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Diffstat (limited to 'vendor/serde_json/src/de.rs')
| -rw-r--r-- | vendor/serde_json/src/de.rs | 2679 |
1 files changed, 0 insertions, 2679 deletions
diff --git a/vendor/serde_json/src/de.rs b/vendor/serde_json/src/de.rs deleted file mode 100644 index 7154f84..0000000 --- a/vendor/serde_json/src/de.rs +++ /dev/null @@ -1,2679 +0,0 @@ -//! Deserialize JSON data to a Rust data structure. - -use crate::error::{Error, ErrorCode, Result}; -#[cfg(feature = "float_roundtrip")] -use crate::lexical; -use crate::number::Number; -use crate::read::{self, Fused, Reference}; -use alloc::string::String; -use alloc::vec::Vec; -#[cfg(feature = "float_roundtrip")] -use core::iter; -use core::iter::FusedIterator; -use core::marker::PhantomData; -use core::result; -use core::str::FromStr; -use serde::de::{self, Expected, Unexpected}; -use serde::forward_to_deserialize_any; - -#[cfg(feature = "arbitrary_precision")] -use crate::number::NumberDeserializer; - -pub use crate::read::{Read, SliceRead, StrRead}; - -#[cfg(feature = "std")] -#[cfg_attr(docsrs, doc(cfg(feature = "std")))] -pub use crate::read::IoRead; - -////////////////////////////////////////////////////////////////////////////// - -/// A structure that deserializes JSON into Rust values. -pub struct Deserializer<R> { - read: R, - scratch: Vec<u8>, - remaining_depth: u8, - #[cfg(feature = "float_roundtrip")] - single_precision: bool, - #[cfg(feature = "unbounded_depth")] - disable_recursion_limit: bool, -} - -impl<'de, R> Deserializer<R> -where - R: read::Read<'de>, -{ - /// Create a JSON deserializer from one of the possible serde_json input - /// sources. - /// - /// Typically it is more convenient to use one of these methods instead: - /// - /// - Deserializer::from_str - /// - Deserializer::from_slice - /// - Deserializer::from_reader - pub fn new(read: R) -> Self { - Deserializer { - read, - scratch: Vec::new(), - remaining_depth: 128, - #[cfg(feature = "float_roundtrip")] - single_precision: false, - #[cfg(feature = "unbounded_depth")] - disable_recursion_limit: false, - } - } -} - -#[cfg(feature = "std")] -impl<R> Deserializer<read::IoRead<R>> -where - R: crate::io::Read, -{ - /// Creates a JSON deserializer from an `io::Read`. - /// - /// Reader-based deserializers do not support deserializing borrowed types - /// like `&str`, since the `std::io::Read` trait has no non-copying methods - /// -- everything it does involves copying bytes out of the data source. - pub fn from_reader(reader: R) -> Self { - Deserializer::new(read::IoRead::new(reader)) - } -} - -impl<'a> Deserializer<read::SliceRead<'a>> { - /// Creates a JSON deserializer from a `&[u8]`. - pub fn from_slice(bytes: &'a [u8]) -> Self { - Deserializer::new(read::SliceRead::new(bytes)) - } -} - -impl<'a> Deserializer<read::StrRead<'a>> { - /// Creates a JSON deserializer from a `&str`. - pub fn from_str(s: &'a str) -> Self { - Deserializer::new(read::StrRead::new(s)) - } -} - -macro_rules! overflow { - ($a:ident * 10 + $b:ident, $c:expr) => { - match $c { - c => $a >= c / 10 && ($a > c / 10 || $b > c % 10), - } - }; -} - -pub(crate) enum ParserNumber { - F64(f64), - U64(u64), - I64(i64), - #[cfg(feature = "arbitrary_precision")] - String(String), -} - -impl ParserNumber { - fn visit<'de, V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - match self { - ParserNumber::F64(x) => visitor.visit_f64(x), - ParserNumber::U64(x) => visitor.visit_u64(x), - ParserNumber::I64(x) => visitor.visit_i64(x), - #[cfg(feature = "arbitrary_precision")] - ParserNumber::String(x) => visitor.visit_map(NumberDeserializer { number: x.into() }), - } - } - - fn invalid_type(self, exp: &dyn Expected) -> Error { - match self { - ParserNumber::F64(x) => de::Error::invalid_type(Unexpected::Float(x), exp), - ParserNumber::U64(x) => de::Error::invalid_type(Unexpected::Unsigned(x), exp), - ParserNumber::I64(x) => de::Error::invalid_type(Unexpected::Signed(x), exp), - #[cfg(feature = "arbitrary_precision")] - ParserNumber::String(_) => de::Error::invalid_type(Unexpected::Other("number"), exp), - } - } -} - -impl<'de, R: Read<'de>> Deserializer<R> { - /// The `Deserializer::end` method should be called after a value has been fully deserialized. - /// This allows the `Deserializer` to validate that the input stream is at the end or that it - /// only has trailing whitespace. - pub fn end(&mut self) -> Result<()> { - match tri!(self.parse_whitespace()) { - Some(_) => Err(self.peek_error(ErrorCode::TrailingCharacters)), - None => Ok(()), - } - } - - /// Turn a JSON deserializer into an iterator over values of type T. - pub fn into_iter<T>(self) -> StreamDeserializer<'de, R, T> - where - T: de::Deserialize<'de>, - { - // This cannot be an implementation of std::iter::IntoIterator because - // we need the caller to choose what T is. - let offset = self.read.byte_offset(); - StreamDeserializer { - de: self, - offset, - failed: false, - output: PhantomData, - lifetime: PhantomData, - } - } - - /// Parse arbitrarily deep JSON structures without any consideration for - /// overflowing the stack. - /// - /// You will want to provide some other way to protect against stack - /// overflows, such as by wrapping your Deserializer in the dynamically - /// growing stack adapter provided by the serde_stacker crate. Additionally - /// you will need to be careful around other recursive operations on the - /// parsed result which may overflow the stack after deserialization has - /// completed, including, but not limited to, Display and Debug and Drop - /// impls. - /// - /// *This method is only available if serde_json is built with the - /// `"unbounded_depth"` feature.* - /// - /// # Examples - /// - /// ``` - /// use serde::Deserialize; - /// use serde_json::Value; - /// - /// fn main() { - /// let mut json = String::new(); - /// for _ in 0..10000 { - /// json = format!("[{}]", json); - /// } - /// - /// let mut deserializer = serde_json::Deserializer::from_str(&json); - /// deserializer.disable_recursion_limit(); - /// let deserializer = serde_stacker::Deserializer::new(&mut deserializer); - /// let value = Value::deserialize(deserializer).unwrap(); - /// - /// carefully_drop_nested_arrays(value); - /// } - /// - /// fn carefully_drop_nested_arrays(value: Value) { - /// let mut stack = vec![value]; - /// while let Some(value) = stack.pop() { - /// if let Value::Array(array) = value { - /// stack.extend(array); - /// } - /// } - /// } - /// ``` - #[cfg(feature = "unbounded_depth")] - #[cfg_attr(docsrs, doc(cfg(feature = "unbounded_depth")))] - pub fn disable_recursion_limit(&mut self) { - self.disable_recursion_limit = true; - } - - pub(crate) fn peek(&mut self) -> Result<Option<u8>> { - self.read.peek() - } - - fn peek_or_null(&mut self) -> Result<u8> { - Ok(tri!(self.peek()).unwrap_or(b'\x00')) - } - - fn eat_char(&mut self) { - self.read.discard(); - } - - fn next_char(&mut self) -> Result<Option<u8>> { - self.read.next() - } - - fn next_char_or_null(&mut self) -> Result<u8> { - Ok(tri!(self.next_char()).unwrap_or(b'\x00')) - } - - /// Error caused by a byte from next_char(). - #[cold] - fn error(&self, reason: ErrorCode) -> Error { - let position = self.read.position(); - Error::syntax(reason, position.line, position.column) - } - - /// Error caused by a byte from peek(). - #[cold] - fn peek_error(&self, reason: ErrorCode) -> Error { - let position = self.read.peek_position(); - Error::syntax(reason, position.line, position.column) - } - - /// Returns the first non-whitespace byte without consuming it, or `None` if - /// EOF is encountered. - fn parse_whitespace(&mut self) -> Result<Option<u8>> { - loop { - match tri!(self.peek()) { - Some(b' ' | b'\n' | b'\t' | b'\r') => { - self.eat_char(); - } - other => { - return Ok(other); - } - } - } - } - - #[cold] - fn peek_invalid_type(&mut self, exp: &dyn Expected) -> Error { - let err = match self.peek_or_null().unwrap_or(b'\x00') { - b'n' => { - self.eat_char(); - if let Err(err) = self.parse_ident(b"ull") { - return err; - } - de::Error::invalid_type(Unexpected::Unit, exp) - } - b't' => { - self.eat_char(); - if let Err(err) = self.parse_ident(b"rue") { - return err; - } - de::Error::invalid_type(Unexpected::Bool(true), exp) - } - b'f' => { - self.eat_char(); - if let Err(err) = self.parse_ident(b"alse") { - return err; - } - de::Error::invalid_type(Unexpected::Bool(false), exp) - } - b'-' => { - self.eat_char(); - match self.parse_any_number(false) { - Ok(n) => n.invalid_type(exp), - Err(err) => return err, - } - } - b'0'..=b'9' => match self.parse_any_number(true) { - Ok(n) => n.invalid_type(exp), - Err(err) => return err, - }, - b'"' => { - self.eat_char(); - self.scratch.clear(); - match self.read.parse_str(&mut self.scratch) { - Ok(s) => de::Error::invalid_type(Unexpected::Str(&s), exp), - Err(err) => return err, - } - } - b'[' => de::Error::invalid_type(Unexpected::Seq, exp), - b'{' => de::Error::invalid_type(Unexpected::Map, exp), - _ => self.peek_error(ErrorCode::ExpectedSomeValue), - }; - - self.fix_position(err) - } - - pub(crate) fn deserialize_number<'any, V>(&mut self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'any>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'-' => { - self.eat_char(); - tri!(self.parse_integer(false)).visit(visitor) - } - b'0'..=b'9' => tri!(self.parse_integer(true)).visit(visitor), - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - #[cfg(feature = "float_roundtrip")] - pub(crate) fn do_deserialize_f32<'any, V>(&mut self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'any>, - { - self.single_precision = true; - let val = self.deserialize_number(visitor); - self.single_precision = false; - val - } - - pub(crate) fn do_deserialize_i128<'any, V>(&mut self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'any>, - { - let mut buf = String::new(); - - match tri!(self.parse_whitespace()) { - Some(b'-') => { - self.eat_char(); - buf.push('-'); - } - Some(_) => {} - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - tri!(self.scan_integer128(&mut buf)); - - let value = match buf.parse() { - Ok(int) => visitor.visit_i128(int), - Err(_) => { - return Err(self.error(ErrorCode::NumberOutOfRange)); - } - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - pub(crate) fn do_deserialize_u128<'any, V>(&mut self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'any>, - { - match tri!(self.parse_whitespace()) { - Some(b'-') => { - return Err(self.peek_error(ErrorCode::NumberOutOfRange)); - } - Some(_) => {} - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - } - - let mut buf = String::new(); - tri!(self.scan_integer128(&mut buf)); - - let value = match buf.parse() { - Ok(int) => visitor.visit_u128(int), - Err(_) => { - return Err(self.error(ErrorCode::NumberOutOfRange)); - } - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - fn scan_integer128(&mut self, buf: &mut String) -> Result<()> { - match tri!(self.next_char_or_null()) { - b'0' => { - buf.push('0'); - // There can be only one leading '0'. - match tri!(self.peek_or_null()) { - b'0'..=b'9' => Err(self.peek_error(ErrorCode::InvalidNumber)), - _ => Ok(()), - } - } - c @ b'1'..=b'9' => { - buf.push(c as char); - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - buf.push(c as char); - } - Ok(()) - } - _ => Err(self.error(ErrorCode::InvalidNumber)), - } - } - - #[cold] - fn fix_position(&self, err: Error) -> Error { - err.fix_position(move |code| self.error(code)) - } - - fn parse_ident(&mut self, ident: &[u8]) -> Result<()> { - for expected in ident { - match tri!(self.next_char()) { - None => { - return Err(self.error(ErrorCode::EofWhileParsingValue)); - } - Some(next) => { - if next != *expected { - return Err(self.error(ErrorCode::ExpectedSomeIdent)); - } - } - } - } - - Ok(()) - } - - fn parse_integer(&mut self, positive: bool) -> Result<ParserNumber> { - let next = match tri!(self.next_char()) { - Some(b) => b, - None => { - return Err(self.error(ErrorCode::EofWhileParsingValue)); - } - }; - - match next { - b'0' => { - // There can be only one leading '0'. - match tri!(self.peek_or_null()) { - b'0'..=b'9' => Err(self.peek_error(ErrorCode::InvalidNumber)), - _ => self.parse_number(positive, 0), - } - } - c @ b'1'..=b'9' => { - let mut significand = (c - b'0') as u64; - - loop { - match tri!(self.peek_or_null()) { - c @ b'0'..=b'9' => { - let digit = (c - b'0') as u64; - - // We need to be careful with overflow. If we can, - // try to keep the number as a `u64` until we grow - // too large. At that point, switch to parsing the - // value as a `f64`. - if overflow!(significand * 10 + digit, u64::max_value()) { - return Ok(ParserNumber::F64(tri!( - self.parse_long_integer(positive, significand), - ))); - } - - self.eat_char(); - significand = significand * 10 + digit; - } - _ => { - return self.parse_number(positive, significand); - } - } - } - } - _ => Err(self.error(ErrorCode::InvalidNumber)), - } - } - - fn parse_number(&mut self, positive: bool, significand: u64) -> Result<ParserNumber> { - Ok(match tri!(self.peek_or_null()) { - b'.' => ParserNumber::F64(tri!(self.parse_decimal(positive, significand, 0))), - b'e' | b'E' => ParserNumber::F64(tri!(self.parse_exponent(positive, significand, 0))), - _ => { - if positive { - ParserNumber::U64(significand) - } else { - let neg = (significand as i64).wrapping_neg(); - - // Convert into a float if we underflow, or on `-0`. - if neg >= 0 { - ParserNumber::F64(-(significand as f64)) - } else { - ParserNumber::I64(neg) - } - } - } - }) - } - - fn parse_decimal( - &mut self, - positive: bool, - mut significand: u64, - exponent_before_decimal_point: i32, - ) -> Result<f64> { - self.eat_char(); - - let mut exponent_after_decimal_point = 0; - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - let digit = (c - b'0') as u64; - - if overflow!(significand * 10 + digit, u64::max_value()) { - let exponent = exponent_before_decimal_point + exponent_after_decimal_point; - return self.parse_decimal_overflow(positive, significand, exponent); - } - - self.eat_char(); - significand = significand * 10 + digit; - exponent_after_decimal_point -= 1; - } - - // Error if there is not at least one digit after the decimal point. - if exponent_after_decimal_point == 0 { - match tri!(self.peek()) { - Some(_) => return Err(self.peek_error(ErrorCode::InvalidNumber)), - None => return Err(self.peek_error(ErrorCode::EofWhileParsingValue)), - } - } - - let exponent = exponent_before_decimal_point + exponent_after_decimal_point; - match tri!(self.peek_or_null()) { - b'e' | b'E' => self.parse_exponent(positive, significand, exponent), - _ => self.f64_from_parts(positive, significand, exponent), - } - } - - fn parse_exponent( - &mut self, - positive: bool, - significand: u64, - starting_exp: i32, - ) -> Result<f64> { - self.eat_char(); - - let positive_exp = match tri!(self.peek_or_null()) { - b'+' => { - self.eat_char(); - true - } - b'-' => { - self.eat_char(); - false - } - _ => true, - }; - - let next = match tri!(self.next_char()) { - Some(b) => b, - None => { - return Err(self.error(ErrorCode::EofWhileParsingValue)); - } - }; - - // Make sure a digit follows the exponent place. - let mut exp = match next { - c @ b'0'..=b'9' => (c - b'0') as i32, - _ => { - return Err(self.error(ErrorCode::InvalidNumber)); - } - }; - - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - let digit = (c - b'0') as i32; - - if overflow!(exp * 10 + digit, i32::max_value()) { - let zero_significand = significand == 0; - return self.parse_exponent_overflow(positive, zero_significand, positive_exp); - } - - exp = exp * 10 + digit; - } - - let final_exp = if positive_exp { - starting_exp.saturating_add(exp) - } else { - starting_exp.saturating_sub(exp) - }; - - self.f64_from_parts(positive, significand, final_exp) - } - - #[cfg(feature = "float_roundtrip")] - fn f64_from_parts(&mut self, positive: bool, significand: u64, exponent: i32) -> Result<f64> { - let f = if self.single_precision { - lexical::parse_concise_float::<f32>(significand, exponent) as f64 - } else { - lexical::parse_concise_float::<f64>(significand, exponent) - }; - - if f.is_infinite() { - Err(self.error(ErrorCode::NumberOutOfRange)) - } else { - Ok(if positive { f } else { -f }) - } - } - - #[cfg(not(feature = "float_roundtrip"))] - fn f64_from_parts( - &mut self, - positive: bool, - significand: u64, - mut exponent: i32, - ) -> Result<f64> { - let mut f = significand as f64; - loop { - match POW10.get(exponent.wrapping_abs() as usize) { - Some(&pow) => { - if exponent >= 0 { - f *= pow; - if f.is_infinite() { - return Err(self.error(ErrorCode::NumberOutOfRange)); - } - } else { - f /= pow; - } - break; - } - None => { - if f == 0.0 { - break; - } - if exponent >= 0 { - return Err(self.error(ErrorCode::NumberOutOfRange)); - } - f /= 1e308; - exponent += 308; - } - } - } - Ok(if positive { f } else { -f }) - } - - #[cfg(feature = "float_roundtrip")] - #[cold] - #[inline(never)] - fn parse_long_integer(&mut self, positive: bool, partial_significand: u64) -> Result<f64> { - // To deserialize floats we'll first push the integer and fraction - // parts, both as byte strings, into the scratch buffer and then feed - // both slices to lexical's parser. For example if the input is - // `12.34e5` we'll push b"1234" into scratch and then pass b"12" and - // b"34" to lexical. `integer_end` will be used to track where to split - // the scratch buffer. - // - // Note that lexical expects the integer part to contain *no* leading - // zeroes and the fraction part to contain *no* trailing zeroes. The - // first requirement is already handled by the integer parsing logic. - // The second requirement will be enforced just before passing the - // slices to lexical in f64_long_from_parts. - self.scratch.clear(); - self.scratch - .extend_from_slice(itoa::Buffer::new().format(partial_significand).as_bytes()); - - loop { - match tri!(self.peek_or_null()) { - c @ b'0'..=b'9' => { - self.scratch.push(c); - self.eat_char(); - } - b'.' => { - self.eat_char(); - return self.parse_long_decimal(positive, self.scratch.len()); - } - b'e' | b'E' => { - return self.parse_long_exponent(positive, self.scratch.len()); - } - _ => { - return self.f64_long_from_parts(positive, self.scratch.len(), 0); - } - } - } - } - - #[cfg(not(feature = "float_roundtrip"))] - #[cold] - #[inline(never)] - fn parse_long_integer(&mut self, positive: bool, significand: u64) -> Result<f64> { - let mut exponent = 0; - loop { - match tri!(self.peek_or_null()) { - b'0'..=b'9' => { - self.eat_char(); - // This could overflow... if your integer is gigabytes long. - // Ignore that possibility. - exponent += 1; - } - b'.' => { - return self.parse_decimal(positive, significand, exponent); - } - b'e' | b'E' => { - return self.parse_exponent(positive, significand, exponent); - } - _ => { - return self.f64_from_parts(positive, significand, exponent); - } - } - } - } - - #[cfg(feature = "float_roundtrip")] - #[cold] - fn parse_long_decimal(&mut self, positive: bool, integer_end: usize) -> Result<f64> { - let mut at_least_one_digit = integer_end < self.scratch.len(); - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - self.scratch.push(c); - self.eat_char(); - at_least_one_digit = true; - } - - if !at_least_one_digit { - match tri!(self.peek()) { - Some(_) => return Err(self.peek_error(ErrorCode::InvalidNumber)), - None => return Err(self.peek_error(ErrorCode::EofWhileParsingValue)), - } - } - - match tri!(self.peek_or_null()) { - b'e' | b'E' => self.parse_long_exponent(positive, integer_end), - _ => self.f64_long_from_parts(positive, integer_end, 0), - } - } - - #[cfg(feature = "float_roundtrip")] - fn parse_long_exponent(&mut self, positive: bool, integer_end: usize) -> Result<f64> { - self.eat_char(); - - let positive_exp = match tri!(self.peek_or_null()) { - b'+' => { - self.eat_char(); - true - } - b'-' => { - self.eat_char(); - false - } - _ => true, - }; - - let next = match tri!(self.next_char()) { - Some(b) => b, - None => { - return Err(self.error(ErrorCode::EofWhileParsingValue)); - } - }; - - // Make sure a digit follows the exponent place. - let mut exp = match next { - c @ b'0'..=b'9' => (c - b'0') as i32, - _ => { - return Err(self.error(ErrorCode::InvalidNumber)); - } - }; - - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - let digit = (c - b'0') as i32; - - if overflow!(exp * 10 + digit, i32::max_value()) { - let zero_significand = self.scratch.iter().all(|&digit| digit == b'0'); - return self.parse_exponent_overflow(positive, zero_significand, positive_exp); - } - - exp = exp * 10 + digit; - } - - let final_exp = if positive_exp { exp } else { -exp }; - - self.f64_long_from_parts(positive, integer_end, final_exp) - } - - // This cold code should not be inlined into the middle of the hot - // decimal-parsing loop above. - #[cfg(feature = "float_roundtrip")] - #[cold] - #[inline(never)] - fn parse_decimal_overflow( - &mut self, - positive: bool, - significand: u64, - exponent: i32, - ) -> Result<f64> { - let mut buffer = itoa::Buffer::new(); - let significand = buffer.format(significand); - let fraction_digits = -exponent as usize; - self.scratch.clear(); - if let Some(zeros) = fraction_digits.checked_sub(significand.len() + 1) { - self.scratch.extend(iter::repeat(b'0').take(zeros + 1)); - } - self.scratch.extend_from_slice(significand.as_bytes()); - let integer_end = self.scratch.len() - fraction_digits; - self.parse_long_decimal(positive, integer_end) - } - - #[cfg(not(feature = "float_roundtrip"))] - #[cold] - #[inline(never)] - fn parse_decimal_overflow( - &mut self, - positive: bool, - significand: u64, - exponent: i32, - ) -> Result<f64> { - // The next multiply/add would overflow, so just ignore all further - // digits. - while let b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - } - - match tri!(self.peek_or_null()) { - b'e' | b'E' => self.parse_exponent(positive, significand, exponent), - _ => self.f64_from_parts(positive, significand, exponent), - } - } - - // This cold code should not be inlined into the middle of the hot - // exponent-parsing loop above. - #[cold] - #[inline(never)] - fn parse_exponent_overflow( - &mut self, - positive: bool, - zero_significand: bool, - positive_exp: bool, - ) -> Result<f64> { - // Error instead of +/- infinity. - if !zero_significand && positive_exp { - return Err(self.error(ErrorCode::NumberOutOfRange)); - } - - while let b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - } - Ok(if positive { 0.0 } else { -0.0 }) - } - - #[cfg(feature = "float_roundtrip")] - fn f64_long_from_parts( - &mut self, - positive: bool, - integer_end: usize, - exponent: i32, - ) -> Result<f64> { - let integer = &self.scratch[..integer_end]; - let fraction = &self.scratch[integer_end..]; - - let f = if self.single_precision { - lexical::parse_truncated_float::<f32>(integer, fraction, exponent) as f64 - } else { - lexical::parse_truncated_float::<f64>(integer, fraction, exponent) - }; - - if f.is_infinite() { - Err(self.error(ErrorCode::NumberOutOfRange)) - } else { - Ok(if positive { f } else { -f }) - } - } - - fn parse_any_signed_number(&mut self) -> Result<ParserNumber> { - let peek = match tri!(self.peek()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'-' => { - self.eat_char(); - self.parse_any_number(false) - } - b'0'..=b'9' => self.parse_any_number(true), - _ => Err(self.peek_error(ErrorCode::InvalidNumber)), - }; - - let value = match tri!(self.peek()) { - Some(_) => Err(self.peek_error(ErrorCode::InvalidNumber)), - None => value, - }; - - match value { - Ok(value) => Ok(value), - // The de::Error impl creates errors with unknown line and column. - // Fill in the position here by looking at the current index in the - // input. There is no way to tell whether this should call `error` - // or `peek_error` so pick the one that seems correct more often. - // Worst case, the position is off by one character. - Err(err) => Err(self.fix_position(err)), - } - } - - #[cfg(not(feature = "arbitrary_precision"))] - fn parse_any_number(&mut self, positive: bool) -> Result<ParserNumber> { - self.parse_integer(positive) - } - - #[cfg(feature = "arbitrary_precision")] - fn parse_any_number(&mut self, positive: bool) -> Result<ParserNumber> { - let mut buf = String::with_capacity(16); - if !positive { - buf.push('-'); - } - tri!(self.scan_integer(&mut buf)); - if positive { - if let Ok(unsigned) = buf.parse() { - return Ok(ParserNumber::U64(unsigned)); - } - } else { - if let Ok(signed) = buf.parse() { - return Ok(ParserNumber::I64(signed)); - } - } - Ok(ParserNumber::String(buf)) - } - - #[cfg(feature = "arbitrary_precision")] - fn scan_or_eof(&mut self, buf: &mut String) -> Result<u8> { - match tri!(self.next_char()) { - Some(b) => { - buf.push(b as char); - Ok(b) - } - None => Err(self.error(ErrorCode::EofWhileParsingValue)), - } - } - - #[cfg(feature = "arbitrary_precision")] - fn scan_integer(&mut self, buf: &mut String) -> Result<()> { - match tri!(self.scan_or_eof(buf)) { - b'0' => { - // There can be only one leading '0'. - match tri!(self.peek_or_null()) { - b'0'..=b'9' => Err(self.peek_error(ErrorCode::InvalidNumber)), - _ => self.scan_number(buf), - } - } - b'1'..=b'9' => loop { - match tri!(self.peek_or_null()) { - c @ b'0'..=b'9' => { - self.eat_char(); - buf.push(c as char); - } - _ => { - return self.scan_number(buf); - } - } - }, - _ => Err(self.error(ErrorCode::InvalidNumber)), - } - } - - #[cfg(feature = "arbitrary_precision")] - fn scan_number(&mut self, buf: &mut String) -> Result<()> { - match tri!(self.peek_or_null()) { - b'.' => self.scan_decimal(buf), - e @ (b'e' | b'E') => self.scan_exponent(e as char, buf), - _ => Ok(()), - } - } - - #[cfg(feature = "arbitrary_precision")] - fn scan_decimal(&mut self, buf: &mut String) -> Result<()> { - self.eat_char(); - buf.push('.'); - - let mut at_least_one_digit = false; - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - buf.push(c as char); - at_least_one_digit = true; - } - - if !at_least_one_digit { - match tri!(self.peek()) { - Some(_) => return Err(self.peek_error(ErrorCode::InvalidNumber)), - None => return Err(self.peek_error(ErrorCode::EofWhileParsingValue)), - } - } - - match tri!(self.peek_or_null()) { - e @ (b'e' | b'E') => self.scan_exponent(e as char, buf), - _ => Ok(()), - } - } - - #[cfg(feature = "arbitrary_precision")] - fn scan_exponent(&mut self, e: char, buf: &mut String) -> Result<()> { - self.eat_char(); - buf.push(e); - - match tri!(self.peek_or_null()) { - b'+' => { - self.eat_char(); - buf.push('+'); - } - b'-' => { - self.eat_char(); - buf.push('-'); - } - _ => {} - } - - // Make sure a digit follows the exponent place. - match tri!(self.scan_or_eof(buf)) { - b'0'..=b'9' => {} - _ => { - return Err(self.error(ErrorCode::InvalidNumber)); - } - } - - while let c @ b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - buf.push(c as char); - } - - Ok(()) - } - - fn parse_object_colon(&mut self) -> Result<()> { - match tri!(self.parse_whitespace()) { - Some(b':') => { - self.eat_char(); - Ok(()) - } - Some(_) => Err(self.peek_error(ErrorCode::ExpectedColon)), - None => Err(self.peek_error(ErrorCode::EofWhileParsingObject)), - } - } - - fn end_seq(&mut self) -> Result<()> { - match tri!(self.parse_whitespace()) { - Some(b']') => { - self.eat_char(); - Ok(()) - } - Some(b',') => { - self.eat_char(); - match self.parse_whitespace() { - Ok(Some(b']')) => Err(self.peek_error(ErrorCode::TrailingComma)), - _ => Err(self.peek_error(ErrorCode::TrailingCharacters)), - } - } - Some(_) => Err(self.peek_error(ErrorCode::TrailingCharacters)), - None => Err(self.peek_error(ErrorCode::EofWhileParsingList)), - } - } - - fn end_map(&mut self) -> Result<()> { - match tri!(self.parse_whitespace()) { - Some(b'}') => { - self.eat_char(); - Ok(()) - } - Some(b',') => Err(self.peek_error(ErrorCode::TrailingComma)), - Some(_) => Err(self.peek_error(ErrorCode::TrailingCharacters)), - None => Err(self.peek_error(ErrorCode::EofWhileParsingObject)), - } - } - - fn ignore_value(&mut self) -> Result<()> { - self.scratch.clear(); - let mut enclosing = None; - - loop { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let frame = match peek { - b'n' => { - self.eat_char(); - tri!(self.parse_ident(b"ull")); - None - } - b't' => { - self.eat_char(); - tri!(self.parse_ident(b"rue")); - None - } - b'f' => { - self.eat_char(); - tri!(self.parse_ident(b"alse")); - None - } - b'-' => { - self.eat_char(); - tri!(self.ignore_integer()); - None - } - b'0'..=b'9' => { - tri!(self.ignore_integer()); - None - } - b'"' => { - self.eat_char(); - tri!(self.read.ignore_str()); - None - } - frame @ (b'[' | b'{') => { - self.scratch.extend(enclosing.take()); - self.eat_char(); - Some(frame) - } - _ => return Err(self.peek_error(ErrorCode::ExpectedSomeValue)), - }; - - let (mut accept_comma, mut frame) = match frame { - Some(frame) => (false, frame), - None => match enclosing.take() { - Some(frame) => (true, frame), - None => match self.scratch.pop() { - Some(frame) => (true, frame), - None => return Ok(()), - }, - }, - }; - - loop { - match tri!(self.parse_whitespace()) { - Some(b',') if accept_comma => { - self.eat_char(); - break; - } - Some(b']') if frame == b'[' => {} - Some(b'}') if frame == b'{' => {} - Some(_) => { - if accept_comma { - return Err(self.peek_error(match frame { - b'[' => ErrorCode::ExpectedListCommaOrEnd, - b'{' => ErrorCode::ExpectedObjectCommaOrEnd, - _ => unreachable!(), - })); - } else { - break; - } - } - None => { - return Err(self.peek_error(match frame { - b'[' => ErrorCode::EofWhileParsingList, - b'{' => ErrorCode::EofWhileParsingObject, - _ => unreachable!(), - })); - } - } - - self.eat_char(); - frame = match self.scratch.pop() { - Some(frame) => frame, - None => return Ok(()), - }; - accept_comma = true; - } - - if frame == b'{' { - match tri!(self.parse_whitespace()) { - Some(b'"') => self.eat_char(), - Some(_) => return Err(self.peek_error(ErrorCode::KeyMustBeAString)), - None => return Err(self.peek_error(ErrorCode::EofWhileParsingObject)), - } - tri!(self.read.ignore_str()); - match tri!(self.parse_whitespace()) { - Some(b':') => self.eat_char(), - Some(_) => return Err(self.peek_error(ErrorCode::ExpectedColon)), - None => return Err(self.peek_error(ErrorCode::EofWhileParsingObject)), - } - } - - enclosing = Some(frame); - } - } - - fn ignore_integer(&mut self) -> Result<()> { - match tri!(self.next_char_or_null()) { - b'0' => { - // There can be only one leading '0'. - if let b'0'..=b'9' = tri!(self.peek_or_null()) { - return Err(self.peek_error(ErrorCode::InvalidNumber)); - } - } - b'1'..=b'9' => { - while let b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - } - } - _ => { - return Err(self.error(ErrorCode::InvalidNumber)); - } - } - - match tri!(self.peek_or_null()) { - b'.' => self.ignore_decimal(), - b'e' | b'E' => self.ignore_exponent(), - _ => Ok(()), - } - } - - fn ignore_decimal(&mut self) -> Result<()> { - self.eat_char(); - - let mut at_least_one_digit = false; - while let b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - at_least_one_digit = true; - } - - if !at_least_one_digit { - return Err(self.peek_error(ErrorCode::InvalidNumber)); - } - - match tri!(self.peek_or_null()) { - b'e' | b'E' => self.ignore_exponent(), - _ => Ok(()), - } - } - - fn ignore_exponent(&mut self) -> Result<()> { - self.eat_char(); - - match tri!(self.peek_or_null()) { - b'+' | b'-' => self.eat_char(), - _ => {} - } - - // Make sure a digit follows the exponent place. - match tri!(self.next_char_or_null()) { - b'0'..=b'9' => {} - _ => { - return Err(self.error(ErrorCode::InvalidNumber)); - } - } - - while let b'0'..=b'9' = tri!(self.peek_or_null()) { - self.eat_char(); - } - - Ok(()) - } - - #[cfg(feature = "raw_value")] - fn deserialize_raw_value<V>(&mut self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - tri!(self.parse_whitespace()); - self.read.begin_raw_buffering(); - tri!(self.ignore_value()); - self.read.end_raw_buffering(visitor) - } -} - -impl FromStr for Number { - type Err = Error; - - fn from_str(s: &str) -> result::Result<Self, Self::Err> { - Deserializer::from_str(s) - .parse_any_signed_number() - .map(Into::into) - } -} - -#[cfg(not(feature = "float_roundtrip"))] -static POW10: [f64; 309] = [ - 1e000, 1e001, 1e002, 1e003, 1e004, 1e005, 1e006, 1e007, 1e008, 1e009, // - 1e010, 1e011, 1e012, 1e013, 1e014, 1e015, 1e016, 1e017, 1e018, 1e019, // - 1e020, 1e021, 1e022, 1e023, 1e024, 1e025, 1e026, 1e027, 1e028, 1e029, // - 1e030, 1e031, 1e032, 1e033, 1e034, 1e035, 1e036, 1e037, 1e038, 1e039, // - 1e040, 1e041, 1e042, 1e043, 1e044, 1e045, 1e046, 1e047, 1e048, 1e049, // - 1e050, 1e051, 1e052, 1e053, 1e054, 1e055, 1e056, 1e057, 1e058, 1e059, // - 1e060, 1e061, 1e062, 1e063, 1e064, 1e065, 1e066, 1e067, 1e068, 1e069, // - 1e070, 1e071, 1e072, 1e073, 1e074, 1e075, 1e076, 1e077, 1e078, 1e079, // - 1e080, 1e081, 1e082, 1e083, 1e084, 1e085, 1e086, 1e087, 1e088, 1e089, // - 1e090, 1e091, 1e092, 1e093, 1e094, 1e095, 1e096, 1e097, 1e098, 1e099, // - 1e100, 1e101, 1e102, 1e103, 1e104, 1e105, 1e106, 1e107, 1e108, 1e109, // - 1e110, 1e111, 1e112, 1e113, 1e114, 1e115, 1e116, 1e117, 1e118, 1e119, // - 1e120, 1e121, 1e122, 1e123, 1e124, 1e125, 1e126, 1e127, 1e128, 1e129, // - 1e130, 1e131, 1e132, 1e133, 1e134, 1e135, 1e136, 1e137, 1e138, 1e139, // - 1e140, 1e141, 1e142, 1e143, 1e144, 1e145, 1e146, 1e147, 1e148, 1e149, // - 1e150, 1e151, 1e152, 1e153, 1e154, 1e155, 1e156, 1e157, 1e158, 1e159, // - 1e160, 1e161, 1e162, 1e163, 1e164, 1e165, 1e166, 1e167, 1e168, 1e169, // - 1e170, 1e171, 1e172, 1e173, 1e174, 1e175, 1e176, 1e177, 1e178, 1e179, // - 1e180, 1e181, 1e182, 1e183, 1e184, 1e185, 1e186, 1e187, 1e188, 1e189, // - 1e190, 1e191, 1e192, 1e193, 1e194, 1e195, 1e196, 1e197, 1e198, 1e199, // - 1e200, 1e201, 1e202, 1e203, 1e204, 1e205, 1e206, 1e207, 1e208, 1e209, // - 1e210, 1e211, 1e212, 1e213, 1e214, 1e215, 1e216, 1e217, 1e218, 1e219, // - 1e220, 1e221, 1e222, 1e223, 1e224, 1e225, 1e226, 1e227, 1e228, 1e229, // - 1e230, 1e231, 1e232, 1e233, 1e234, 1e235, 1e236, 1e237, 1e238, 1e239, // - 1e240, 1e241, 1e242, 1e243, 1e244, 1e245, 1e246, 1e247, 1e248, 1e249, // - 1e250, 1e251, 1e252, 1e253, 1e254, 1e255, 1e256, 1e257, 1e258, 1e259, // - 1e260, 1e261, 1e262, 1e263, 1e264, 1e265, 1e266, 1e267, 1e268, 1e269, // - 1e270, 1e271, 1e272, 1e273, 1e274, 1e275, 1e276, 1e277, 1e278, 1e279, // - 1e280, 1e281, 1e282, 1e283, 1e284, 1e285, 1e286, 1e287, 1e288, 1e289, // - 1e290, 1e291, 1e292, 1e293, 1e294, 1e295, 1e296, 1e297, 1e298, 1e299, // - 1e300, 1e301, 1e302, 1e303, 1e304, 1e305, 1e306, 1e307, 1e308, -]; - -macro_rules! deserialize_number { - ($method:ident) => { - deserialize_number!($method, deserialize_number); - }; - - ($method:ident, $using:ident) => { - fn $method<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.$using(visitor) - } - }; -} - -#[cfg(not(feature = "unbounded_depth"))] -macro_rules! if_checking_recursion_limit { - ($($body:tt)*) => { - $($body)* - }; -} - -#[cfg(feature = "unbounded_depth")] -macro_rules! if_checking_recursion_limit { - ($this:ident $($body:tt)*) => { - if !$this.disable_recursion_limit { - $this $($body)* - } - }; -} - -macro_rules! check_recursion { - ($this:ident $($body:tt)*) => { - if_checking_recursion_limit! { - $this.remaining_depth -= 1; - if $this.remaining_depth == 0 { - return Err($this.peek_error(ErrorCode::RecursionLimitExceeded)); - } - } - - $this $($body)* - - if_checking_recursion_limit! { - $this.remaining_depth += 1; - } - }; -} - -impl<'de, 'a, R: Read<'de>> de::Deserializer<'de> for &'a mut Deserializer<R> { - type Error = Error; - - #[inline] - fn deserialize_any<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'n' => { - self.eat_char(); - tri!(self.parse_ident(b"ull")); - visitor.visit_unit() - } - b't' => { - self.eat_char(); - tri!(self.parse_ident(b"rue")); - visitor.visit_bool(true) - } - b'f' => { - self.eat_char(); - tri!(self.parse_ident(b"alse")); - visitor.visit_bool(false) - } - b'-' => { - self.eat_char(); - tri!(self.parse_any_number(false)).visit(visitor) - } - b'0'..=b'9' => tri!(self.parse_any_number(true)).visit(visitor), - b'"' => { - self.eat_char(); - self.scratch.clear(); - match tri!(self.read.parse_str(&mut self.scratch)) { - Reference::Borrowed(s) => visitor.visit_borrowed_str(s), - Reference::Copied(s) => visitor.visit_str(s), - } - } - b'[' => { - check_recursion! { - self.eat_char(); - let ret = visitor.visit_seq(SeqAccess::new(self)); - } - - match (ret, self.end_seq()) { - (Ok(ret), Ok(())) => Ok(ret), - (Err(err), _) | (_, Err(err)) => Err(err), - } - } - b'{' => { - check_recursion! { - self.eat_char(); - let ret = visitor.visit_map(MapAccess::new(self)); - } - - match (ret, self.end_map()) { - (Ok(ret), Ok(())) => Ok(ret), - (Err(err), _) | (_, Err(err)) => Err(err), - } - } - _ => Err(self.peek_error(ErrorCode::ExpectedSomeValue)), - }; - - match value { - Ok(value) => Ok(value), - // The de::Error impl creates errors with unknown line and column. - // Fill in the position here by looking at the current index in the - // input. There is no way to tell whether this should call `error` - // or `peek_error` so pick the one that seems correct more often. - // Worst case, the position is off by one character. - Err(err) => Err(self.fix_position(err)), - } - } - - fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b't' => { - self.eat_char(); - tri!(self.parse_ident(b"rue")); - visitor.visit_bool(true) - } - b'f' => { - self.eat_char(); - tri!(self.parse_ident(b"alse")); - visitor.visit_bool(false) - } - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - deserialize_number!(deserialize_i8); - deserialize_number!(deserialize_i16); - deserialize_number!(deserialize_i32); - deserialize_number!(deserialize_i64); - deserialize_number!(deserialize_u8); - deserialize_number!(deserialize_u16); - deserialize_number!(deserialize_u32); - deserialize_number!(deserialize_u64); - #[cfg(not(feature = "float_roundtrip"))] - deserialize_number!(deserialize_f32); - deserialize_number!(deserialize_f64); - - #[cfg(feature = "float_roundtrip")] - deserialize_number!(deserialize_f32, do_deserialize_f32); - deserialize_number!(deserialize_i128, do_deserialize_i128); - deserialize_number!(deserialize_u128, do_deserialize_u128); - - fn deserialize_char<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_str(visitor) - } - - fn deserialize_str<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'"' => { - self.eat_char(); - self.scratch.clear(); - match tri!(self.read.parse_str(&mut self.scratch)) { - Reference::Borrowed(s) => visitor.visit_borrowed_str(s), - Reference::Copied(s) => visitor.visit_str(s), - } - } - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - fn deserialize_string<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_str(visitor) - } - - /// Parses a JSON string as bytes. Note that this function does not check - /// whether the bytes represent a valid UTF-8 string. - /// - /// The relevant part of the JSON specification is Section 8.2 of [RFC - /// 7159]: - /// - /// > When all the strings represented in a JSON text are composed entirely - /// > of Unicode characters (however escaped), then that JSON text is - /// > interoperable in the sense that all software implementations that - /// > parse it will agree on the contents of names and of string values in - /// > objects and arrays. - /// > - /// > However, the ABNF in this specification allows member names and string - /// > values to contain bit sequences that cannot encode Unicode characters; - /// > for example, "\uDEAD" (a single unpaired UTF-16 surrogate). Instances - /// > of this have been observed, for example, when a library truncates a - /// > UTF-16 string without checking whether the truncation split a - /// > surrogate pair. The behavior of software that receives JSON texts - /// > containing such values is unpredictable; for example, implementations - /// > might return different values for the length of a string value or even - /// > suffer fatal runtime exceptions. - /// - /// [RFC 7159]: https://tools.ietf.org/html/rfc7159 - /// - /// The behavior of serde_json is specified to fail on non-UTF-8 strings - /// when deserializing into Rust UTF-8 string types such as String, and - /// succeed with non-UTF-8 bytes when deserializing using this method. - /// - /// Escape sequences are processed as usual, and for `\uXXXX` escapes it is - /// still checked if the hex number represents a valid Unicode code point. - /// - /// # Examples - /// - /// You can use this to parse JSON strings containing invalid UTF-8 bytes, - /// or unpaired surrogates. - /// - /// ``` - /// use serde_bytes::ByteBuf; - /// - /// fn look_at_bytes() -> Result<(), serde_json::Error> { - /// let json_data = b"\"some bytes: \xe5\x00\xe5\""; - /// let bytes: ByteBuf = serde_json::from_slice(json_data)?; - /// - /// assert_eq!(b'\xe5', bytes[12]); - /// assert_eq!(b'\0', bytes[13]); - /// assert_eq!(b'\xe5', bytes[14]); - /// - /// Ok(()) - /// } - /// # - /// # look_at_bytes().unwrap(); - /// ``` - /// - /// Backslash escape sequences like `\n` are still interpreted and required - /// to be valid. `\u` escape sequences are required to represent a valid - /// Unicode code point or lone surrogate. - /// - /// ``` - /// use serde_bytes::ByteBuf; - /// - /// fn look_at_bytes() -> Result<(), serde_json::Error> { - /// let json_data = b"\"lone surrogate: \\uD801\""; - /// let bytes: ByteBuf = serde_json::from_slice(json_data)?; - /// let expected = b"lone surrogate: \xED\xA0\x81"; - /// assert_eq!(expected, bytes.as_slice()); - /// Ok(()) - /// } - /// # - /// # look_at_bytes(); - /// ``` - fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'"' => { - self.eat_char(); - self.scratch.clear(); - match tri!(self.read.parse_str_raw(&mut self.scratch)) { - Reference::Borrowed(b) => visitor.visit_borrowed_bytes(b), - Reference::Copied(b) => visitor.visit_bytes(b), - } - } - b'[' => self.deserialize_seq(visitor), - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - #[inline] - fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_bytes(visitor) - } - - /// Parses a `null` as a None, and any other values as a `Some(...)`. - #[inline] - fn deserialize_option<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - match tri!(self.parse_whitespace()) { - Some(b'n') => { - self.eat_char(); - tri!(self.parse_ident(b"ull")); - visitor.visit_none() - } - _ => visitor.visit_some(self), - } - } - - fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'n' => { - self.eat_char(); - tri!(self.parse_ident(b"ull")); - visitor.visit_unit() - } - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - fn deserialize_unit_struct<V>(self, _name: &'static str, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_unit(visitor) - } - - /// Parses a newtype struct as the underlying value. - #[inline] - fn deserialize_newtype_struct<V>(self, name: &str, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - #[cfg(feature = "raw_value")] - { - if name == crate::raw::TOKEN { - return self.deserialize_raw_value(visitor); - } - } - - let _ = name; - visitor.visit_newtype_struct(self) - } - - fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'[' => { - check_recursion! { - self.eat_char(); - let ret = visitor.visit_seq(SeqAccess::new(self)); - } - - match (ret, self.end_seq()) { - (Ok(ret), Ok(())) => Ok(ret), - (Err(err), _) | (_, Err(err)) => Err(err), - } - } - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - fn deserialize_tuple<V>(self, _len: usize, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_seq(visitor) - } - - fn deserialize_tuple_struct<V>( - self, - _name: &'static str, - _len: usize, - visitor: V, - ) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_seq(visitor) - } - - fn deserialize_map<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'{' => { - check_recursion! { - self.eat_char(); - let ret = visitor.visit_map(MapAccess::new(self)); - } - - match (ret, self.end_map()) { - (Ok(ret), Ok(())) => Ok(ret), - (Err(err), _) | (_, Err(err)) => Err(err), - } - } - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - fn deserialize_struct<V>( - self, - _name: &'static str, - _fields: &'static [&'static str], - visitor: V, - ) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - let peek = match tri!(self.parse_whitespace()) { - Some(b) => b, - None => { - return Err(self.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b'[' => { - check_recursion! { - self.eat_char(); - let ret = visitor.visit_seq(SeqAccess::new(self)); - } - - match (ret, self.end_seq()) { - (Ok(ret), Ok(())) => Ok(ret), - (Err(err), _) | (_, Err(err)) => Err(err), - } - } - b'{' => { - check_recursion! { - self.eat_char(); - let ret = visitor.visit_map(MapAccess::new(self)); - } - - match (ret, self.end_map()) { - (Ok(ret), Ok(())) => Ok(ret), - (Err(err), _) | (_, Err(err)) => Err(err), - } - } - _ => Err(self.peek_invalid_type(&visitor)), - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.fix_position(err)), - } - } - - /// Parses an enum as an object like `{"$KEY":$VALUE}`, where $VALUE is either a straight - /// value, a `[..]`, or a `{..}`. - #[inline] - fn deserialize_enum<V>( - self, - _name: &str, - _variants: &'static [&'static str], - visitor: V, - ) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - match tri!(self.parse_whitespace()) { - Some(b'{') => { - check_recursion! { - self.eat_char(); - let value = tri!(visitor.visit_enum(VariantAccess::new(self))); - } - - match tri!(self.parse_whitespace()) { - Some(b'}') => { - self.eat_char(); - Ok(value) - } - Some(_) => Err(self.error(ErrorCode::ExpectedSomeValue)), - None => Err(self.error(ErrorCode::EofWhileParsingObject)), - } - } - Some(b'"') => visitor.visit_enum(UnitVariantAccess::new(self)), - Some(_) => Err(self.peek_error(ErrorCode::ExpectedSomeValue)), - None => Err(self.peek_error(ErrorCode::EofWhileParsingValue)), - } - } - - fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_str(visitor) - } - - fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - tri!(self.ignore_value()); - visitor.visit_unit() - } -} - -struct SeqAccess<'a, R: 'a> { - de: &'a mut Deserializer<R>, - first: bool, -} - -impl<'a, R: 'a> SeqAccess<'a, R> { - fn new(de: &'a mut Deserializer<R>) -> Self { - SeqAccess { de, first: true } - } -} - -impl<'de, 'a, R: Read<'de> + 'a> de::SeqAccess<'de> for SeqAccess<'a, R> { - type Error = Error; - - fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>> - where - T: de::DeserializeSeed<'de>, - { - let peek = match tri!(self.de.parse_whitespace()) { - Some(b']') => { - return Ok(None); - } - Some(b',') if !self.first => { - self.de.eat_char(); - tri!(self.de.parse_whitespace()) - } - Some(b) => { - if self.first { - self.first = false; - Some(b) - } else { - return Err(self.de.peek_error(ErrorCode::ExpectedListCommaOrEnd)); - } - } - None => { - return Err(self.de.peek_error(ErrorCode::EofWhileParsingList)); - } - }; - - match peek { - Some(b']') => Err(self.de.peek_error(ErrorCode::TrailingComma)), - Some(_) => Ok(Some(tri!(seed.deserialize(&mut *self.de)))), - None => Err(self.de.peek_error(ErrorCode::EofWhileParsingValue)), - } - } -} - -struct MapAccess<'a, R: 'a> { - de: &'a mut Deserializer<R>, - first: bool, -} - -impl<'a, R: 'a> MapAccess<'a, R> { - fn new(de: &'a mut Deserializer<R>) -> Self { - MapAccess { de, first: true } - } -} - -impl<'de, 'a, R: Read<'de> + 'a> de::MapAccess<'de> for MapAccess<'a, R> { - type Error = Error; - - fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>> - where - K: de::DeserializeSeed<'de>, - { - let peek = match tri!(self.de.parse_whitespace()) { - Some(b'}') => { - return Ok(None); - } - Some(b',') if !self.first => { - self.de.eat_char(); - tri!(self.de.parse_whitespace()) - } - Some(b) => { - if self.first { - self.first = false; - Some(b) - } else { - return Err(self.de.peek_error(ErrorCode::ExpectedObjectCommaOrEnd)); - } - } - None => { - return Err(self.de.peek_error(ErrorCode::EofWhileParsingObject)); - } - }; - - match peek { - Some(b'"') => seed.deserialize(MapKey { de: &mut *self.de }).map(Some), - Some(b'}') => Err(self.de.peek_error(ErrorCode::TrailingComma)), - Some(_) => Err(self.de.peek_error(ErrorCode::KeyMustBeAString)), - None => Err(self.de.peek_error(ErrorCode::EofWhileParsingValue)), - } - } - - fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value> - where - V: de::DeserializeSeed<'de>, - { - tri!(self.de.parse_object_colon()); - - seed.deserialize(&mut *self.de) - } -} - -struct VariantAccess<'a, R: 'a> { - de: &'a mut Deserializer<R>, -} - -impl<'a, R: 'a> VariantAccess<'a, R> { - fn new(de: &'a mut Deserializer<R>) -> Self { - VariantAccess { de } - } -} - -impl<'de, 'a, R: Read<'de> + 'a> de::EnumAccess<'de> for VariantAccess<'a, R> { - type Error = Error; - type Variant = Self; - - fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self)> - where - V: de::DeserializeSeed<'de>, - { - let val = tri!(seed.deserialize(&mut *self.de)); - tri!(self.de.parse_object_colon()); - Ok((val, self)) - } -} - -impl<'de, 'a, R: Read<'de> + 'a> de::VariantAccess<'de> for VariantAccess<'a, R> { - type Error = Error; - - fn unit_variant(self) -> Result<()> { - de::Deserialize::deserialize(self.de) - } - - fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value> - where - T: de::DeserializeSeed<'de>, - { - seed.deserialize(self.de) - } - - fn tuple_variant<V>(self, _len: usize, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - de::Deserializer::deserialize_seq(self.de, visitor) - } - - fn struct_variant<V>(self, fields: &'static [&'static str], visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - de::Deserializer::deserialize_struct(self.de, "", fields, visitor) - } -} - -struct UnitVariantAccess<'a, R: 'a> { - de: &'a mut Deserializer<R>, -} - -impl<'a, R: 'a> UnitVariantAccess<'a, R> { - fn new(de: &'a mut Deserializer<R>) -> Self { - UnitVariantAccess { de } - } -} - -impl<'de, 'a, R: Read<'de> + 'a> de::EnumAccess<'de> for UnitVariantAccess<'a, R> { - type Error = Error; - type Variant = Self; - - fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self)> - where - V: de::DeserializeSeed<'de>, - { - let variant = tri!(seed.deserialize(&mut *self.de)); - Ok((variant, self)) - } -} - -impl<'de, 'a, R: Read<'de> + 'a> de::VariantAccess<'de> for UnitVariantAccess<'a, R> { - type Error = Error; - - fn unit_variant(self) -> Result<()> { - Ok(()) - } - - fn newtype_variant_seed<T>(self, _seed: T) -> Result<T::Value> - where - T: de::DeserializeSeed<'de>, - { - Err(de::Error::invalid_type( - Unexpected::UnitVariant, - &"newtype variant", - )) - } - - fn tuple_variant<V>(self, _len: usize, _visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - Err(de::Error::invalid_type( - Unexpected::UnitVariant, - &"tuple variant", - )) - } - - fn struct_variant<V>(self, _fields: &'static [&'static str], _visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - Err(de::Error::invalid_type( - Unexpected::UnitVariant, - &"struct variant", - )) - } -} - -/// Only deserialize from this after peeking a '"' byte! Otherwise it may -/// deserialize invalid JSON successfully. -struct MapKey<'a, R: 'a> { - de: &'a mut Deserializer<R>, -} - -macro_rules! deserialize_numeric_key { - ($method:ident) => { - fn $method<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.deserialize_number(visitor) - } - }; - - ($method:ident, $delegate:ident) => { - fn $method<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.de.eat_char(); - - match tri!(self.de.peek()) { - Some(b'0'..=b'9' | b'-') => {} - _ => return Err(self.de.error(ErrorCode::ExpectedNumericKey)), - } - - let value = tri!(self.de.$delegate(visitor)); - - match tri!(self.de.peek()) { - Some(b'"') => self.de.eat_char(), - _ => return Err(self.de.peek_error(ErrorCode::ExpectedDoubleQuote)), - } - - Ok(value) - } - }; -} - -impl<'de, 'a, R> MapKey<'a, R> -where - R: Read<'de>, -{ - deserialize_numeric_key!(deserialize_number, deserialize_number); -} - -impl<'de, 'a, R> de::Deserializer<'de> for MapKey<'a, R> -where - R: Read<'de>, -{ - type Error = Error; - - #[inline] - fn deserialize_any<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.de.eat_char(); - self.de.scratch.clear(); - match tri!(self.de.read.parse_str(&mut self.de.scratch)) { - Reference::Borrowed(s) => visitor.visit_borrowed_str(s), - Reference::Copied(s) => visitor.visit_str(s), - } - } - - deserialize_numeric_key!(deserialize_i8); - deserialize_numeric_key!(deserialize_i16); - deserialize_numeric_key!(deserialize_i32); - deserialize_numeric_key!(deserialize_i64); - deserialize_numeric_key!(deserialize_i128, deserialize_i128); - deserialize_numeric_key!(deserialize_u8); - deserialize_numeric_key!(deserialize_u16); - deserialize_numeric_key!(deserialize_u32); - deserialize_numeric_key!(deserialize_u64); - deserialize_numeric_key!(deserialize_u128, deserialize_u128); - #[cfg(not(feature = "float_roundtrip"))] - deserialize_numeric_key!(deserialize_f32); - #[cfg(feature = "float_roundtrip")] - deserialize_numeric_key!(deserialize_f32, deserialize_f32); - deserialize_numeric_key!(deserialize_f64); - - fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.de.eat_char(); - - let peek = match tri!(self.de.next_char()) { - Some(b) => b, - None => { - return Err(self.de.peek_error(ErrorCode::EofWhileParsingValue)); - } - }; - - let value = match peek { - b't' => { - tri!(self.de.parse_ident(b"rue\"")); - visitor.visit_bool(true) - } - b'f' => { - tri!(self.de.parse_ident(b"alse\"")); - visitor.visit_bool(false) - } - _ => { - self.de.scratch.clear(); - let s = tri!(self.de.read.parse_str(&mut self.de.scratch)); - Err(de::Error::invalid_type(Unexpected::Str(&s), &visitor)) - } - }; - - match value { - Ok(value) => Ok(value), - Err(err) => Err(self.de.fix_position(err)), - } - } - - #[inline] - fn deserialize_option<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - // Map keys cannot be null. - visitor.visit_some(self) - } - - #[inline] - fn deserialize_newtype_struct<V>(self, name: &'static str, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - #[cfg(feature = "raw_value")] - { - if name == crate::raw::TOKEN { - return self.de.deserialize_raw_value(visitor); - } - } - - let _ = name; - visitor.visit_newtype_struct(self) - } - - #[inline] - fn deserialize_enum<V>( - self, - name: &'static str, - variants: &'static [&'static str], - visitor: V, - ) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.de.deserialize_enum(name, variants, visitor) - } - - #[inline] - fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.de.deserialize_bytes(visitor) - } - - #[inline] - fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value> - where - V: de::Visitor<'de>, - { - self.de.deserialize_bytes(visitor) - } - - forward_to_deserialize_any! { - char str string unit unit_struct seq tuple tuple_struct map struct - identifier ignored_any - } -} - -////////////////////////////////////////////////////////////////////////////// - -/// Iterator that deserializes a stream into multiple JSON values. -/// -/// A stream deserializer can be created from any JSON deserializer using the -/// `Deserializer::into_iter` method. -/// -/// The data can consist of any JSON value. Values need to be a self-delineating value e.g. -/// arrays, objects, or strings, or be followed by whitespace or a self-delineating value. -/// -/// ``` -/// use serde_json::{Deserializer, Value}; -/// -/// fn main() { -/// let data = "{\"k\": 3}1\"cool\"\"stuff\" 3{} [0, 1, 2]"; -/// -/// let stream = Deserializer::from_str(data).into_iter::<Value>(); -/// -/// for value in stream { -/// println!("{}", value.unwrap()); -/// } -/// } -/// ``` -pub struct StreamDeserializer<'de, R, T> { - de: Deserializer<R>, - offset: usize, - failed: bool, - output: PhantomData<T>, - lifetime: PhantomData<&'de ()>, -} - -impl<'de, R, T> StreamDeserializer<'de, R, T> -where - R: read::Read<'de>, - T: de::Deserialize<'de>, -{ - /// Create a JSON stream deserializer from one of the possible serde_json - /// input sources. - /// - /// Typically it is more convenient to use one of these methods instead: - /// - /// - Deserializer::from_str(...).into_iter() - /// - Deserializer::from_slice(...).into_iter() - /// - Deserializer::from_reader(...).into_iter() - pub fn new(read: R) -> Self { - let offset = read.byte_offset(); - StreamDeserializer { - de: Deserializer::new(read), - offset, - failed: false, - output: PhantomData, - lifetime: PhantomData, - } - } - - /// Returns the number of bytes so far deserialized into a successful `T`. - /// - /// If a stream deserializer returns an EOF error, new data can be joined to - /// `old_data[stream.byte_offset()..]` to try again. - /// - /// ``` - /// let data = b"[0] [1] ["; - /// - /// let de = serde_json::Deserializer::from_slice(data); - /// let mut stream = de.into_iter::<Vec<i32>>(); - /// assert_eq!(0, stream.byte_offset()); - /// - /// println!("{:?}", stream.next()); // [0] - /// assert_eq!(3, stream.byte_offset()); - /// - /// println!("{:?}", stream.next()); // [1] - /// assert_eq!(7, stream.byte_offset()); - /// - /// println!("{:?}", stream.next()); // error - /// assert_eq!(8, stream.byte_offset()); - /// - /// // If err.is_eof(), can join the remaining data to new data and continue. - /// let remaining = &data[stream.byte_offset()..]; - /// ``` - /// - /// *Note:* In the future this method may be changed to return the number of - /// bytes so far deserialized into a successful T *or* syntactically valid - /// JSON skipped over due to a type error. See [serde-rs/json#70] for an - /// example illustrating this. - /// - /// [serde-rs/json#70]: https://github.com/serde-rs/json/issues/70 - pub fn byte_offset(&self) -> usize { - self.offset - } - - fn peek_end_of_value(&mut self) -> Result<()> { - match tri!(self.de.peek()) { - Some(b' ' | b'\n' | b'\t' | b'\r' | b'"' | b'[' | b']' | b'{' | b'}' | b',' | b':') - | None => Ok(()), - Some(_) => { - let position = self.de.read.peek_position(); - Err(Error::syntax( - ErrorCode::TrailingCharacters, - position.line, - position.column, - )) - } - } - } -} - -impl<'de, R, T> Iterator for StreamDeserializer<'de, R, T> -where - R: Read<'de>, - T: de::Deserialize<'de>, -{ - type Item = Result<T>; - - fn next(&mut self) -> Option<Result<T>> { - if R::should_early_return_if_failed && self.failed { - return None; - } - - // skip whitespaces, if any - // this helps with trailing whitespaces, since whitespaces between - // values are handled for us. - match self.de.parse_whitespace() { - Ok(None) => { - self.offset = self.de.read.byte_offset(); - None - } - Ok(Some(b)) => { - // If the value does not have a clear way to show the end of the value - // (like numbers, null, true etc.) we have to look for whitespace or - // the beginning of a self-delineated value. - let self_delineated_value = match b { - b'[' | b'"' | b'{' => true, - _ => false, - }; - self.offset = self.de.read.byte_offset(); - let result = de::Deserialize::deserialize(&mut self.de); - - Some(match result { - Ok(value) => { - self.offset = self.de.read.byte_offset(); - if self_delineated_value { - Ok(value) - } else { - self.peek_end_of_value().map(|()| value) - } - } - Err(e) => { - self.de.read.set_failed(&mut self.failed); - Err(e) - } - }) - } - Err(e) => { - self.de.read.set_failed(&mut self.failed); - Some(Err(e)) - } - } - } -} - -impl<'de, R, T> FusedIterator for StreamDeserializer<'de, R, T> -where - R: Read<'de> + Fused, - T: de::Deserialize<'de>, -{ -} - -////////////////////////////////////////////////////////////////////////////// - -fn from_trait<'de, R, T>(read: R) -> Result<T> -where - R: Read<'de>, - T: de::Deserialize<'de>, -{ - let mut de = Deserializer::new(read); - let value = tri!(de::Deserialize::deserialize(&mut de)); - - // Make sure the whole stream has been consumed. - tri!(de.end()); - Ok(value) -} - -/// Deserialize an instance of type `T` from an I/O stream of JSON. -/// -/// The content of the I/O stream is deserialized directly from the stream -/// without being buffered in memory by serde_json. -/// -/// When reading from a source against which short reads are not efficient, such -/// as a [`File`], you will want to apply your own buffering because serde_json -/// will not buffer the input. See [`std::io::BufReader`]. -/// -/// It is expected that the input stream ends after the deserialized object. -/// If the stream does not end, such as in the case of a persistent socket connection, -/// this function will not return. It is possible instead to deserialize from a prefix of an input -/// stream without looking for EOF by managing your own [`Deserializer`]. -/// -/// Note that counter to intuition, this function is usually slower than -/// reading a file completely into memory and then applying [`from_str`] -/// or [`from_slice`] on it. See [issue #160]. -/// -/// [`File`]: https://doc.rust-lang.org/std/fs/struct.File.html -/// [`std::io::BufReader`]: https://doc.rust-lang.org/std/io/struct.BufReader.html -/// [`from_str`]: ./fn.from_str.html -/// [`from_slice`]: ./fn.from_slice.html -/// [issue #160]: https://github.com/serde-rs/json/issues/160 -/// -/// # Example -/// -/// Reading the contents of a file. -/// -/// ``` -/// use serde::Deserialize; -/// -/// use std::error::Error; -/// use std::fs::File; -/// use std::io::BufReader; -/// use std::path::Path; -/// -/// #[derive(Deserialize, Debug)] -/// struct User { -/// fingerprint: String, -/// location: String, -/// } -/// -/// fn read_user_from_file<P: AsRef<Path>>(path: P) -> Result<User, Box<dyn Error>> { -/// // Open the file in read-only mode with buffer. -/// let file = File::open(path)?; -/// let reader = BufReader::new(file); -/// -/// // Read the JSON contents of the file as an instance of `User`. -/// let u = serde_json::from_reader(reader)?; -/// -/// // Return the `User`. -/// Ok(u) -/// } -/// -/// fn main() { -/// # } -/// # fn fake_main() { -/// let u = read_user_from_file("test.json").unwrap(); -/// println!("{:#?}", u); -/// } -/// ``` -/// -/// Reading from a persistent socket connection. -/// -/// ``` -/// use serde::Deserialize; -/// -/// use std::error::Error; -/// use std::net::{TcpListener, TcpStream}; -/// -/// #[derive(Deserialize, Debug)] -/// struct User { -/// fingerprint: String, -/// location: String, -/// } -/// -/// fn read_user_from_stream(tcp_stream: TcpStream) -> Result<User, Box<dyn Error>> { -/// let mut de = serde_json::Deserializer::from_reader(tcp_stream); -/// let u = User::deserialize(&mut de)?; -/// -/// Ok(u) -/// } -/// -/// fn main() { -/// # } -/// # fn fake_main() { -/// let listener = TcpListener::bind("127.0.0.1:4000").unwrap(); -/// -/// for stream in listener.incoming() { -/// println!("{:#?}", read_user_from_stream(stream.unwrap())); -/// } -/// } -/// ``` -/// -/// # Errors -/// -/// This conversion can fail if the structure of the input does not match the -/// structure expected by `T`, for example if `T` is a struct type but the input -/// contains something other than a JSON map. It can also fail if the structure -/// is correct but `T`'s implementation of `Deserialize` decides that something -/// is wrong with the data, for example required struct fields are missing from -/// the JSON map or some number is too big to fit in the expected primitive -/// type. -#[cfg(feature = "std")] -#[cfg_attr(docsrs, doc(cfg(feature = "std")))] -pub fn from_reader<R, T>(rdr: R) -> Result<T> -where - R: crate::io::Read, - T: de::DeserializeOwned, -{ - from_trait(read::IoRead::new(rdr)) -} - -/// Deserialize an instance of type `T` from bytes of JSON text. -/// -/// # Example -/// -/// ``` -/// use serde::Deserialize; -/// -/// #[derive(Deserialize, Debug)] -/// struct User { -/// fingerprint: String, -/// location: String, -/// } -/// -/// fn main() { -/// // The type of `j` is `&[u8]` -/// let j = b" -/// { -/// \"fingerprint\": \"0xF9BA143B95FF6D82\", -/// \"location\": \"Menlo Park, CA\" -/// }"; -/// -/// let u: User = serde_json::from_slice(j).unwrap(); -/// println!("{:#?}", u); -/// } -/// ``` -/// -/// # Errors -/// -/// This conversion can fail if the structure of the input does not match the -/// structure expected by `T`, for example if `T` is a struct type but the input -/// contains something other than a JSON map. It can also fail if the structure -/// is correct but `T`'s implementation of `Deserialize` decides that something -/// is wrong with the data, for example required struct fields are missing from -/// the JSON map or some number is too big to fit in the expected primitive -/// type. -pub fn from_slice<'a, T>(v: &'a [u8]) -> Result<T> -where - T: de::Deserialize<'a>, -{ - from_trait(read::SliceRead::new(v)) -} - -/// Deserialize an instance of type `T` from a string of JSON text. -/// -/// # Example -/// -/// ``` -/// use serde::Deserialize; -/// -/// #[derive(Deserialize, Debug)] -/// struct User { -/// fingerprint: String, -/// location: String, -/// } -/// -/// fn main() { -/// // The type of `j` is `&str` -/// let j = " -/// { -/// \"fingerprint\": \"0xF9BA143B95FF6D82\", -/// \"location\": \"Menlo Park, CA\" -/// }"; -/// -/// let u: User = serde_json::from_str(j).unwrap(); -/// println!("{:#?}", u); -/// } -/// ``` -/// -/// # Errors -/// -/// This conversion can fail if the structure of the input does not match the -/// structure expected by `T`, for example if `T` is a struct type but the input -/// contains something other than a JSON map. It can also fail if the structure -/// is correct but `T`'s implementation of `Deserialize` decides that something -/// is wrong with the data, for example required struct fields are missing from -/// the JSON map or some number is too big to fit in the expected primitive -/// type. -pub fn from_str<'a, T>(s: &'a str) -> Result<T> -where - T: de::Deserialize<'a>, -{ - from_trait(read::StrRead::new(s)) -} |