,
List(_) | Object(_) | Null => true
}
}
List(ref l0) => {
match *other {
Number(_) | String(_) | Boolean(_) => false,
List(ref l1) => (*l0) < (*l1),
Object(_) | Null => true
}
}
Object(ref d0) => {
match *other {
Number(_) | String(_) | Boolean(_) | List(_) => false,
Object(ref d1) => d0 < d1,
Null => true
}
}
Null => {
match *other {
Number(_) | String(_) | Boolean(_) | List(_) |
Object(_) =>
false,
Null => true
}
}
}
}
}
/// A trait for converting values to JSON
pub trait ToJson {
/// Converts the value of `self` to an instance of JSON
fn to_json(&self) -> Json;
}
impl ToJson for Json {
fn to_json(&self) -> Json { (*self).clone() }
}
impl ToJson for int {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for i8 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for i16 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for i32 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for i64 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for uint {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for u8 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for u16 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for u32 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for u64 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for f32 {
fn to_json(&self) -> Json { Number(*self as f64) }
}
impl ToJson for f64 {
fn to_json(&self) -> Json { Number(*self) }
}
impl ToJson for () {
fn to_json(&self) -> Json { Null }
}
impl ToJson for bool {
fn to_json(&self) -> Json { Boolean(*self) }
}
impl<'a> ToJson for &'a str {
fn to_json(&self) -> Json { String(self.to_string()) }
}
impl ToJson for String {
fn to_json(&self) -> Json { String((*self).clone()) }
}
impl<A:ToJson,B:ToJson> ToJson for (A, B) {
fn to_json(&self) -> Json {
match *self {
(ref a, ref b) => {
List(vec![a.to_json(), b.to_json()])
}
}
}
}
impl<A:ToJson,B:ToJson,C:ToJson> ToJson for (A, B, C) {
fn to_json(&self) -> Json {
match *self {
(ref a, ref b, ref c) => {
List(vec![a.to_json(), b.to_json(), c.to_json()])
}
}
}
}
impl<A:ToJson> ToJson for ~[A] {
fn to_json(&self) -> Json { List(self.iter().map(|elt| elt.to_json()).collect()) }
}
impl<A:ToJson> ToJson for Vec<A> {
fn to_json(&self) -> Json { List(self.iter().map(|elt| elt.to_json()).collect()) }
}
impl<A:ToJson> ToJson for TreeMap<String, A> {
fn to_json(&self) -> Json {
let mut d = TreeMap::new();
for (key, value) in self.iter() {
d.insert((*key).clone(), value.to_json());
}
Object(d)
}
}
impl<A:ToJson> ToJson for HashMap<String, A> {
fn to_json(&self) -> Json {
let mut d = TreeMap::new();
for (key, value) in self.iter() {
d.insert((*key).clone(), value.to_json());
}
Object(d)
}
}
impl<A:ToJson> ToJson for Option<A> {
fn to_json(&self) -> Json {
match *self {
None => Null,
Some(ref value) => value.to_json()
}
}
}
/*
impl fmt::Show for Json {
/// Encodes a json value into a string
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.to_writer(f).map_err(|_| fmt::WriteError)
}
}
*/
#[cfg(test)]
mod tests {
extern crate test;
use self::test::Bencher;
use super::{Json, String, List, Object};
use super::{Parser, ParserError, from_iter};
use super::{JsonDeserializer, from_json, ToJson};
use super::{
EOFWhileParsingList,
EOFWhileParsingObject,
EOFWhileParsingString,
EOFWhileParsingValue,
ExpectedColon,
InvalidNumber,
InvalidSyntax,
KeyMustBeAString,
TrailingCharacters,
SyntaxError,
};
use de;
use std::fmt::Show;
use std::str;
use collections::TreeMap;
macro_rules! treemap {
($($k:expr => $v:expr),*) => ({
let mut _m = ::collections::TreeMap::new();
$(_m.insert($k, $v);)*
_m
})
}
#[deriving(Eq, Show)]
enum Animal {
Dog,
Frog(String, int)
}
impl<E, D: de::Deserializer<E>> de::Deserializable<E, D> for Animal {
#[inline]
fn deserialize_token(d: &mut D, token: de::Token) -> Result<Animal, E> {
match try!(d.expect_enum_start(token, "Animal", ["Dog", "Frog"])) {
0 => {
try!(d.expect_end());
Ok(Dog)
}
1 => {
let x0 = try!(de::Deserializable::deserialize(d));
let x1 = try!(de::Deserializable::deserialize(d));
try!(d.expect_end());
Ok(Frog(x0, x1))
}
_ => Err(d.syntax_error()),
}
}
}
impl ToJson for Animal {
fn to_json(&self) -> Json {
match *self {
Dog => String("Dog".to_string()),
Frog(ref x0, x1) => {
Object(
treemap!(
"variant".to_string() => "Frog".to_json(),
"fields".to_string() => List(vec!(x0.to_json(), x1.to_json()))
)
)
}
}
}
}
#[deriving(Eq, Show)]
struct Inner {
a: (),
b: uint,
c: Vec<String>,
}
impl<E, D: de::Deserializer<E>> de::Deserializable<E, D> for Inner {
#[inline]
fn deserialize_token(d: &mut D, token: de::Token) -> Result<Inner, E> {
match token {
de::StructStart("Inner", _) |
de::MapStart(_) => {
let mut a = None;
let mut b = None;
let mut c = None;
loop {
match try!(d.expect_token()) {
de::End => { break; }
de::Str(name) => {
match name {
"a" => {
a = Some(try!(de::Deserializable::deserialize(d)));
}
"b" => {
b = Some(try!(de::Deserializable::deserialize(d)));
}
"c" => {
c = Some(try!(de::Deserializable::deserialize(d)));
}
_ => { }
}
}
de::String(ref name) => {
match name.as_slice() {
"a" => {
a = Some(try!(de::Deserializable::deserialize(d)));
}
"b" => {
b = Some(try!(de::Deserializable::deserialize(d)));
}
"c" => {
c = Some(try!(de::Deserializable::deserialize(d)));
}
_ => { }
}
}
_ => { return Err(d.syntax_error()); }
}
}
match (a, b, c) {
(Some(a), Some(b), Some(c)) => {
Ok(Inner { a: a, b: b, c: c })
}
_ => Err(d.syntax_error()),
}
}
_ => Err(d.syntax_error()),
}
}
}
impl ToJson for Inner {
fn to_json(&self) -> Json {
Object(
treemap!(
"a".to_string() => self.a.to_json(),
"b".to_string() => self.b.to_json(),
"c".to_string() => self.c.to_json()
)
)
}
}
#[deriving(Eq, Show)]
struct Outer {
inner: Vec<Inner>,
}
impl<E, D: de::Deserializer<E>> de::Deserializable<E, D> for Outer {
#[inline]
fn deserialize_token(d: &mut D, token: de::Token) -> Result<Outer, E> {
match token {
de::StructStart("Outer", _) |
de::MapStart(_) => {
let mut inner = None;
loop {
match try!(d.expect_token()) {
de::End => { break; }
de::Str(name) => {
match name {
"inner" => {
inner = Some(try!(de::Deserializable::deserialize(d)));
}
_ => { }
}
}
de::String(ref name) => {
match name.as_slice() {
"inner" => {
inner = Some(try!(de::Deserializable::deserialize(d)));
}
_ => { }
}
}
_ => { return Err(d.syntax_error()); }
}
}
match inner {
Some(inner) => {
Ok(Outer { inner: inner })
}
_ => Err(d.syntax_error()),
}
}
_ => Err(d.syntax_error()),
}
}
}
impl ToJson for Outer {
fn to_json(&self) -> Json {
Object(
treemap!(
"inner".to_string() => self.inner.to_json()
)
)
}
}
/*
fn mk_object(items: &[(String, Json)]) -> Json {
let mut d = box TreeMap::new();
for item in items.iter() {
match *item {
(ref key, ref value) => { d.insert((*key).clone(), (*value).clone()); },
}
};
Object(d)
}
#[test]
fn test_write_null() {
assert_eq!(Null.to_str().into_string(), "null".to_string());
assert_eq!(Null.to_pretty_str().into_string(), "null".to_string());
}
#[test]
fn test_write_number() {
assert_eq!(Number(3.0).to_str().into_string(), "3".to_string());
assert_eq!(Number(3.0).to_pretty_str().into_string(), "3".to_string());
assert_eq!(Number(3.1).to_str().into_string(), "3.1".to_string());
assert_eq!(Number(3.1).to_pretty_str().into_string(), "3.1".to_string());
assert_eq!(Number(-1.5).to_str().into_string(), "-1.5".to_string());
assert_eq!(Number(-1.5).to_pretty_str().into_string(), "-1.5".to_string());
assert_eq!(Number(0.5).to_str().into_string(), "0.5".to_string());
assert_eq!(Number(0.5).to_pretty_str().into_string(), "0.5".to_string());
}
#[test]
fn test_write_str() {
assert_eq!(String("".to_string()).to_str().into_string(), "\"\"".to_string());
assert_eq!(String("".to_string()).to_pretty_str().into_string(), "\"\"".to_string());
assert_eq!(String("foo".to_string()).to_str().into_string(), "\"foo\"".to_string());
assert_eq!(String("foo".to_string()).to_pretty_str().into_string(), "\"foo\"".to_string());
}
#[test]
fn test_write_bool() {
assert_eq!(Boolean(true).to_str().into_string(), "true".to_string());
assert_eq!(Boolean(true).to_pretty_str().into_string(), "true".to_string());
assert_eq!(Boolean(false).to_str().into_string(), "false".to_string());
assert_eq!(Boolean(false).to_pretty_str().into_string(), "false".to_string());
}
#[test]
fn test_write_list() {
assert_eq!(List(vec![]).to_str().into_string(), "[]".to_string());
assert_eq!(List(vec![]).to_pretty_str().into_string(), "[]".to_string());
assert_eq!(List(vec![Boolean(true)]).to_str().into_string(), "[true]".to_string());
assert_eq!(
List(vec![Boolean(true)]).to_pretty_str().into_string(),
"\
[\n \
true\n\
]".to_string()
);
let long_test_list = List(vec![
Boolean(false),
Null,
List(vec![String("foo\nbar".to_string()), Number(3.5)])]);
assert_eq!(long_test_list.to_str().into_string(),
"[false,null,[\"foo\\nbar\",3.5]]".to_string());
assert_eq!(
long_test_list.to_pretty_str().into_string(),
"\
[\n \
false,\n \
null,\n \
[\n \
\"foo\\nbar\",\n \
3.5\n \
]\n\
]".to_string()
);
}
#[test]
fn test_write_object() {
assert_eq!(mk_object([]).to_str().into_string(), "{}".to_string());
assert_eq!(mk_object([]).to_pretty_str().into_string(), "{}".to_string());
assert_eq!(
mk_object([
("a".to_string(), Boolean(true))
]).to_str().into_string(),
"{\"a\":true}".to_string()
);
assert_eq!(
mk_object([("a".to_string(), Boolean(true))]).to_pretty_str(),
"\
{\n \
\"a\": true\n\
}".to_string()
);
let complex_obj = mk_object([
("b".to_string(), List(vec![
mk_object([("c".to_string(), String("\x0c\r".to_string()))]),
mk_object([("d".to_string(), String("".to_string()))])
]))
]);
assert_eq!(
complex_obj.to_str().into_string(),
"{\
\"b\":[\
{\"c\":\"\\f\\r\"},\
{\"d\":\"\"}\
]\
}".to_string()
);
assert_eq!(
complex_obj.to_pretty_str().into_string(),
"\
{\n \
\"b\": [\n \
{\n \
\"c\": \"\\f\\r\"\n \
},\n \
{\n \
\"d\": \"\"\n \
}\n \
]\n\
}".to_string()
);
let a = mk_object([
("a".to_string(), Boolean(true)),
("b".to_string(), List(vec![
mk_object([("c".to_string(), String("\x0c\r".to_string()))]),
mk_object([("d".to_string(), String("".to_string()))])
]))
]);
// We can't compare the strings directly because the object fields be
// printed in a different order.
assert_eq!(a.clone(), from_str(a.to_str().as_slice()).unwrap());
assert_eq!(a.clone(),
from_str(a.to_pretty_str().as_slice()).unwrap());
}
fn with_str_writer(f: |&mut io::Writer|) -> String {
use std::io::MemWriter;
use std::str;
let mut m = MemWriter::new();
f(&mut m as &mut io::Writer);
str::from_utf8(m.unwrap().as_slice()).unwrap().to_string()
}
#[test]
fn test_write_enum() {
let animal = Dog;
assert_eq!(
with_str_writer(|wr| {
let mut encoder = Encoder::new(wr);
animal.encode(&mut encoder).unwrap();
}),
"\"Dog\"".to_string()
);
assert_eq!(
with_str_writer(|wr| {
let mut encoder = PrettyEncoder::new(wr);
animal.encode(&mut encoder).unwrap();
}),
"\"Dog\"".to_string()
);
let animal = Frog("Henry".to_string(), 349);
assert_eq!(
with_str_writer(|wr| {
let mut encoder = Encoder::new(wr);
animal.encode(&mut encoder).unwrap();
}),
"{\"variant\":\"Frog\",\"fields\":[\"Henry\",349]}".to_string()
);
assert_eq!(
with_str_writer(|wr| {
let mut encoder = PrettyEncoder::new(wr);
animal.encode(&mut encoder).unwrap();
}),
"\
[\n \
\"Frog\",\n \
\"Henry\",\n \
349\n\
]".to_string()
);
}
#[test]
fn test_write_some() {
let value = Some("jodhpurs".to_string());
let s = with_str_writer(|wr| {
let mut encoder = Encoder::new(wr);
value.encode(&mut encoder).unwrap();
});
assert_eq!(s, "\"jodhpurs\"".to_string());
let value = Some("jodhpurs".to_string());
let s = with_str_writer(|wr| {
let mut encoder = PrettyEncoder::new(wr);
value.encode(&mut encoder).unwrap();
});
assert_eq!(s, "\"jodhpurs\"".to_string());
}
#[test]
fn test_write_none() {
let value: Option<String> = None;
let s = with_str_writer(|wr| {
let mut encoder = Encoder::new(wr);
value.encode(&mut encoder).unwrap();
});
assert_eq!(s, "null".to_string());
let s = with_str_writer(|wr| {
let mut encoder = Encoder::new(wr);
value.encode(&mut encoder).unwrap();
});
assert_eq!(s, "null".to_string());
}
#[test]
fn test_read_identifiers() {
("n", SyntaxError(InvalidSyntax, 1, 2)),
("nul", SyntaxError(InvalidSyntax, 1, 4)),
("t", SyntaxError(InvalidSyntax, 1, 2)),
("truz", SyntaxError(InvalidSyntax, 1, 4)),
("f", SyntaxError(InvalidSyntax, 1, 2)),
("faz", SyntaxError(InvalidSyntax, 1, 3)),
assert_eq!(from_str("null"), Ok(Null));
assert_eq!(from_str("true"), Ok(Boolean(true)));
assert_eq!(from_str("false"), Ok(Boolean(false)));
assert_eq!(from_str(" null "), Ok(Null));
assert_eq!(from_str(" true "), Ok(Boolean(true)));
assert_eq!(from_str(" false "), Ok(Boolean(false)));
}
*/
// FIXME (#5527): these could be merged once UFCS is finished.
fn test_parse_err<
'a,
T: Eq + Show + de::Deserializable<ParserError, Parser<str::Chars<'a>>>
>(errors: &[(&'a str, ParserError)]) {
for &(s, ref err) in errors.iter() {
let v: Result<T, ParserError> = from_iter(s.chars());
assert_eq!(v.unwrap_err(), *err);
}
}
fn test_parse_ok<
'a,
T: Eq + Show + ToJson + de::Deserializable<ParserError, Parser<str::Chars<'a>>>
>(errors: &[(&'a str, T)]) {
for &(s, ref value) in errors.iter() {
let v: T = from_iter(s.chars()).unwrap();
assert_eq!(v, *value);
let v: Json = from_iter(s.chars()).unwrap();
assert_eq!(v, value.to_json());
}
}
fn test_json_deserialize_ok<
T: Eq + Show + ToJson + de::Deserializable<ParserError, JsonDeserializer>
>(errors: &[T]) {
for value in errors.iter() {
let v: T = from_json(value.to_json()).unwrap();
assert_eq!(v, *value);
// Make sure we can round trip back to `Json`.
let v: Json = from_json(value.to_json()).unwrap();
assert_eq!(v, value.to_json());
}
}
#[test]
fn test_parse_null() {
test_parse_err::<()>([
("n", SyntaxError(InvalidSyntax, 1, 2)),
("nul", SyntaxError(InvalidSyntax, 1, 4)),
("nulla", SyntaxError(TrailingCharacters, 1, 5)),
]);
test_parse_ok([
("null", ()),
]);
}
#[test]
fn test_json_deserialize_null() {
test_json_deserialize_ok([
(),
]);
}
#[test]
fn test_parse_bool() {
test_parse_err::<bool>([
("t", SyntaxError(InvalidSyntax, 1, 2)),
("truz", SyntaxError(InvalidSyntax, 1, 4)),
("f", SyntaxError(InvalidSyntax, 1, 2)),
("faz", SyntaxError(InvalidSyntax, 1, 3)),
("truea", SyntaxError(TrailingCharacters, 1, 5)),
("falsea", SyntaxError(TrailingCharacters, 1, 6)),
]);
test_parse_ok([
("true", true),
("false", false),
]);
}
#[test]
fn test_json_deserialize_bool() {
test_json_deserialize_ok([
true,
false,
]);
}
/*
#[test]
fn test_read_number() {
assert_eq!(from_str("+"), Err(SyntaxError(InvalidSyntax, 1, 1)));
assert_eq!(from_str("."), Err(SyntaxError(InvalidSyntax, 1, 1)));
assert_eq!(from_str("-"), Err(SyntaxError(InvalidNumber, 1, 2)));
assert_eq!(from_str("00"), Err(SyntaxError(InvalidNumber, 1, 2)));
assert_eq!(from_str("1."), Err(SyntaxError(InvalidNumber, 1, 3)));
assert_eq!(from_str("1e"), Err(SyntaxError(InvalidNumber, 1, 3)));
assert_eq!(from_str("1e+"), Err(SyntaxError(InvalidNumber, 1, 4)));
assert_eq!(from_str("3"), Ok(Number(3.0)));
assert_eq!(from_str("3.1"), Ok(Number(3.1)));
assert_eq!(from_str("-1.2"), Ok(Number(-1.2)));
assert_eq!(from_str("0.4"), Ok(Number(0.4)));
assert_eq!(from_str("0.4e5"), Ok(Number(0.4e5)));
assert_eq!(from_str("0.4e+15"), Ok(Number(0.4e15)));
assert_eq!(from_str("0.4e-01"), Ok(Number(0.4e-01)));
assert_eq!(from_str(" 3 "), Ok(Number(3.0)));
}
*/
#[test]
fn test_parse_numbers() {
test_parse_err::<f64>([
("+", SyntaxError(InvalidSyntax, 1, 1)),
(".", SyntaxError(InvalidSyntax, 1, 1)),
("-", SyntaxError(InvalidNumber, 1, 2)),
("00", SyntaxError(InvalidNumber, 1, 2)),
("1.", SyntaxError(InvalidNumber, 1, 3)),
("1e", SyntaxError(InvalidNumber, 1, 3)),
("1e+", SyntaxError(InvalidNumber, 1, 4)),
("1a", SyntaxError(TrailingCharacters, 1, 2)),
]);
test_parse_ok([
("3", 3.0),
("3.1", 3.1),
("-1.2", -1.2),
("0.4", 0.4),
("0.4e5", 0.4e5),
("0.4e15", 0.4e15),
("0.4e-01", 0.4e-01),
]);
}
#[test]
fn test_json_deserialize_numbers() {
test_json_deserialize_ok([
3.0,
3.1,
-1.2,
0.4,
0.4e5,
0.4e15,
0.4e-01,
]);
}
/*
#[test]
fn test_read_str() {
assert_eq!(from_str("\""), Err(SyntaxError(EOFWhileParsingString, 1, 2)));
assert_eq!(from_str("\"lol"), Err(SyntaxError(EOFWhileParsingString, 1, 5)));
assert_eq!(from_str("\"\""), Ok(String("".to_string())));
assert_eq!(from_str("\"foo\""), Ok(String("foo".to_string())));
assert_eq!(from_str("\"\\\"\""), Ok(String("\"".to_string())));
assert_eq!(from_str("\"\\b\""), Ok(String("\x08".to_string())));
assert_eq!(from_str("\"\\n\""), Ok(String("\n".to_string())));
assert_eq!(from_str("\"\\r\""), Ok(String("\r".to_string())));
assert_eq!(from_str("\"\\t\""), Ok(String("\t".to_string())));
assert_eq!(from_str(" \"foo\" "), Ok(String("foo".to_string())));
assert_eq!(from_str("\"\\u12ab\""), Ok(String("\u12ab".to_string())));
assert_eq!(from_str("\"\\uAB12\""), Ok(String("\uAB12".to_string())));
}
*/
#[test]
fn test_parse_str() {
test_parse_err::<String>([
("\"", SyntaxError(EOFWhileParsingString, 1, 2)),
("\"lol", SyntaxError(EOFWhileParsingString, 1, 5)),
("\"lol\"a", SyntaxError(TrailingCharacters, 1, 6)),
]);
test_parse_ok([
("\"\"", "".to_string()),
("\"foo\"", "foo".to_string()),
("\"\\\"\"", "\"".to_string()),
("\"\\b\"", "\x08".to_string()),
("\"\\n\"", "\n".to_string()),
("\"\\r\"", "\r".to_string()),
("\"\\t\"", "\t".to_string()),
("\"\\u12ab\"", "\u12ab".to_string()),
("\"\\uAB12\"", "\uAB12".to_string()),
]);
}
#[test]
fn test_json_deserialize_str() {
test_json_deserialize_ok([
"".to_string(),
"foo".to_string(),
"\"".to_string(),
"\x08".to_string(),
"\n".to_string(),
"\r".to_string(),
"\t".to_string(),
"\u12ab".to_string(),
"\uAB12".to_string(),
]);
}
/*
#[test]
fn test_read_list() {
assert_eq!(from_str("["), Err(SyntaxError(EOFWhileParsingValue, 1, 2)));
assert_eq!(from_str("[1"), Err(SyntaxError(EOFWhileParsingList, 1, 3)));
assert_eq!(from_str("[1,"), Err(SyntaxError(EOFWhileParsingValue, 1, 4)));
assert_eq!(from_str("[1,]"), Err(SyntaxError(InvalidSyntax, 1, 4)));
assert_eq!(from_str("[6 7]"), Err(SyntaxError(InvalidSyntax, 1, 4)));
assert_eq!(from_str("[]"), Ok(List(vec![])));
assert_eq!(from_str("[ ]"), Ok(List(vec![])));
assert_eq!(from_str("[true]"), Ok(List(vec![Boolean(true)])));
assert_eq!(from_str("[ false ]"), Ok(List(vec![Boolean(false)])));
assert_eq!(from_str("[null]"), Ok(List(vec![Null])));
assert_eq!(from_str("[3, 1]"),
Ok(List(vec![Number(3.0), Number(1.0)])));
assert_eq!(from_str("\n[3, 2]\n"),
Ok(List(vec![Number(3.0), Number(2.0)])));
assert_eq!(from_str("[2, [4, 1]]"),
Ok(List(vec![Number(2.0), List(vec![Number(4.0), Number(1.0)])])));
}
*/
#[test]
fn test_parse_list() {
test_parse_err::<Vec<f64>>([
("[", SyntaxError(EOFWhileParsingValue, 1, 2)),
("[ ", SyntaxError(EOFWhileParsingValue, 1, 3)),
("[1", SyntaxError(EOFWhileParsingList, 1, 3)),
("[1,", SyntaxError(EOFWhileParsingValue, 1, 4)),
("[1,]", SyntaxError(InvalidSyntax, 1, 4)),
("[1 2]", SyntaxError(InvalidSyntax, 1, 4)),
("[]a", SyntaxError(TrailingCharacters, 1, 3)),
]);
test_parse_ok([
("[]", vec!()),
("[ ]", vec!()),
("[null]", vec!(())),
("[ null ]", vec!(())),
]);
test_parse_ok([
("[true]", vec!(true)),
]);
test_parse_ok([
("[3,1]", vec!(3, 1)),
("[ 3 , 1 ]", vec!(3, 1)),
]);
test_parse_ok([
("[[3], [1, 2]]", vec!(vec!(3), vec!(1, 2))),
]);
}
#[test]
fn test_json_deserialize_list() {
test_json_deserialize_ok([
vec!(),
vec!(()),
]);
test_json_deserialize_ok([
vec!(true),
]);
test_json_deserialize_ok([
vec!(3, 1),
]);
test_json_deserialize_ok([
vec!(vec!(3), vec!(1, 2)),
]);
}
/*
#[test]
fn test_read_object() {
assert_eq!(from_str("{"), Err(SyntaxError(EOFWhileParsingObject, 1, 2)));
assert_eq!(from_str("{ "), Err(SyntaxError(EOFWhileParsingObject, 1, 3)));
assert_eq!(from_str("{1"), Err(SyntaxError(KeyMustBeAString, 1, 2)));
assert_eq!(from_str("{ \"a\""), Err(SyntaxError(EOFWhileParsingObject, 1, 6)));
assert_eq!(from_str("{\"a\""), Err(SyntaxError(EOFWhileParsingObject, 1, 5)));
assert_eq!(from_str("{\"a\" "), Err(SyntaxError(EOFWhileParsingObject, 1, 6)));
assert_eq!(from_str("{\"a\" 1"), Err(SyntaxError(ExpectedColon, 1, 6)));
assert_eq!(from_str("{\"a\":"), Err(SyntaxError(EOFWhileParsingValue, 1, 6)));
assert_eq!(from_str("{\"a\":1"), Err(SyntaxError(EOFWhileParsingObject, 1, 7)));
assert_eq!(from_str("{\"a\":1 1"), Err(SyntaxError(InvalidSyntax, 1, 8)));
assert_eq!(from_str("{\"a\":1,"), Err(SyntaxError(EOFWhileParsingObject, 1, 8)));
assert_eq!(from_str("{}").unwrap(), mk_object([]));
assert_eq!(from_str("{\"a\": 3}").unwrap(),
mk_object([("a".to_string(), Number(3.0))]));
assert_eq!(from_str(
"{ \"a\": null, \"b\" : true }").unwrap(),
mk_object([
("a".to_string(), Null),
("b".to_string(), Boolean(true))]));
assert_eq!(from_str("\n{ \"a\": null, \"b\" : true }\n").unwrap(),
mk_object([
("a".to_string(), Null),
("b".to_string(), Boolean(true))]));
assert_eq!(from_str(
"{\"a\" : 1.0 ,\"b\": [ true ]}").unwrap(),
mk_object([
("a".to_string(), Number(1.0)),
("b".to_string(), List(vec![Boolean(true)]))
]));
assert_eq!(from_str(
"{\
\"a\": 1.0, \
\"b\": [\
true,\
\"foo\\nbar\", \
{ \"c\": {\"d\": null} } \
]\
}").unwrap(),
mk_object([
("a".to_string(), Number(1.0)),
("b".to_string(), List(vec![
Boolean(true),
String("foo\nbar".to_string()),
mk_object([
("c".to_string(), mk_object([("d".to_string(), Null)]))
])
]))
]));
}
*/
#[test]
fn test_parse_object() {
test_parse_err::<TreeMap<String, int>>([
("{", SyntaxError(EOFWhileParsingString, 1, 2)),
("{ ", SyntaxError(EOFWhileParsingString, 1, 3)),
("{1", SyntaxError(KeyMustBeAString, 1, 2)),
("{ \"a\"", SyntaxError(EOFWhileParsingObject, 1, 6)),
("{\"a\"", SyntaxError(EOFWhileParsingObject, 1, 5)),
("{\"a\" ", SyntaxError(EOFWhileParsingObject, 1, 6)),
("{\"a\" 1", SyntaxError(ExpectedColon, 1, 6)),
("{\"a\":", SyntaxError(EOFWhileParsingValue, 1, 6)),
("{\"a\":1", SyntaxError(EOFWhileParsingObject, 1, 7)),
("{\"a\":1 1", SyntaxError(InvalidSyntax, 1, 8)),
("{\"a\":1,", SyntaxError(EOFWhileParsingString, 1, 8)),
("{}a", SyntaxError(TrailingCharacters, 1, 3)),
]);
test_parse_ok([
("{}", treemap!()),
("{ }", treemap!()),
(
"{\"a\":3}",
treemap!("a".to_string() => 3)
),
(
"{ \"a\" : 3 }",
treemap!("a".to_string() => 3)
),
(
"{\"a\":3,\"b\":4}",
treemap!("a".to_string() => 3, "b".to_string() => 4)
),
(
"{ \"a\" : 3 , \"b\" : 4 }",
treemap!("a".to_string() => 3, "b".to_string() => 4),
),
]);
test_parse_ok([
(
"{\"a\": {\"b\": 3, \"c\": 4}}",
treemap!("a".to_string() => treemap!("b".to_string() => 3, "c".to_string() => 4)),
),
]);
}
#[test]
fn test_json_deserialize_object() {
test_json_deserialize_ok([
treemap!(),
treemap!("a".to_string() => 3),
treemap!("a".to_string() => 3, "b".to_string() => 4),
]);
test_json_deserialize_ok([
treemap!("a".to_string() => treemap!("b".to_string() => 3, "c".to_string() => 4)),
]);
}
#[test]
fn test_parse_struct() {
test_parse_ok([
(
"{
\"inner\": []
}",
Outer {
inner: vec![]
},
),
(
"{
\"inner\": [
{ \"a\": null, \"b\": 2, \"c\": [\"abc\", \"xyz\"] }
]
}",
Outer {
inner: vec![
Inner { a: (), b: 2, c: vec!["abc".to_string(), "xyz".to_string()] }
]
},
)
]);
}
#[test]
fn test_json_deserialize_struct() {
test_json_deserialize_ok([
Outer {
inner: vec![
Inner { a: (), b: 2, c: vec!["abc".to_string(), "xyz".to_string()] }
]
},
]);
}
#[test]
fn test_parse_option() {
test_parse_ok([
("null", None),
("\"jodhpurs\"", Some("jodhpurs".to_string())),
]);
}
#[test]
fn test_json_deserialize_option() {
test_json_deserialize_ok([
None,
Some("jodhpurs".to_string()),
]);
}
#[test]
fn test_parse_enum() {
test_parse_ok([
("\"Dog\"", Dog),
(
"{\"variant\": \"Frog\", \"fields\": [\"Henry\", 349]}",
Frog("Henry".to_string(), 349),
)
]);
}
#[test]
fn test_json_deserialize_enum() {
test_json_deserialize_ok([
Dog,
Frog("Henry".to_string(), 349),
]);
}
/*
#[test]
fn test_decode_map() {
let s = "{\"a\": \"Dog\", \"b\": {\"variant\":\"Frog\",\
\"fields\":[\"Henry\", 349]}}";
let mut decoder = Decoder::new(from_str(s).unwrap());
let mut map: TreeMap<String, Animal> = Decodable::decode(&mut decoder).unwrap();
assert_eq!(map.pop(&"a".to_string()), Some(Dog));
assert_eq!(map.pop(&"b".to_string()), Some(Frog("Henry".to_string(), 349)));
}
#[test]
fn test_multiline_errors() {
assert_eq!(from_str("{\n \"foo\":\n \"bar\""),
Err(SyntaxError(EOFWhileParsingObject, 3u, 8u)));
}
#[deriving(Decodable)]
struct DecodeStruct {
x: f64,
y: bool,
z: String,
w: Vec<DecodeStruct>
}
#[deriving(Decodable)]
enum DecodeEnum {
A(f64),
B(String)
}
fn check_err<T: Decodable<Decoder, DecoderError>>(to_parse: &'static str,
expected: DecoderError) {
let res: DecodeResult<T> = match from_str(to_parse) {
Err(e) => Err(ParseError(e)),
Ok(json) => Decodable::decode(&mut Decoder::new(json))
};
match res {
Ok(_) => fail!("`{}` parsed & decoded ok, expecting error `{}`",
to_parse, expected),
Err(ParseError(e)) => fail!("`{}` is not valid json: {}",
to_parse, e),
Err(e) => {
assert_eq!(e, expected);
}
}
}
#[test]
fn test_decode_errors_struct() {
check_err::<DecodeStruct>("[]", ExpectedError("Object".to_string(), "[]".to_string()));
check_err::<DecodeStruct>("{\"x\": true, \"y\": true, \"z\": \"\", \"w\": []}",
ExpectedError("Number".to_string(), "true".to_string()));
check_err::<DecodeStruct>("{\"x\": 1, \"y\": [], \"z\": \"\", \"w\": []}",
ExpectedError("Boolean".to_string(), "[]".to_string()));
check_err::<DecodeStruct>("{\"x\": 1, \"y\": true, \"z\": {}, \"w\": []}",
ExpectedError("String".to_string(), "{}".to_string()));
check_err::<DecodeStruct>("{\"x\": 1, \"y\": true, \"z\": \"\", \"w\": null}",
ExpectedError("List".to_string(), "null".to_string()));
check_err::<DecodeStruct>("{\"x\": 1, \"y\": true, \"z\": \"\"}",
MissingFieldError("w".to_string()));
}
#[test]
fn test_decode_errors_enum() {
check_err::<DecodeEnum>("{}",
MissingFieldError("variant".to_string()));
check_err::<DecodeEnum>("{\"variant\": 1}",
ExpectedError("String".to_string(), "1".to_string()));
check_err::<DecodeEnum>("{\"variant\": \"A\"}",
MissingFieldError("fields".to_string()));
check_err::<DecodeEnum>("{\"variant\": \"A\", \"fields\": null}",
ExpectedError("List".to_string(), "null".to_string()));
check_err::<DecodeEnum>("{\"variant\": \"C\", \"fields\": []}",
UnknownVariantError("C".to_string()));
}
#[test]
fn test_find(){
let json_value = from_str("{\"dog\" : \"cat\"}").unwrap();
let found_str = json_value.find(&"dog".to_string());
assert!(found_str.is_some() && found_str.unwrap().as_string().unwrap() == "cat");
}
#[test]
fn test_find_path(){
let json_value = from_str("{\"dog\":{\"cat\": {\"mouse\" : \"cheese\"}}}").unwrap();
let found_str = json_value.find_path(&[&"dog".to_string(),
&"cat".to_string(), &"mouse".to_string()]);
assert!(found_str.is_some() && found_str.unwrap().as_string().unwrap() == "cheese");
}
#[test]
fn test_search(){
let json_value = from_str("{\"dog\":{\"cat\": {\"mouse\" : \"cheese\"}}}").unwrap();
let found_str = json_value.search(&"mouse".to_string()).and_then(|j| j.as_string());
assert!(found_str.is_some());
assert!(found_str.unwrap() == "cheese");
}
#[test]
fn test_is_object(){
let json_value = from_str("{}").unwrap();
assert!(json_value.is_object());
}
#[test]
fn test_as_object(){
let json_value = from_str("{}").unwrap();
let json_object = json_value.as_object();
assert!(json_object.is_some());
}
#[test]
fn test_is_list(){
let json_value = from_str("[1, 2, 3]").unwrap();
assert!(json_value.is_list());
}
#[test]
fn test_as_list(){
let json_value = from_str("[1, 2, 3]").unwrap();
let json_list = json_value.as_list();
let expected_length = 3;
assert!(json_list.is_some() && json_list.unwrap().len() == expected_length);
}
#[test]
fn test_is_string(){
let json_value = from_str("\"dog\"").unwrap();
assert!(json_value.is_string());
}
#[test]
fn test_as_string(){
let json_value = from_str("\"dog\"").unwrap();
let json_str = json_value.as_string();
let expected_str = "dog";
assert_eq!(json_str, Some(expected_str));
}
#[test]
fn test_is_number(){
let json_value = from_str("12").unwrap();
assert!(json_value.is_number());
}
#[test]
fn test_as_number(){
let json_value = from_str("12").unwrap();
let json_num = json_value.as_number();
let expected_num = 12f64;
assert!(json_num.is_some() && json_num.unwrap() == expected_num);
}
#[test]
fn test_is_boolean(){
let json_value = from_str("false").unwrap();
assert!(json_value.is_boolean());
}
#[test]
fn test_as_boolean(){
let json_value = from_str("false").unwrap();
let json_bool = json_value.as_boolean();
let expected_bool = false;
assert!(json_bool.is_some() && json_bool.unwrap() == expected_bool);
}
#[test]
fn test_is_null(){
let json_value = from_str("null").unwrap();
assert!(json_value.is_null());
}
#[test]
fn test_as_null(){
let json_value = from_str("null").unwrap();
let json_null = json_value.as_null();
let expected_null = ();
assert!(json_null.is_some() && json_null.unwrap() == expected_null);
}
#[test]
fn test_encode_hashmap_with_numeric_key() {
use std::str::from_utf8;
use std::io::Writer;
use std::io::MemWriter;
use collections::HashMap;
let mut hm: HashMap<uint, bool> = HashMap::new();
hm.insert(1, true);
let mut mem_buf = MemWriter::new();
{
let mut encoder = Encoder::new(&mut mem_buf as &mut io::Writer);
hm.encode(&mut encoder).unwrap();
}
let bytes = mem_buf.unwrap();
let json_str = from_utf8(bytes.as_slice()).unwrap();
match from_str(json_str) {
Err(_) => fail!("Unable to parse json_str: {:?}", json_str),
_ => {} // it parsed and we are good to go
}
}
#[test]
fn test_prettyencode_hashmap_with_numeric_key() {
use std::str::from_utf8;
use std::io::Writer;
use std::io::MemWriter;
use collections::HashMap;
let mut hm: HashMap<uint, bool> = HashMap::new();
hm.insert(1, true);
let mut mem_buf = MemWriter::new();
{
let mut encoder = PrettyEncoder::new(&mut mem_buf as &mut io::Writer);
hm.encode(&mut encoder).unwrap()
}
let bytes = mem_buf.unwrap();
let json_str = from_utf8(bytes.as_slice()).unwrap();
match from_str(json_str) {
Err(_) => fail!("Unable to parse json_str: {:?}", json_str),
_ => {} // it parsed and we are good to go
}
}
#[test]
fn test_hashmap_with_numeric_key_can_handle_double_quote_delimited_key() {
use collections::HashMap;
use Decodable;
let json_str = "{\"1\":true}";
let json_obj = match from_str(json_str) {
Err(_) => fail!("Unable to parse json_str: {:?}", json_str),
Ok(o) => o
};
let mut decoder = Decoder::new(json_obj);
let _hm: HashMap<uint, bool> = Decodable::decode(&mut decoder).unwrap();
}
fn assert_stream_equal(src: &str, expected: ~[(JsonEvent, ~[StackElement])]) {
let mut parser = Parser::new(src.chars());
let mut i = 0;
loop {
let evt = match parser.next() {
Some(e) => e,
None => { break; }
};
let (ref expected_evt, ref expected_stack) = expected[i];
if !parser.stack().is_equal_to(expected_stack.as_slice()) {
fail!("Parser stack is not equal to {}", expected_stack);
}
assert_eq!(&evt, expected_evt);
i+=1;
}
}
#[test]
fn test_streaming_parser() {
assert_stream_equal(
r#"{ "foo":"bar", "array" : [0, 1, 2,3 ,4,5], "idents":[null,true,false]}"#,
~[
(ObjectStart, ~[]),
(StringValue("bar".to_string()), ~[Key("foo")]),
(ListStart, ~[Key("array")]),
(NumberValue(0.0), ~[Key("array"), Index(0)]),
(NumberValue(1.0), ~[Key("array"), Index(1)]),
(NumberValue(2.0), ~[Key("array"), Index(2)]),
(NumberValue(3.0), ~[Key("array"), Index(3)]),
(NumberValue(4.0), ~[Key("array"), Index(4)]),
(NumberValue(5.0), ~[Key("array"), Index(5)]),
(ListEnd, ~[Key("array")]),
(ListStart, ~[Key("idents")]),
(NullValue, ~[Key("idents"), Index(0)]),
(BooleanValue(true), ~[Key("idents"), Index(1)]),
(BooleanValue(false), ~[Key("idents"), Index(2)]),
(ListEnd, ~[Key("idents")]),
(ObjectEnd, ~[]),
]
);
}
fn last_event(src: &str) -> JsonEvent {
let mut parser = Parser::new(src.chars());
let mut evt = NullValue;
loop {
evt = match parser.next() {
Some(e) => e,
None => return evt,
}
}
}
#[test]
#[ignore(cfg(target_word_size = "32"))] // FIXME(#14064)
fn test_read_object_streaming() {
assert_eq!(last_event("{ "), Error(SyntaxError(EOFWhileParsingObject, 1, 3)));
assert_eq!(last_event("{1"), Error(SyntaxError(KeyMustBeAString, 1, 2)));
assert_eq!(last_event("{ \"a\""), Error(SyntaxError(EOFWhileParsingObject, 1, 6)));
assert_eq!(last_event("{\"a\""), Error(SyntaxError(EOFWhileParsingObject, 1, 5)));
assert_eq!(last_event("{\"a\" "), Error(SyntaxError(EOFWhileParsingObject, 1, 6)));
assert_eq!(last_event("{\"a\" 1"), Error(SyntaxError(ExpectedColon, 1, 6)));
assert_eq!(last_event("{\"a\":"), Error(SyntaxError(EOFWhileParsingValue, 1, 6)));
assert_eq!(last_event("{\"a\":1"), Error(SyntaxError(EOFWhileParsingObject, 1, 7)));
assert_eq!(last_event("{\"a\":1 1"), Error(SyntaxError(InvalidSyntax, 1, 8)));
assert_eq!(last_event("{\"a\":1,"), Error(SyntaxError(EOFWhileParsingObject, 1, 8)));
assert_stream_equal(
"{}",
box [(ObjectStart, box []), (ObjectEnd, box [])]
);
assert_stream_equal(
"{\"a\": 3}",
box [
(ObjectStart, box []),
(NumberValue(3.0), box [Key("a")]),
(ObjectEnd, box []),
]
);
assert_stream_equal(
"{ \"a\": null, \"b\" : true }",
box [
(ObjectStart, box []),
(NullValue, box [Key("a")]),
(BooleanValue(true), box [Key("b")]),
(ObjectEnd, box []),
]
);
assert_stream_equal(
"{\"a\" : 1.0 ,\"b\": [ true ]}",
box [
(ObjectStart, box []),
(NumberValue(1.0), box [Key("a")]),
(ListStart, box [Key("b")]),
(BooleanValue(true),box [Key("b"), Index(0)]),
(ListEnd, box [Key("b")]),
(ObjectEnd, box []),
]
);
assert_stream_equal(
r#"{
"a": 1.0,
"b": [
true,
"foo\nbar",
{ "c": {"d": null} }
]
}"#,
~[
(ObjectStart, ~[]),
(NumberValue(1.0), ~[Key("a")]),
(ListStart, ~[Key("b")]),
(BooleanValue(true), ~[Key("b"), Index(0)]),
(StringValue("foo\nbar".to_string()), ~[Key("b"), Index(1)]),
(ObjectStart, ~[Key("b"), Index(2)]),
(ObjectStart, ~[Key("b"), Index(2), Key("c")]),
(NullValue, ~[Key("b"), Index(2), Key("c"), Key("d")]),
(ObjectEnd, ~[Key("b"), Index(2), Key("c")]),
(ObjectEnd, ~[Key("b"), Index(2)]),
(ListEnd, ~[Key("b")]),
(ObjectEnd, ~[]),
]
);
}
#[test]
#[ignore(cfg(target_word_size = "32"))] // FIXME(#14064)
fn test_read_list_streaming() {
assert_stream_equal(
"[]",
box [
(ListStart, box []),
(ListEnd, box []),
]
);
assert_stream_equal(
"[ ]",
box [
(ListStart, box []),
(ListEnd, box []),
]
);
assert_stream_equal(
"[true]",
box [
(ListStart, box []),
(BooleanValue(true), box [Index(0)]),
(ListEnd, box []),
]
);
assert_stream_equal(
"[ false ]",
box [
(ListStart, box []),
(BooleanValue(false), box [Index(0)]),
(ListEnd, box []),
]
);
assert_stream_equal(
"[null]",
box [
(ListStart, box []),
(NullValue, box [Index(0)]),
(ListEnd, box []),
]
);
assert_stream_equal(
"[3, 1]",
box [
(ListStart, box []),
(NumberValue(3.0), box [Index(0)]),
(NumberValue(1.0), box [Index(1)]),
(ListEnd, box []),
]
);
assert_stream_equal(
"\n[3, 2]\n",
box [
(ListStart, box []),
(NumberValue(3.0), box [Index(0)]),
(NumberValue(2.0), box [Index(1)]),
(ListEnd, box []),
]
);
assert_stream_equal(
"[2, [4, 1]]",
box [
(ListStart, box []),
(NumberValue(2.0), box [Index(0)]),
(ListStart, box [Index(1)]),
(NumberValue(4.0), box [Index(1), Index(0)]),
(NumberValue(1.0), box [Index(1), Index(1)]),
(ListEnd, box [Index(1)]),
(ListEnd, box []),
]
);
assert_eq!(last_event("["), Error(SyntaxError(EOFWhileParsingValue, 1, 2)));
assert_eq!(from_str("["), Err(SyntaxError(EOFWhileParsingValue, 1, 2)));
assert_eq!(from_str("[1"), Err(SyntaxError(EOFWhileParsingList, 1, 3)));
assert_eq!(from_str("[1,"), Err(SyntaxError(EOFWhileParsingValue, 1, 4)));
assert_eq!(from_str("[1,]"), Err(SyntaxError(InvalidSyntax, 1, 4)));
assert_eq!(from_str("[6 7]"), Err(SyntaxError(InvalidSyntax, 1, 4)));
}
#[test]
fn test_trailing_characters_streaming() {
assert_eq!(last_event("nulla"), Error(SyntaxError(TrailingCharacters, 1, 5)));
assert_eq!(last_event("truea"), Error(SyntaxError(TrailingCharacters, 1, 5)));
assert_eq!(last_event("falsea"), Error(SyntaxError(TrailingCharacters, 1, 6)));
assert_eq!(last_event("1a"), Error(SyntaxError(TrailingCharacters, 1, 2)));
assert_eq!(last_event("[]a"), Error(SyntaxError(TrailingCharacters, 1, 3)));
assert_eq!(last_event("{}a"), Error(SyntaxError(TrailingCharacters, 1, 3)));
}
#[test]
fn test_read_identifiers_streaming() {
assert_eq!(Parser::new("null".chars()).next(), Some(NullValue));
assert_eq!(Parser::new("true".chars()).next(), Some(BooleanValue(true)));
assert_eq!(Parser::new("false".chars()).next(), Some(BooleanValue(false)));
assert_eq!(last_event("n"), Error(SyntaxError(InvalidSyntax, 1, 2)));
assert_eq!(last_event("nul"), Error(SyntaxError(InvalidSyntax, 1, 4)));
assert_eq!(last_event("t"), Error(SyntaxError(InvalidSyntax, 1, 2)));
assert_eq!(last_event("truz"), Error(SyntaxError(InvalidSyntax, 1, 4)));
assert_eq!(last_event("f"), Error(SyntaxError(InvalidSyntax, 1, 2)));
assert_eq!(last_event("faz"), Error(SyntaxError(InvalidSyntax, 1, 3)));
}
#[test]
fn test_stack() {
let mut stack = Stack::new();
assert!(stack.is_empty());
assert!(stack.len() == 0);
assert!(!stack.last_is_index());
stack.push_index(0);
stack.bump_index();
assert!(stack.len() == 1);
assert!(stack.is_equal_to([Index(1)]));
assert!(stack.starts_with([Index(1)]));
assert!(stack.ends_with([Index(1)]));
assert!(stack.last_is_index());
assert!(stack.get(0) == Index(1));
stack.push_key("foo".to_string());
assert!(stack.len() == 2);
assert!(stack.is_equal_to([Index(1), Key("foo")]));
assert!(stack.starts_with([Index(1), Key("foo")]));
assert!(stack.starts_with([Index(1)]));
assert!(stack.ends_with([Index(1), Key("foo")]));
assert!(stack.ends_with([Key("foo")]));
assert!(!stack.last_is_index());
assert!(stack.get(0) == Index(1));
assert!(stack.get(1) == Key("foo"));
stack.push_key("bar".to_string());
assert!(stack.len() == 3);
assert!(stack.is_equal_to([Index(1), Key("foo"), Key("bar")]));
assert!(stack.starts_with([Index(1)]));
assert!(stack.starts_with([Index(1), Key("foo")]));
assert!(stack.starts_with([Index(1), Key("foo"), Key("bar")]));
assert!(stack.ends_with([Key("bar")]));
assert!(stack.ends_with([Key("foo"), Key("bar")]));
assert!(stack.ends_with([Index(1), Key("foo"), Key("bar")]));
assert!(!stack.last_is_index());
assert!(stack.get(0) == Index(1));
assert!(stack.get(1) == Key("foo"));
assert!(stack.get(2) == Key("bar"));
stack.pop();
assert!(stack.len() == 2);
assert!(stack.is_equal_to([Index(1), Key("foo")]));
assert!(stack.starts_with([Index(1), Key("foo")]));
assert!(stack.starts_with([Index(1)]));
assert!(stack.ends_with([Index(1), Key("foo")]));
assert!(stack.ends_with([Key("foo")]));
assert!(!stack.last_is_index());
assert!(stack.get(0) == Index(1));
assert!(stack.get(1) == Key("foo"));
}
#[bench]
fn bench_streaming_small(b: &mut Bencher) {
b.iter( || {
let mut parser = Parser::new(
r#"{
"a": 1.0,
"b": [
true,
"foo\nbar",
{ "c": {"d": null} }
]
}"#.chars()
);
loop {
match parser.next() {
None => return,
_ => {}
}
}
});
}
#[bench]
fn bench_small(b: &mut Bencher) {
b.iter( || {
let _ = from_str(r#"{
"a": 1.0,
"b": [
true,
"foo\nbar",
{ "c": {"d": null} }
]
}"#);
});
}
fn big_json() -> String {
let mut src = "[\n".to_string();
for _ in range(0, 500) {
src.push_str(r#"{ "a": true, "b": null, "c":3.1415, "d": "Hello world", "e": \
[1,2,3]},"#);
}
src.push_str("{}]");
return src;
}
#[bench]
fn bench_streaming_large(b: &mut Bencher) {
let src = big_json();
b.iter( || {
let mut parser = Parser::new(src.as_slice().chars());
loop {
match parser.next() {
None => return,
_ => {}
}
}
});
}
#[bench]
fn bench_large(b: &mut Bencher) {
let src = big_json();
b.iter( || { let _ = from_str(src.as_slice()); });
}
*/
}