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android / platform / external / rust / crates / serde / 6aca21bfa0430125b34b388a26a22e5ee6952206 / . / src / de / impls.rs
blob: a257d9e2f4f101b8d90e00681f7f2b3c68749781 [file] [log] [blame]
use lib::*;
use de::{
Deserialize, Deserializer, EnumAccess, Error, SeqAccess, Unexpected, VariantAccess, Visitor,
};
#[cfg(any(feature = "std", feature = "alloc", not(no_core_duration)))]
use de::MapAccess;
use seed::InPlaceSeed;
#[cfg(any(feature = "std", feature = "alloc"))]
use __private::size_hint;
////////////////////////////////////////////////////////////////////////////////
struct UnitVisitor;
impl<'de> Visitor<'de> for UnitVisitor {
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("unit")
}
fn visit_unit<E>(self) -> Result<Self::Value, E>
where
E: Error,
{
Ok(())
}
}
impl<'de> Deserialize<'de> for () {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_unit(UnitVisitor)
}
}
#[cfg(feature = "unstable")]
impl<'de> Deserialize<'de> for ! {
fn deserialize<D>(_deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
Err(Error::custom("cannot deserialize `!`"))
}
}
////////////////////////////////////////////////////////////////////////////////
struct BoolVisitor;
impl<'de> Visitor<'de> for BoolVisitor {
type Value = bool;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a boolean")
}
fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v)
}
}
impl<'de> Deserialize<'de> for bool {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_bool(BoolVisitor)
}
}
////////////////////////////////////////////////////////////////////////////////
macro_rules! impl_deserialize_num {
($primitive:ident, $nonzero:ident $(cfg($($cfg:tt)*))*, $deserialize:ident $($method:ident!($($val:ident : $visit:ident)*);)*) => {
impl_deserialize_num!($primitive, $deserialize $($method!($($val : $visit)*);)*);
#[cfg(all(not(no_num_nonzero), $($($cfg)*)*))]
impl<'de> Deserialize<'de> for num::$nonzero {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct NonZeroVisitor;
impl<'de> Visitor<'de> for NonZeroVisitor {
type Value = num::$nonzero;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(concat!("a nonzero ", stringify!($primitive)))
}
$($($method!(nonzero $primitive $val : $visit);)*)*
}
deserializer.$deserialize(NonZeroVisitor)
}
}
};
($primitive:ident, $deserialize:ident $($method:ident!($($val:ident : $visit:ident)*);)*) => {
impl<'de> Deserialize<'de> for $primitive {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct PrimitiveVisitor;
impl<'de> Visitor<'de> for PrimitiveVisitor {
type Value = $primitive;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(stringify!($primitive))
}
$($($method!($val : $visit);)*)*
}
deserializer.$deserialize(PrimitiveVisitor)
}
}
};
}
macro_rules! num_self {
($ty:ident : $visit:ident) => {
#[inline]
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v)
}
};
(nonzero $primitive:ident $ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if let Some(nonzero) = Self::Value::new(v) {
Ok(nonzero)
} else {
Err(Error::invalid_value(Unexpected::Unsigned(0), &self))
}
}
};
}
macro_rules! num_as_self {
($ty:ident : $visit:ident) => {
#[inline]
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v as Self::Value)
}
};
(nonzero $primitive:ident $ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if let Some(nonzero) = Self::Value::new(v as $primitive) {
Ok(nonzero)
} else {
Err(Error::invalid_value(Unexpected::Unsigned(0), &self))
}
}
};
}
macro_rules! int_to_int {
($ty:ident : $visit:ident) => {
#[inline]
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if Self::Value::min_value() as i64 <= v as i64
&& v as i64 <= Self::Value::max_value() as i64
{
Ok(v as Self::Value)
} else {
Err(Error::invalid_value(Unexpected::Signed(v as i64), &self))
}
}
};
(nonzero $primitive:ident $ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if $primitive::min_value() as i64 <= v as i64
&& v as i64 <= $primitive::max_value() as i64
{
if let Some(nonzero) = Self::Value::new(v as $primitive) {
return Ok(nonzero);
}
}
Err(Error::invalid_value(Unexpected::Signed(v as i64), &self))
}
};
}
macro_rules! int_to_uint {
($ty:ident : $visit:ident) => {
#[inline]
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if 0 <= v && v as u64 <= Self::Value::max_value() as u64 {
Ok(v as Self::Value)
} else {
Err(Error::invalid_value(Unexpected::Signed(v as i64), &self))
}
}
};
(nonzero $primitive:ident $ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if 0 < v && v as u64 <= $primitive::max_value() as u64 {
if let Some(nonzero) = Self::Value::new(v as $primitive) {
return Ok(nonzero);
}
}
Err(Error::invalid_value(Unexpected::Signed(v as i64), &self))
}
};
}
macro_rules! uint_to_self {
($ty:ident : $visit:ident) => {
#[inline]
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if v as u64 <= Self::Value::max_value() as u64 {
Ok(v as Self::Value)
} else {
Err(Error::invalid_value(Unexpected::Unsigned(v as u64), &self))
}
}
};
(nonzero $primitive:ident $ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if v as u64 <= $primitive::max_value() as u64 {
if let Some(nonzero) = Self::Value::new(v as $primitive) {
return Ok(nonzero);
}
}
Err(Error::invalid_value(Unexpected::Unsigned(v as u64), &self))
}
};
}
impl_deserialize_num! {
i8, NonZeroI8 cfg(not(no_num_nonzero_signed)), deserialize_i8
num_self!(i8:visit_i8);
int_to_int!(i16:visit_i16 i32:visit_i32 i64:visit_i64);
uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
i16, NonZeroI16 cfg(not(no_num_nonzero_signed)), deserialize_i16
num_self!(i16:visit_i16);
num_as_self!(i8:visit_i8);
int_to_int!(i32:visit_i32 i64:visit_i64);
uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
i32, NonZeroI32 cfg(not(no_num_nonzero_signed)), deserialize_i32
num_self!(i32:visit_i32);
num_as_self!(i8:visit_i8 i16:visit_i16);
int_to_int!(i64:visit_i64);
uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
i64, NonZeroI64 cfg(not(no_num_nonzero_signed)), deserialize_i64
num_self!(i64:visit_i64);
num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32);
uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
isize, NonZeroIsize cfg(not(no_num_nonzero_signed)), deserialize_i64
num_as_self!(i8:visit_i8 i16:visit_i16);
int_to_int!(i32:visit_i32 i64:visit_i64);
uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
u8, NonZeroU8, deserialize_u8
num_self!(u8:visit_u8);
int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
uint_to_self!(u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
u16, NonZeroU16, deserialize_u16
num_self!(u16:visit_u16);
num_as_self!(u8:visit_u8);
int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
uint_to_self!(u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
u32, NonZeroU32, deserialize_u32
num_self!(u32:visit_u32);
num_as_self!(u8:visit_u8 u16:visit_u16);
int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
uint_to_self!(u64:visit_u64);
}
impl_deserialize_num! {
u64, NonZeroU64, deserialize_u64
num_self!(u64:visit_u64);
num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32);
int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
}
impl_deserialize_num! {
usize, NonZeroUsize, deserialize_u64
num_as_self!(u8:visit_u8 u16:visit_u16);
int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
uint_to_self!(u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
f32, deserialize_f32
num_self!(f32:visit_f32);
num_as_self!(f64:visit_f64);
num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
impl_deserialize_num! {
f64, deserialize_f64
num_self!(f64:visit_f64);
num_as_self!(f32:visit_f32);
num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
}
serde_if_integer128! {
macro_rules! num_128 {
($ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if v as i128 >= Self::Value::min_value() as i128
&& v as u128 <= Self::Value::max_value() as u128
{
Ok(v as Self::Value)
} else {
Err(Error::invalid_value(
Unexpected::Other(stringify!($ty)),
&self,
))
}
}
};
(nonzero $primitive:ident $ty:ident : $visit:ident) => {
fn $visit<E>(self, v: $ty) -> Result<Self::Value, E>
where
E: Error,
{
if v as i128 >= $primitive::min_value() as i128
&& v as u128 <= $primitive::max_value() as u128
{
if let Some(nonzero) = Self::Value::new(v as $primitive) {
Ok(nonzero)
} else {
Err(Error::invalid_value(Unexpected::Unsigned(0), &self))
}
} else {
Err(Error::invalid_value(
Unexpected::Other(stringify!($ty)),
&self,
))
}
}
};
}
impl_deserialize_num! {
i128, NonZeroI128 cfg(not(no_num_nonzero_signed)), deserialize_i128
num_self!(i128:visit_i128);
num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
num_128!(u128:visit_u128);
}
impl_deserialize_num! {
u128, NonZeroU128, deserialize_u128
num_self!(u128:visit_u128);
num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64);
int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64);
num_128!(i128:visit_i128);
}
}
////////////////////////////////////////////////////////////////////////////////
struct CharVisitor;
impl<'de> Visitor<'de> for CharVisitor {
type Value = char;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a character")
}
#[inline]
fn visit_char<E>(self, v: char) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v)
}
#[inline]
fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
where
E: Error,
{
let mut iter = v.chars();
match (iter.next(), iter.next()) {
(Some(c), None) => Ok(c),
_ => Err(Error::invalid_value(Unexpected::Str(v), &self)),
}
}
}
impl<'de> Deserialize<'de> for char {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_char(CharVisitor)
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(any(feature = "std", feature = "alloc"))]
struct StringVisitor;
#[cfg(any(feature = "std", feature = "alloc"))]
struct StringInPlaceVisitor<'a>(&'a mut String);
#[cfg(any(feature = "std", feature = "alloc"))]
impl<'de> Visitor<'de> for StringVisitor {
type Value = String;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a string")
}
fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v.to_owned())
}
fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v)
}
fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match str::from_utf8(v) {
Ok(s) => Ok(s.to_owned()),
Err(_) => Err(Error::invalid_value(Unexpected::Bytes(v), &self)),
}
}
fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
where
E: Error,
{
match String::from_utf8(v) {
Ok(s) => Ok(s),
Err(e) => Err(Error::invalid_value(
Unexpected::Bytes(&e.into_bytes()),
&self,
)),
}
}
}
#[cfg(any(feature = "std", feature = "alloc"))]
impl<'a, 'de> Visitor<'de> for StringInPlaceVisitor<'a> {
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a string")
}
fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
where
E: Error,
{
self.0.clear();
self.0.push_str(v);
Ok(())
}
fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
where
E: Error,
{
*self.0 = v;
Ok(())
}
fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match str::from_utf8(v) {
Ok(s) => {
self.0.clear();
self.0.push_str(s);
Ok(())
}
Err(_) => Err(Error::invalid_value(Unexpected::Bytes(v), &self)),
}
}
fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
where
E: Error,
{
match String::from_utf8(v) {
Ok(s) => {
*self.0 = s;
Ok(())
}
Err(e) => Err(Error::invalid_value(
Unexpected::Bytes(&e.into_bytes()),
&self,
)),
}
}
}
#[cfg(any(feature = "std", feature = "alloc"))]
impl<'de> Deserialize<'de> for String {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_string(StringVisitor)
}
fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_string(StringInPlaceVisitor(place))
}
}
////////////////////////////////////////////////////////////////////////////////
struct StrVisitor;
impl<'a> Visitor<'a> for StrVisitor {
type Value = &'a str;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a borrowed string")
}
fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v) // so easy
}
fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E>
where
E: Error,
{
str::from_utf8(v).map_err(|_| Error::invalid_value(Unexpected::Bytes(v), &self))
}
}
impl<'de: 'a, 'a> Deserialize<'de> for &'a str {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_str(StrVisitor)
}
}
////////////////////////////////////////////////////////////////////////////////
struct BytesVisitor;
impl<'a> Visitor<'a> for BytesVisitor {
type Value = &'a [u8];
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a borrowed byte array")
}
fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v)
}
fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v.as_bytes())
}
}
impl<'de: 'a, 'a> Deserialize<'de> for &'a [u8] {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_bytes(BytesVisitor)
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(feature = "std")]
struct CStringVisitor;
#[cfg(feature = "std")]
impl<'de> Visitor<'de> for CStringVisitor {
type Value = CString;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("byte array")
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let len = size_hint::cautious(seq.size_hint());
let mut values = Vec::with_capacity(len);
while let Some(value) = try!(seq.next_element()) {
values.push(value);
}
CString::new(values).map_err(Error::custom)
}
fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
CString::new(v).map_err(Error::custom)
}
fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
where
E: Error,
{
CString::new(v).map_err(Error::custom)
}
fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
where
E: Error,
{
CString::new(v).map_err(Error::custom)
}
fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
where
E: Error,
{
CString::new(v).map_err(Error::custom)
}
}
#[cfg(feature = "std")]
impl<'de> Deserialize<'de> for CString {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_byte_buf(CStringVisitor)
}
}
macro_rules! forwarded_impl {
(
$(#[doc = $doc:tt])*
($($id:ident),*), $ty:ty, $func:expr
) => {
$(#[doc = $doc])*
impl<'de $(, $id : Deserialize<'de>,)*> Deserialize<'de> for $ty {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
Deserialize::deserialize(deserializer).map($func)
}
}
}
}
#[cfg(all(feature = "std", not(no_de_boxed_c_str)))]
forwarded_impl!((), Box<CStr>, CString::into_boxed_c_str);
#[cfg(not(no_core_reverse))]
forwarded_impl!((T), Reverse<T>, Reverse);
////////////////////////////////////////////////////////////////////////////////
struct OptionVisitor<T> {
marker: PhantomData<T>,
}
impl<'de, T> Visitor<'de> for OptionVisitor<T>
where
T: Deserialize<'de>,
{
type Value = Option<T>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("option")
}
#[inline]
fn visit_unit<E>(self) -> Result<Self::Value, E>
where
E: Error,
{
Ok(None)
}
#[inline]
fn visit_none<E>(self) -> Result<Self::Value, E>
where
E: Error,
{
Ok(None)
}
#[inline]
fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
where
D: Deserializer<'de>,
{
T::deserialize(deserializer).map(Some)
}
fn __private_visit_untagged_option<D>(self, deserializer: D) -> Result<Self::Value, ()>
where
D: Deserializer<'de>,
{
Ok(T::deserialize(deserializer).ok())
}
}
impl<'de, T> Deserialize<'de> for Option<T>
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_option(OptionVisitor {
marker: PhantomData,
})
}
// The Some variant's repr is opaque, so we can't play cute tricks with its
// tag to have deserialize_in_place build the content in place unconditionally.
//
// FIXME: investigate whether branching on the old value being Some to
// deserialize_in_place the value is profitable (probably data-dependent?)
}
////////////////////////////////////////////////////////////////////////////////
struct PhantomDataVisitor<T: ?Sized> {
marker: PhantomData<T>,
}
impl<'de, T: ?Sized> Visitor<'de> for PhantomDataVisitor<T> {
type Value = PhantomData<T>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("unit")
}
#[inline]
fn visit_unit<E>(self) -> Result<Self::Value, E>
where
E: Error,
{
Ok(PhantomData)
}
}
impl<'de, T: ?Sized> Deserialize<'de> for PhantomData<T> {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
let visitor = PhantomDataVisitor {
marker: PhantomData,
};
deserializer.deserialize_unit_struct("PhantomData", visitor)
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(any(feature = "std", feature = "alloc"))]
macro_rules! seq_impl {
(
$ty:ident <T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound1:ident $(+ $bound2:ident)*)*>,
$access:ident,
$clear:expr,
$with_capacity:expr,
$reserve:expr,
$insert:expr
) => {
impl<'de, T $(, $typaram)*> Deserialize<'de> for $ty<T $(, $typaram)*>
where
T: Deserialize<'de> $(+ $tbound1 $(+ $tbound2)*)*,
$($typaram: $bound1 $(+ $bound2)*,)*
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct SeqVisitor<T $(, $typaram)*> {
marker: PhantomData<$ty<T $(, $typaram)*>>,
}
impl<'de, T $(, $typaram)*> Visitor<'de> for SeqVisitor<T $(, $typaram)*>
where
T: Deserialize<'de> $(+ $tbound1 $(+ $tbound2)*)*,
$($typaram: $bound1 $(+ $bound2)*,)*
{
type Value = $ty<T $(, $typaram)*>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a sequence")
}
#[inline]
fn visit_seq<A>(self, mut $access: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let mut values = $with_capacity;
while let Some(value) = try!($access.next_element()) {
$insert(&mut values, value);
}
Ok(values)
}
}
let visitor = SeqVisitor { marker: PhantomData };
deserializer.deserialize_seq(visitor)
}
fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error>
where
D: Deserializer<'de>,
{
struct SeqInPlaceVisitor<'a, T: 'a $(, $typaram: 'a)*>(&'a mut $ty<T $(, $typaram)*>);
impl<'a, 'de, T $(, $typaram)*> Visitor<'de> for SeqInPlaceVisitor<'a, T $(, $typaram)*>
where
T: Deserialize<'de> $(+ $tbound1 $(+ $tbound2)*)*,
$($typaram: $bound1 $(+ $bound2)*,)*
{
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a sequence")
}
#[inline]
fn visit_seq<A>(mut self, mut $access: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
$clear(&mut self.0);
$reserve(&mut self.0, size_hint::cautious($access.size_hint()));
// FIXME: try to overwrite old values here? (Vec, VecDeque, LinkedList)
while let Some(value) = try!($access.next_element()) {
$insert(&mut self.0, value);
}
Ok(())
}
}
deserializer.deserialize_seq(SeqInPlaceVisitor(place))
}
}
}
}
// Dummy impl of reserve
#[cfg(any(feature = "std", feature = "alloc"))]
fn nop_reserve<T>(_seq: T, _n: usize) {}
#[cfg(any(feature = "std", feature = "alloc"))]
seq_impl!(
BinaryHeap<T: Ord>,
seq,
BinaryHeap::clear,
BinaryHeap::with_capacity(size_hint::cautious(seq.size_hint())),
BinaryHeap::reserve,
BinaryHeap::push
);
#[cfg(any(feature = "std", feature = "alloc"))]
seq_impl!(
BTreeSet<T: Eq + Ord>,
seq,
BTreeSet::clear,
BTreeSet::new(),
nop_reserve,
BTreeSet::insert
);
#[cfg(any(feature = "std", feature = "alloc"))]
seq_impl!(
LinkedList<T>,
seq,
LinkedList::clear,
LinkedList::new(),
nop_reserve,
LinkedList::push_back
);
#[cfg(feature = "std")]
seq_impl!(
HashSet<T: Eq + Hash, S: BuildHasher + Default>,
seq,
HashSet::clear,
HashSet::with_capacity_and_hasher(size_hint::cautious(seq.size_hint()), S::default()),
HashSet::reserve,
HashSet::insert);
#[cfg(any(feature = "std", feature = "alloc"))]
seq_impl!(
VecDeque<T>,
seq,
VecDeque::clear,
VecDeque::with_capacity(size_hint::cautious(seq.size_hint())),
VecDeque::reserve,
VecDeque::push_back
);
////////////////////////////////////////////////////////////////////////////////
#[cfg(any(feature = "std", feature = "alloc"))]
impl<'de, T> Deserialize<'de> for Vec<T>
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct VecVisitor<T> {
marker: PhantomData<T>,
}
impl<'de, T> Visitor<'de> for VecVisitor<T>
where
T: Deserialize<'de>,
{
type Value = Vec<T>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a sequence")
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let mut values = Vec::with_capacity(size_hint::cautious(seq.size_hint()));
while let Some(value) = try!(seq.next_element()) {
values.push(value);
}
Ok(values)
}
}
let visitor = VecVisitor {
marker: PhantomData,
};
deserializer.deserialize_seq(visitor)
}
fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error>
where
D: Deserializer<'de>,
{
struct VecInPlaceVisitor<'a, T: 'a>(&'a mut Vec<T>);
impl<'a, 'de, T> Visitor<'de> for VecInPlaceVisitor<'a, T>
where
T: Deserialize<'de>,
{
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a sequence")
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let hint = size_hint::cautious(seq.size_hint());
if let Some(additional) = hint.checked_sub(self.0.len()) {
self.0.reserve(additional);
}
for i in 0..self.0.len() {
let next = {
let next_place = InPlaceSeed(&mut self.0[i]);
try!(seq.next_element_seed(next_place))
};
if next.is_none() {
self.0.truncate(i);
return Ok(());
}
}
while let Some(value) = try!(seq.next_element()) {
self.0.push(value);
}
Ok(())
}
}
deserializer.deserialize_seq(VecInPlaceVisitor(place))
}
}
////////////////////////////////////////////////////////////////////////////////
struct ArrayVisitor<A> {
marker: PhantomData<A>,
}
struct ArrayInPlaceVisitor<'a, A: 'a>(&'a mut A);
impl<A> ArrayVisitor<A> {
fn new() -> Self {
ArrayVisitor {
marker: PhantomData,
}
}
}
impl<'de, T> Visitor<'de> for ArrayVisitor<[T; 0]> {
type Value = [T; 0];
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("an empty array")
}
#[inline]
fn visit_seq<A>(self, _: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
Ok([])
}
}
// Does not require T: Deserialize<'de>.
impl<'de, T> Deserialize<'de> for [T; 0] {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_tuple(0, ArrayVisitor::<[T; 0]>::new())
}
}
macro_rules! array_impls {
($($len:expr => ($($n:tt)+))+) => {
$(
impl<'de, T> Visitor<'de> for ArrayVisitor<[T; $len]>
where
T: Deserialize<'de>,
{
type Value = [T; $len];
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(concat!("an array of length ", $len))
}
#[inline]
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
Ok([$(
match try!(seq.next_element()) {
Some(val) => val,
None => return Err(Error::invalid_length($n, &self)),
}
),+])
}
}
impl<'a, 'de, T> Visitor<'de> for ArrayInPlaceVisitor<'a, [T; $len]>
where
T: Deserialize<'de>,
{
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(concat!("an array of length ", $len))
}
#[inline]
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let mut fail_idx = None;
for (idx, dest) in self.0[..].iter_mut().enumerate() {
if try!(seq.next_element_seed(InPlaceSeed(dest))).is_none() {
fail_idx = Some(idx);
break;
}
}
if let Some(idx) = fail_idx {
return Err(Error::invalid_length(idx, &self));
}
Ok(())
}
}
impl<'de, T> Deserialize<'de> for [T; $len]
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_tuple($len, ArrayVisitor::<[T; $len]>::new())
}
fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_tuple($len, ArrayInPlaceVisitor(place))
}
}
)+
}
}
array_impls! {
1 => (0)
2 => (0 1)
3 => (0 1 2)
4 => (0 1 2 3)
5 => (0 1 2 3 4)
6 => (0 1 2 3 4 5)
7 => (0 1 2 3 4 5 6)
8 => (0 1 2 3 4 5 6 7)
9 => (0 1 2 3 4 5 6 7 8)
10 => (0 1 2 3 4 5 6 7 8 9)
11 => (0 1 2 3 4 5 6 7 8 9 10)
12 => (0 1 2 3 4 5 6 7 8 9 10 11)
13 => (0 1 2 3 4 5 6 7 8 9 10 11 12)
14 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13)
15 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14)
16 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15)
17 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16)
18 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17)
19 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18)
20 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19)
21 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20)
22 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21)
23 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22)
24 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23)
25 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24)
26 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25)
27 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26)
28 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27)
29 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28)
30 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29)
31 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30)
32 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31)
}
////////////////////////////////////////////////////////////////////////////////
macro_rules! tuple_impls {
($($len:tt => ($($n:tt $name:ident)+))+) => {
$(
impl<'de, $($name: Deserialize<'de>),+> Deserialize<'de> for ($($name,)+) {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct TupleVisitor<$($name,)+> {
marker: PhantomData<($($name,)+)>,
}
impl<'de, $($name: Deserialize<'de>),+> Visitor<'de> for TupleVisitor<$($name,)+> {
type Value = ($($name,)+);
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(concat!("a tuple of size ", $len))
}
#[inline]
#[allow(non_snake_case)]
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
$(
let $name = match try!(seq.next_element()) {
Some(value) => value,
None => return Err(Error::invalid_length($n, &self)),
};
)+
Ok(($($name,)+))
}
}
deserializer.deserialize_tuple($len, TupleVisitor { marker: PhantomData })
}
#[inline]
fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error>
where
D: Deserializer<'de>,
{
struct TupleInPlaceVisitor<'a, $($name: 'a,)+>(&'a mut ($($name,)+));
impl<'a, 'de, $($name: Deserialize<'de>),+> Visitor<'de> for TupleInPlaceVisitor<'a, $($name,)+> {
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(concat!("a tuple of size ", $len))
}
#[inline]
#[allow(non_snake_case)]
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
$(
if try!(seq.next_element_seed(InPlaceSeed(&mut (self.0).$n))).is_none() {
return Err(Error::invalid_length($n, &self));
}
)+
Ok(())
}
}
deserializer.deserialize_tuple($len, TupleInPlaceVisitor(place))
}
}
)+
}
}
tuple_impls! {
1 => (0 T0)
2 => (0 T0 1 T1)
3 => (0 T0 1 T1 2 T2)
4 => (0 T0 1 T1 2 T2 3 T3)
5 => (0 T0 1 T1 2 T2 3 T3 4 T4)
6 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5)
7 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6)
8 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7)
9 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8)
10 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9)
11 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10)
12 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11)
13 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12)
14 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13)
15 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13 14 T14)
16 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13 14 T14 15 T15)
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(any(feature = "std", feature = "alloc"))]
macro_rules! map_impl {
(
$ty:ident <K $(: $kbound1:ident $(+ $kbound2:ident)*)*, V $(, $typaram:ident : $bound1:ident $(+ $bound2:ident)*)*>,
$access:ident,
$with_capacity:expr
) => {
impl<'de, K, V $(, $typaram)*> Deserialize<'de> for $ty<K, V $(, $typaram)*>
where
K: Deserialize<'de> $(+ $kbound1 $(+ $kbound2)*)*,
V: Deserialize<'de>,
$($typaram: $bound1 $(+ $bound2)*),*
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct MapVisitor<K, V $(, $typaram)*> {
marker: PhantomData<$ty<K, V $(, $typaram)*>>,
}
impl<'de, K, V $(, $typaram)*> Visitor<'de> for MapVisitor<K, V $(, $typaram)*>
where
K: Deserialize<'de> $(+ $kbound1 $(+ $kbound2)*)*,
V: Deserialize<'de>,
$($typaram: $bound1 $(+ $bound2)*),*
{
type Value = $ty<K, V $(, $typaram)*>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a map")
}
#[inline]
fn visit_map<A>(self, mut $access: A) -> Result<Self::Value, A::Error>
where
A: MapAccess<'de>,
{
let mut values = $with_capacity;
while let Some((key, value)) = try!($access.next_entry()) {
values.insert(key, value);
}
Ok(values)
}
}
let visitor = MapVisitor { marker: PhantomData };
deserializer.deserialize_map(visitor)
}
}
}
}
#[cfg(any(feature = "std", feature = "alloc"))]
map_impl!(
BTreeMap<K: Ord, V>,
map,
BTreeMap::new());
#[cfg(feature = "std")]
map_impl!(
HashMap<K: Eq + Hash, V, S: BuildHasher + Default>,
map,
HashMap::with_capacity_and_hasher(size_hint::cautious(map.size_hint()), S::default()));
////////////////////////////////////////////////////////////////////////////////
#[cfg(feature = "std")]
macro_rules! parse_ip_impl {
($expecting:tt $ty:ty; $size:tt) => {
impl<'de> Deserialize<'de> for $ty {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
if deserializer.is_human_readable() {
deserializer.deserialize_str(FromStrVisitor::new($expecting))
} else {
<[u8; $size]>::deserialize(deserializer).map(<$ty>::from)
}
}
}
};
}
#[cfg(feature = "std")]
macro_rules! variant_identifier {
(
$name_kind:ident ($($variant:ident; $bytes:expr; $index:expr),*)
$expecting_message:expr,
$variants_name:ident
) => {
enum $name_kind {
$($variant),*
}
static $variants_name: &'static [&'static str] = &[$(stringify!($variant)),*];
impl<'de> Deserialize<'de> for $name_kind {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct KindVisitor;
impl<'de> Visitor<'de> for KindVisitor {
type Value = $name_kind;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str($expecting_message)
}
fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E>
where
E: Error,
{
match value {
$(
$index => Ok($name_kind :: $variant),
)*
_ => Err(Error::invalid_value(Unexpected::Unsigned(value), &self),),
}
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: Error,
{
match value {
$(
stringify!($variant) => Ok($name_kind :: $variant),
)*
_ => Err(Error::unknown_variant(value, $variants_name)),
}
}
fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match value {
$(
$bytes => Ok($name_kind :: $variant),
)*
_ => {
match str::from_utf8(value) {
Ok(value) => Err(Error::unknown_variant(value, $variants_name)),
Err(_) => Err(Error::invalid_value(Unexpected::Bytes(value), &self)),
}
}
}
}
}
deserializer.deserialize_identifier(KindVisitor)
}
}
}
}
#[cfg(feature = "std")]
macro_rules! deserialize_enum {
(
$name:ident $name_kind:ident ($($variant:ident; $bytes:expr; $index:expr),*)
$expecting_message:expr,
$deserializer:expr
) => {
variant_identifier! {
$name_kind ($($variant; $bytes; $index),*)
$expecting_message,
VARIANTS
}
struct EnumVisitor;
impl<'de> Visitor<'de> for EnumVisitor {
type Value = $name;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(concat!("a ", stringify!($name)))
}
fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error>
where
A: EnumAccess<'de>,
{
match try!(data.variant()) {
$(
($name_kind :: $variant, v) => v.newtype_variant().map($name :: $variant),
)*
}
}
}
$deserializer.deserialize_enum(stringify!($name), VARIANTS, EnumVisitor)
}
}
#[cfg(feature = "std")]
impl<'de> Deserialize<'de> for net::IpAddr {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
if deserializer.is_human_readable() {
deserializer.deserialize_str(FromStrVisitor::new("IP address"))
} else {
use lib::net::IpAddr;
deserialize_enum! {
IpAddr IpAddrKind (V4; b"V4"; 0, V6; b"V6"; 1)
"`V4` or `V6`",
deserializer
}
}
}
}
#[cfg(feature = "std")]
parse_ip_impl!("IPv4 address" net::Ipv4Addr; 4);
#[cfg(feature = "std")]
parse_ip_impl!("IPv6 address" net::Ipv6Addr; 16);
#[cfg(feature = "std")]
macro_rules! parse_socket_impl {
($expecting:tt $ty:ty, $new:expr) => {
impl<'de> Deserialize<'de> for $ty {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
if deserializer.is_human_readable() {
deserializer.deserialize_str(FromStrVisitor::new($expecting))
} else {
<(_, u16)>::deserialize(deserializer).map(|(ip, port)| $new(ip, port))
}
}
}
};
}
#[cfg(feature = "std")]
impl<'de> Deserialize<'de> for net::SocketAddr {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
if deserializer.is_human_readable() {
deserializer.deserialize_str(FromStrVisitor::new("socket address"))
} else {
use lib::net::SocketAddr;
deserialize_enum! {
SocketAddr SocketAddrKind (V4; b"V4"; 0, V6; b"V6"; 1)
"`V4` or `V6`",
deserializer
}
}
}
}
#[cfg(feature = "std")]
parse_socket_impl!("IPv4 socket address" net::SocketAddrV4, net::SocketAddrV4::new);
#[cfg(feature = "std")]
parse_socket_impl!("IPv6 socket address" net::SocketAddrV6, |ip, port| net::SocketAddrV6::new(
ip, port, 0, 0
));
////////////////////////////////////////////////////////////////////////////////
#[cfg(feature = "std")]
struct PathVisitor;
#[cfg(feature = "std")]
impl<'a> Visitor<'a> for PathVisitor {
type Value = &'a Path;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a borrowed path")
}
fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E>
where
E: Error,
{
Ok(v.as_ref())
}
fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E>
where
E: Error,
{
str::from_utf8(v)
.map(AsRef::as_ref)
.map_err(|_| Error::invalid_value(Unexpected::Bytes(v), &self))
}
}
#[cfg(feature = "std")]
impl<'de: 'a, 'a> Deserialize<'de> for &'a Path {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_str(PathVisitor)
}
}
#[cfg(feature = "std")]
struct PathBufVisitor;
#[cfg(feature = "std")]
impl<'de> Visitor<'de> for PathBufVisitor {
type Value = PathBuf;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("path string")
}
fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
where
E: Error,
{
Ok(From::from(v))
}
fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
where
E: Error,
{
Ok(From::from(v))
}
fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
str::from_utf8(v)
.map(From::from)
.map_err(|_| Error::invalid_value(Unexpected::Bytes(v), &self))
}
fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
where
E: Error,
{
String::from_utf8(v)
.map(From::from)
.map_err(|e| Error::invalid_value(Unexpected::Bytes(&e.into_bytes()), &self))
}
}
#[cfg(feature = "std")]
impl<'de> Deserialize<'de> for PathBuf {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_string(PathBufVisitor)
}
}
#[cfg(all(feature = "std", not(no_de_boxed_path)))]
forwarded_impl!((), Box<Path>, PathBuf::into_boxed_path);
////////////////////////////////////////////////////////////////////////////////
// If this were outside of the serde crate, it would just use:
//
// #[derive(Deserialize)]
// #[serde(variant_identifier)]
#[cfg(all(feature = "std", any(unix, windows)))]
variant_identifier! {
OsStringKind (Unix; b"Unix"; 0, Windows; b"Windows"; 1)
"`Unix` or `Windows`",
OSSTR_VARIANTS
}
#[cfg(all(feature = "std", any(unix, windows)))]
struct OsStringVisitor;
#[cfg(all(feature = "std", any(unix, windows)))]
impl<'de> Visitor<'de> for OsStringVisitor {
type Value = OsString;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("os string")
}
#[cfg(unix)]
fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error>
where
A: EnumAccess<'de>,
{
use std::os::unix::ffi::OsStringExt;
match try!(data.variant()) {
(OsStringKind::Unix, v) => v.newtype_variant().map(OsString::from_vec),
(OsStringKind::Windows, _) => Err(Error::custom(
"cannot deserialize Windows OS string on Unix",
)),
}
}
#[cfg(windows)]
fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error>
where
A: EnumAccess<'de>,
{
use std::os::windows::ffi::OsStringExt;
match try!(data.variant()) {
(OsStringKind::Windows, v) => v
.newtype_variant::<Vec<u16>>()
.map(|vec| OsString::from_wide(&vec)),
(OsStringKind::Unix, _) => Err(Error::custom(
"cannot deserialize Unix OS string on Windows",
)),
}
}
}
#[cfg(all(feature = "std", any(unix, windows)))]
impl<'de> Deserialize<'de> for OsString {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_enum("OsString", OSSTR_VARIANTS, OsStringVisitor)
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(any(feature = "std", feature = "alloc"))]
forwarded_impl!((T), Box<T>, Box::new);
#[cfg(any(feature = "std", feature = "alloc"))]
forwarded_impl!((T), Box<[T]>, Vec::into_boxed_slice);
#[cfg(any(feature = "std", feature = "alloc"))]
forwarded_impl!((), Box<str>, String::into_boxed_str);
#[cfg(all(no_de_rc_dst, feature = "rc", any(feature = "std", feature = "alloc")))]
forwarded_impl! {
/// This impl requires the [`"rc"`] Cargo feature of Serde.
///
/// Deserializing a data structure containing `Arc` will not attempt to
/// deduplicate `Arc` references to the same data. Every deserialized `Arc`
/// will end up with a strong count of 1.
///
/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
(T), Arc<T>, Arc::new
}
#[cfg(all(no_de_rc_dst, feature = "rc", any(feature = "std", feature = "alloc")))]
forwarded_impl! {
/// This impl requires the [`"rc"`] Cargo feature of Serde.
///
/// Deserializing a data structure containing `Rc` will not attempt to
/// deduplicate `Rc` references to the same data. Every deserialized `Rc`
/// will end up with a strong count of 1.
///
/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
(T), Rc<T>, Rc::new
}
#[cfg(any(feature = "std", feature = "alloc"))]
impl<'de, 'a, T: ?Sized> Deserialize<'de> for Cow<'a, T>
where
T: ToOwned,
T::Owned: Deserialize<'de>,
{
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
T::Owned::deserialize(deserializer).map(Cow::Owned)
}
}
////////////////////////////////////////////////////////////////////////////////
/// This impl requires the [`"rc"`] Cargo feature of Serde. The resulting
/// `Weak<T>` has a reference count of 0 and cannot be upgraded.
///
/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))]
impl<'de, T: ?Sized> Deserialize<'de> for RcWeak<T>
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
try!(Option::<T>::deserialize(deserializer));
Ok(RcWeak::new())
}
}
/// This impl requires the [`"rc"`] Cargo feature of Serde. The resulting
/// `Weak<T>` has a reference count of 0 and cannot be upgraded.
///
/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))]
impl<'de, T: ?Sized> Deserialize<'de> for ArcWeak<T>
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
try!(Option::<T>::deserialize(deserializer));
Ok(ArcWeak::new())
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(all(
not(no_de_rc_dst),
feature = "rc",
any(feature = "std", feature = "alloc")
))]
macro_rules! box_forwarded_impl {
(
$(#[doc = $doc:tt])*
$t:ident
) => {
$(#[doc = $doc])*
impl<'de, T: ?Sized> Deserialize<'de> for $t<T>
where
Box<T>: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
Box::deserialize(deserializer).map(Into::into)
}
}
};
}
#[cfg(all(
not(no_de_rc_dst),
feature = "rc",
any(feature = "std", feature = "alloc")
))]
box_forwarded_impl! {
/// This impl requires the [`"rc"`] Cargo feature of Serde.
///
/// Deserializing a data structure containing `Rc` will not attempt to
/// deduplicate `Rc` references to the same data. Every deserialized `Rc`
/// will end up with a strong count of 1.
///
/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
Rc
}
#[cfg(all(
not(no_de_rc_dst),
feature = "rc",
any(feature = "std", feature = "alloc")
))]
box_forwarded_impl! {
/// This impl requires the [`"rc"`] Cargo feature of Serde.
///
/// Deserializing a data structure containing `Arc` will not attempt to
/// deduplicate `Arc` references to the same data. Every deserialized `Arc`
/// will end up with a strong count of 1.
///
/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
Arc
}
////////////////////////////////////////////////////////////////////////////////
impl<'de, T> Deserialize<'de> for Cell<T>
where
T: Deserialize<'de> + Copy,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
T::deserialize(deserializer).map(Cell::new)
}
}
forwarded_impl!((T), RefCell<T>, RefCell::new);
#[cfg(feature = "std")]
forwarded_impl!((T), Mutex<T>, Mutex::new);
#[cfg(feature = "std")]
forwarded_impl!((T), RwLock<T>, RwLock::new);
////////////////////////////////////////////////////////////////////////////////
// This is a cleaned-up version of the impl generated by:
//
// #[derive(Deserialize)]
// #[serde(deny_unknown_fields)]
// struct Duration {
// secs: u64,
// nanos: u32,
// }
#[cfg(any(feature = "std", not(no_core_duration)))]
impl<'de> Deserialize<'de> for Duration {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
// If this were outside of the serde crate, it would just use:
//
// #[derive(Deserialize)]
// #[serde(field_identifier, rename_all = "lowercase")]
enum Field {
Secs,
Nanos,
}
impl<'de> Deserialize<'de> for Field {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct FieldVisitor;
impl<'de> Visitor<'de> for FieldVisitor {
type Value = Field;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("`secs` or `nanos`")
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: Error,
{
match value {
"secs" => Ok(Field::Secs),
"nanos" => Ok(Field::Nanos),
_ => Err(Error::unknown_field(value, FIELDS)),
}
}
fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match value {
b"secs" => Ok(Field::Secs),
b"nanos" => Ok(Field::Nanos),
_ => {
let value = ::__private::from_utf8_lossy(value);
Err(Error::unknown_field(&*value, FIELDS))
}
}
}
}
deserializer.deserialize_identifier(FieldVisitor)
}
}
fn check_overflow<E>(secs: u64, nanos: u32) -> Result<(), E>
where
E: Error,
{
static NANOS_PER_SEC: u32 = 1_000_000_000;
match secs.checked_add((nanos / NANOS_PER_SEC) as u64) {
Some(_) => Ok(()),
None => Err(E::custom("overflow deserializing Duration")),
}
}
struct DurationVisitor;
impl<'de> Visitor<'de> for DurationVisitor {
type Value = Duration;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("struct Duration")
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let secs: u64 = match try!(seq.next_element()) {
Some(value) => value,
None => {
return Err(Error::invalid_length(0, &self));
}
};
let nanos: u32 = match try!(seq.next_element()) {
Some(value) => value,
None => {
return Err(Error::invalid_length(1, &self));
}
};
try!(check_overflow(secs, nanos));
Ok(Duration::new(secs, nanos))
}
fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
where
A: MapAccess<'de>,
{
let mut secs: Option<u64> = None;
let mut nanos: Option<u32> = None;
while let Some(key) = try!(map.next_key()) {
match key {
Field::Secs => {
if secs.is_some() {
return Err(<A::Error as Error>::duplicate_field("secs"));
}
secs = Some(try!(map.next_value()));
}
Field::Nanos => {
if nanos.is_some() {
return Err(<A::Error as Error>::duplicate_field("nanos"));
}
nanos = Some(try!(map.next_value()));
}
}
}
let secs = match secs {
Some(secs) => secs,
None => return Err(<A::Error as Error>::missing_field("secs")),
};
let nanos = match nanos {
Some(nanos) => nanos,
None => return Err(<A::Error as Error>::missing_field("nanos")),
};
try!(check_overflow(secs, nanos));
Ok(Duration::new(secs, nanos))
}
}
const FIELDS: &'static [&'static str] = &["secs", "nanos"];
deserializer.deserialize_struct("Duration", FIELDS, DurationVisitor)
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(feature = "std")]
impl<'de> Deserialize<'de> for SystemTime {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
// Reuse duration
enum Field {
Secs,
Nanos,
}
impl<'de> Deserialize<'de> for Field {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct FieldVisitor;
impl<'de> Visitor<'de> for FieldVisitor {
type Value = Field;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("`secs_since_epoch` or `nanos_since_epoch`")
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: Error,
{
match value {
"secs_since_epoch" => Ok(Field::Secs),
"nanos_since_epoch" => Ok(Field::Nanos),
_ => Err(Error::unknown_field(value, FIELDS)),
}
}
fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match value {
b"secs_since_epoch" => Ok(Field::Secs),
b"nanos_since_epoch" => Ok(Field::Nanos),
_ => {
let value = String::from_utf8_lossy(value);
Err(Error::unknown_field(&value, FIELDS))
}
}
}
}
deserializer.deserialize_identifier(FieldVisitor)
}
}
fn check_overflow<E>(secs: u64, nanos: u32) -> Result<(), E>
where
E: Error,
{
static NANOS_PER_SEC: u32 = 1_000_000_000;
match secs.checked_add((nanos / NANOS_PER_SEC) as u64) {
Some(_) => Ok(()),
None => Err(E::custom("overflow deserializing SystemTime epoch offset")),
}
}
struct DurationVisitor;
impl<'de> Visitor<'de> for DurationVisitor {
type Value = Duration;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("struct SystemTime")
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let secs: u64 = match try!(seq.next_element()) {
Some(value) => value,
None => {
return Err(Error::invalid_length(0, &self));
}
};
let nanos: u32 = match try!(seq.next_element()) {
Some(value) => value,
None => {
return Err(Error::invalid_length(1, &self));
}
};
try!(check_overflow(secs, nanos));
Ok(Duration::new(secs, nanos))
}
fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
where
A: MapAccess<'de>,
{
let mut secs: Option<u64> = None;
let mut nanos: Option<u32> = None;
while let Some(key) = try!(map.next_key()) {
match key {
Field::Secs => {
if secs.is_some() {
return Err(<A::Error as Error>::duplicate_field(
"secs_since_epoch",
));
}
secs = Some(try!(map.next_value()));
}
Field::Nanos => {
if nanos.is_some() {
return Err(<A::Error as Error>::duplicate_field(
"nanos_since_epoch",
));
}
nanos = Some(try!(map.next_value()));
}
}
}
let secs = match secs {
Some(secs) => secs,
None => return Err(<A::Error as Error>::missing_field("secs_since_epoch")),
};
let nanos = match nanos {
Some(nanos) => nanos,
None => return Err(<A::Error as Error>::missing_field("nanos_since_epoch")),
};
try!(check_overflow(secs, nanos));
Ok(Duration::new(secs, nanos))
}
}
const FIELDS: &'static [&'static str] = &["secs_since_epoch", "nanos_since_epoch"];
let duration = try!(deserializer.deserialize_struct("SystemTime", FIELDS, DurationVisitor));
#[cfg(not(no_systemtime_checked_add))]
let ret = UNIX_EPOCH
.checked_add(duration)
.ok_or_else(|| D::Error::custom("overflow deserializing SystemTime"));
#[cfg(no_systemtime_checked_add)]
let ret = Ok(UNIX_EPOCH + duration);
ret
}
}
////////////////////////////////////////////////////////////////////////////////
// Similar to:
//
// #[derive(Deserialize)]
// #[serde(deny_unknown_fields)]
// struct Range {
// start: u64,
// end: u32,
// }
impl<'de, Idx> Deserialize<'de> for Range<Idx>
where
Idx: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
let (start, end) = try!(deserializer.deserialize_struct(
"Range",
range::FIELDS,
range::RangeVisitor {
expecting: "struct Range",
phantom: PhantomData,
},
));
Ok(start..end)
}
}
#[cfg(not(no_range_inclusive))]
impl<'de, Idx> Deserialize<'de> for RangeInclusive<Idx>
where
Idx: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
let (start, end) = try!(deserializer.deserialize_struct(
"RangeInclusive",
range::FIELDS,
range::RangeVisitor {
expecting: "struct RangeInclusive",
phantom: PhantomData,
},
));
Ok(RangeInclusive::new(start, end))
}
}
mod range {
use lib::*;
use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
pub const FIELDS: &'static [&'static str] = &["start", "end"];
// If this were outside of the serde crate, it would just use:
//
// #[derive(Deserialize)]
// #[serde(field_identifier, rename_all = "lowercase")]
enum Field {
Start,
End,
}
impl<'de> Deserialize<'de> for Field {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct FieldVisitor;
impl<'de> Visitor<'de> for FieldVisitor {
type Value = Field;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("`start` or `end`")
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: Error,
{
match value {
"start" => Ok(Field::Start),
"end" => Ok(Field::End),
_ => Err(Error::unknown_field(value, FIELDS)),
}
}
fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match value {
b"start" => Ok(Field::Start),
b"end" => Ok(Field::End),
_ => {
let value = ::__private::from_utf8_lossy(value);
Err(Error::unknown_field(&*value, FIELDS))
}
}
}
}
deserializer.deserialize_identifier(FieldVisitor)
}
}
pub struct RangeVisitor<Idx> {
pub expecting: &'static str,
pub phantom: PhantomData<Idx>,
}
impl<'de, Idx> Visitor<'de> for RangeVisitor<Idx>
where
Idx: Deserialize<'de>,
{
type Value = (Idx, Idx);
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(self.expecting)
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let start: Idx = match try!(seq.next_element()) {
Some(value) => value,
None => {
return Err(Error::invalid_length(0, &self));
}
};
let end: Idx = match try!(seq.next_element()) {
Some(value) => value,
None => {
return Err(Error::invalid_length(1, &self));
}
};
Ok((start, end))
}
fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
where
A: MapAccess<'de>,
{
let mut start: Option<Idx> = None;
let mut end: Option<Idx> = None;
while let Some(key) = try!(map.next_key()) {
match key {
Field::Start => {
if start.is_some() {
return Err(<A::Error as Error>::duplicate_field("start"));
}
start = Some(try!(map.next_value()));
}
Field::End => {
if end.is_some() {
return Err(<A::Error as Error>::duplicate_field("end"));
}
end = Some(try!(map.next_value()));
}
}
}
let start = match start {
Some(start) => start,
None => return Err(<A::Error as Error>::missing_field("start")),
};
let end = match end {
Some(end) => end,
None => return Err(<A::Error as Error>::missing_field("end")),
};
Ok((start, end))
}
}
}
////////////////////////////////////////////////////////////////////////////////
#[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))]
impl<'de, T> Deserialize<'de> for Bound<T>
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
enum Field {
Unbounded,
Included,
Excluded,
}
impl<'de> Deserialize<'de> for Field {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct FieldVisitor;
impl<'de> Visitor<'de> for FieldVisitor {
type Value = Field;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("`Unbounded`, `Included` or `Excluded`")
}
fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E>
where
E: Error,
{
match value {
0 => Ok(Field::Unbounded),
1 => Ok(Field::Included),
2 => Ok(Field::Excluded),
_ => Err(Error::invalid_value(Unexpected::Unsigned(value), &self)),
}
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: Error,
{
match value {
"Unbounded" => Ok(Field::Unbounded),
"Included" => Ok(Field::Included),
"Excluded" => Ok(Field::Excluded),
_ => Err(Error::unknown_variant(value, VARIANTS)),
}
}
fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match value {
b"Unbounded" => Ok(Field::Unbounded),
b"Included" => Ok(Field::Included),
b"Excluded" => Ok(Field::Excluded),
_ => match str::from_utf8(value) {
Ok(value) => Err(Error::unknown_variant(value, VARIANTS)),
Err(_) => {
Err(Error::invalid_value(Unexpected::Bytes(value), &self))
}
},
}
}
}
deserializer.deserialize_identifier(FieldVisitor)
}
}
struct BoundVisitor<T>(PhantomData<Bound<T>>);
impl<'de, T> Visitor<'de> for BoundVisitor<T>
where
T: Deserialize<'de>,
{
type Value = Bound<T>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("enum Bound")
}
fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error>
where
A: EnumAccess<'de>,
{
match try!(data.variant()) {
(Field::Unbounded, v) => v.unit_variant().map(|()| Bound::Unbounded),
(Field::Included, v) => v.newtype_variant().map(Bound::Included),
(Field::Excluded, v) => v.newtype_variant().map(Bound::Excluded),
}
}
}
const VARIANTS: &'static [&'static str] = &["Unbounded", "Included", "Excluded"];
deserializer.deserialize_enum("Bound", VARIANTS, BoundVisitor(PhantomData))
}
}
////////////////////////////////////////////////////////////////////////////////
impl<'de, T, E> Deserialize<'de> for Result<T, E>
where
T: Deserialize<'de>,
E: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
// If this were outside of the serde crate, it would just use:
//
// #[derive(Deserialize)]
// #[serde(variant_identifier)]
enum Field {
Ok,
Err,
}
impl<'de> Deserialize<'de> for Field {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
struct FieldVisitor;
impl<'de> Visitor<'de> for FieldVisitor {
type Value = Field;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("`Ok` or `Err`")
}
fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E>
where
E: Error,
{
match value {
0 => Ok(Field::Ok),
1 => Ok(Field::Err),
_ => Err(Error::invalid_value(Unexpected::Unsigned(value), &self)),
}
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: Error,
{
match value {
"Ok" => Ok(Field::Ok),
"Err" => Ok(Field::Err),
_ => Err(Error::unknown_variant(value, VARIANTS)),
}
}
fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
match value {
b"Ok" => Ok(Field::Ok),
b"Err" => Ok(Field::Err),
_ => match str::from_utf8(value) {
Ok(value) => Err(Error::unknown_variant(value, VARIANTS)),
Err(_) => {
Err(Error::invalid_value(Unexpected::Bytes(value), &self))
}
},
}
}
}
deserializer.deserialize_identifier(FieldVisitor)
}
}
struct ResultVisitor<T, E>(PhantomData<Result<T, E>>);
impl<'de, T, E> Visitor<'de> for ResultVisitor<T, E>
where
T: Deserialize<'de>,
E: Deserialize<'de>,
{
type Value = Result<T, E>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("enum Result")
}
fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error>
where
A: EnumAccess<'de>,
{
match try!(data.variant()) {
(Field::Ok, v) => v.newtype_variant().map(Ok),
(Field::Err, v) => v.newtype_variant().map(Err),
}
}
}
const VARIANTS: &'static [&'static str] = &["Ok", "Err"];
deserializer.deserialize_enum("Result", VARIANTS, ResultVisitor(PhantomData))
}
}
////////////////////////////////////////////////////////////////////////////////
impl<'de, T> Deserialize<'de> for Wrapping<T>
where
T: Deserialize<'de>,
{
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
Deserialize::deserialize(deserializer).map(Wrapping)
}
}
#[cfg(all(feature = "std", not(no_std_atomic)))]
macro_rules! atomic_impl {
($($ty:ident $size:expr)*) => {
$(
#[cfg(any(no_target_has_atomic, target_has_atomic = $size))]
impl<'de> Deserialize<'de> for $ty {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
Deserialize::deserialize(deserializer).map(Self::new)
}
}
)*
};
}
#[cfg(all(feature = "std", not(no_std_atomic)))]
atomic_impl! {
AtomicBool "8"
AtomicI8 "8"
AtomicI16 "16"
AtomicI32 "32"
AtomicIsize "ptr"
AtomicU8 "8"
AtomicU16 "16"
AtomicU32 "32"
AtomicUsize "ptr"
}
#[cfg(all(feature = "std", not(no_std_atomic64)))]
atomic_impl! {
AtomicI64 "64"
AtomicU64 "64"
}
#[cfg(feature = "std")]
struct FromStrVisitor<T> {
expecting: &'static str,
ty: PhantomData<T>,
}
#[cfg(feature = "std")]
impl<T> FromStrVisitor<T> {
fn new(expecting: &'static str) -> Self {
FromStrVisitor {
expecting: expecting,
ty: PhantomData,
}
}
}
#[cfg(feature = "std")]
impl<'de, T> Visitor<'de> for FromStrVisitor<T>
where
T: str::FromStr,
T::Err: fmt::Display,
{
type Value = T;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(self.expecting)
}
fn visit_str<E>(self, s: &str) -> Result<Self::Value, E>
where
E: Error,
{
s.parse().map_err(Error::custom)
}
}