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-rw-r--r--vendor/serde/src/de/value.rs1720
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diff --git a/vendor/serde/src/de/value.rs b/vendor/serde/src/de/value.rs
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+++ b/vendor/serde/src/de/value.rs
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+//! Building blocks for deserializing basic values using the `IntoDeserializer`
+//! trait.
+//!
+//! ```edition2021
+//! use serde::de::{value, Deserialize, IntoDeserializer};
+//! use serde_derive::Deserialize;
+//! use std::str::FromStr;
+//!
+//! #[derive(Deserialize)]
+//! enum Setting {
+//! On,
+//! Off,
+//! }
+//!
+//! impl FromStr for Setting {
+//! type Err = value::Error;
+//!
+//! fn from_str(s: &str) -> Result<Self, Self::Err> {
+//! Self::deserialize(s.into_deserializer())
+//! }
+//! }
+//! ```
+
+use crate::lib::*;
+
+use self::private::{First, Second};
+use crate::de::{self, size_hint, Deserializer, Expected, IntoDeserializer, SeqAccess, Visitor};
+use crate::ser;
+
+////////////////////////////////////////////////////////////////////////////////
+
+// For structs that contain a PhantomData. We do not want the trait
+// bound `E: Clone` inferred by derive(Clone).
+macro_rules! impl_copy_clone {
+ ($ty:ident $(<$lifetime:tt>)*) => {
+ impl<$($lifetime,)* E> Copy for $ty<$($lifetime,)* E> {}
+
+ impl<$($lifetime,)* E> Clone for $ty<$($lifetime,)* E> {
+ fn clone(&self) -> Self {
+ *self
+ }
+ }
+ };
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A minimal representation of all possible errors that can occur using the
+/// `IntoDeserializer` trait.
+#[derive(Clone, PartialEq)]
+pub struct Error {
+ err: ErrorImpl,
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+type ErrorImpl = Box<str>;
+#[cfg(not(any(feature = "std", feature = "alloc")))]
+type ErrorImpl = ();
+
+impl de::Error for Error {
+ #[cfg(any(feature = "std", feature = "alloc"))]
+ #[cold]
+ fn custom<T>(msg: T) -> Self
+ where
+ T: Display,
+ {
+ Error {
+ err: msg.to_string().into_boxed_str(),
+ }
+ }
+
+ #[cfg(not(any(feature = "std", feature = "alloc")))]
+ #[cold]
+ fn custom<T>(msg: T) -> Self
+ where
+ T: Display,
+ {
+ let _ = msg;
+ Error { err: () }
+ }
+}
+
+impl ser::Error for Error {
+ #[cold]
+ fn custom<T>(msg: T) -> Self
+ where
+ T: Display,
+ {
+ de::Error::custom(msg)
+ }
+}
+
+impl Display for Error {
+ #[cfg(any(feature = "std", feature = "alloc"))]
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter.write_str(&self.err)
+ }
+
+ #[cfg(not(any(feature = "std", feature = "alloc")))]
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter.write_str("Serde deserialization error")
+ }
+}
+
+impl Debug for Error {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ let mut debug = formatter.debug_tuple("Error");
+ #[cfg(any(feature = "std", feature = "alloc"))]
+ debug.field(&self.err);
+ debug.finish()
+ }
+}
+
+#[cfg(feature = "std")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
+impl error::Error for Error {
+ fn description(&self) -> &str {
+ &self.err
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+impl<'de, E> IntoDeserializer<'de, E> for ()
+where
+ E: de::Error,
+{
+ type Deserializer = UnitDeserializer<E>;
+
+ fn into_deserializer(self) -> UnitDeserializer<E> {
+ UnitDeserializer::new()
+ }
+}
+
+/// A deserializer holding a `()`.
+pub struct UnitDeserializer<E> {
+ marker: PhantomData<E>,
+}
+
+impl_copy_clone!(UnitDeserializer);
+
+impl<E> UnitDeserializer<E> {
+ #[allow(missing_docs)]
+ pub fn new() -> Self {
+ UnitDeserializer {
+ marker: PhantomData,
+ }
+ }
+}
+
+impl<'de, E> de::Deserializer<'de> for UnitDeserializer<E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf unit unit_struct newtype_struct seq tuple tuple_struct
+ map struct enum identifier ignored_any
+ }
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_unit()
+ }
+
+ fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_none()
+ }
+}
+
+impl<E> Debug for UnitDeserializer<E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter.debug_struct("UnitDeserializer").finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer that cannot be instantiated.
+#[cfg(feature = "unstable")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "unstable")))]
+pub struct NeverDeserializer<E> {
+ never: !,
+ marker: PhantomData<E>,
+}
+
+#[cfg(feature = "unstable")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "unstable")))]
+impl<'de, E> IntoDeserializer<'de, E> for !
+where
+ E: de::Error,
+{
+ type Deserializer = NeverDeserializer<E>;
+
+ fn into_deserializer(self) -> Self::Deserializer {
+ self
+ }
+}
+
+#[cfg(feature = "unstable")]
+impl<'de, E> de::Deserializer<'de> for NeverDeserializer<E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ self.never
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct enum identifier ignored_any
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+macro_rules! primitive_deserializer {
+ ($ty:ty, $doc:tt, $name:ident, $method:ident $($cast:tt)*) => {
+ #[doc = "A deserializer holding"]
+ #[doc = $doc]
+ pub struct $name<E> {
+ value: $ty,
+ marker: PhantomData<E>
+ }
+
+ impl_copy_clone!($name);
+
+ impl<'de, E> IntoDeserializer<'de, E> for $ty
+ where
+ E: de::Error,
+ {
+ type Deserializer = $name<E>;
+
+ fn into_deserializer(self) -> $name<E> {
+ $name::new(self)
+ }
+ }
+
+ impl<E> $name<E> {
+ #[allow(missing_docs)]
+ pub fn new(value: $ty) -> Self {
+ $name {
+ value,
+ marker: PhantomData,
+ }
+ }
+ }
+
+ impl<'de, E> de::Deserializer<'de> for $name<E>
+ where
+ E: de::Error,
+ {
+ type Error = E;
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str
+ string bytes byte_buf option unit unit_struct newtype_struct seq
+ tuple tuple_struct map struct enum identifier ignored_any
+ }
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.$method(self.value $($cast)*)
+ }
+ }
+
+ impl<E> Debug for $name<E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct(stringify!($name))
+ .field("value", &self.value)
+ .finish()
+ }
+ }
+ }
+}
+
+primitive_deserializer!(bool, "a `bool`.", BoolDeserializer, visit_bool);
+primitive_deserializer!(i8, "an `i8`.", I8Deserializer, visit_i8);
+primitive_deserializer!(i16, "an `i16`.", I16Deserializer, visit_i16);
+primitive_deserializer!(i32, "an `i32`.", I32Deserializer, visit_i32);
+primitive_deserializer!(i64, "an `i64`.", I64Deserializer, visit_i64);
+primitive_deserializer!(i128, "an `i128`.", I128Deserializer, visit_i128);
+primitive_deserializer!(isize, "an `isize`.", IsizeDeserializer, visit_i64 as i64);
+primitive_deserializer!(u8, "a `u8`.", U8Deserializer, visit_u8);
+primitive_deserializer!(u16, "a `u16`.", U16Deserializer, visit_u16);
+primitive_deserializer!(u64, "a `u64`.", U64Deserializer, visit_u64);
+primitive_deserializer!(u128, "a `u128`.", U128Deserializer, visit_u128);
+primitive_deserializer!(usize, "a `usize`.", UsizeDeserializer, visit_u64 as u64);
+primitive_deserializer!(f32, "an `f32`.", F32Deserializer, visit_f32);
+primitive_deserializer!(f64, "an `f64`.", F64Deserializer, visit_f64);
+primitive_deserializer!(char, "a `char`.", CharDeserializer, visit_char);
+
+/// A deserializer holding a `u32`.
+pub struct U32Deserializer<E> {
+ value: u32,
+ marker: PhantomData<E>,
+}
+
+impl_copy_clone!(U32Deserializer);
+
+impl<'de, E> IntoDeserializer<'de, E> for u32
+where
+ E: de::Error,
+{
+ type Deserializer = U32Deserializer<E>;
+
+ fn into_deserializer(self) -> U32Deserializer<E> {
+ U32Deserializer::new(self)
+ }
+}
+
+impl<E> U32Deserializer<E> {
+ #[allow(missing_docs)]
+ pub fn new(value: u32) -> Self {
+ U32Deserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+impl<'de, E> de::Deserializer<'de> for U32Deserializer<E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct identifier ignored_any
+ }
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_u32(self.value)
+ }
+
+ fn deserialize_enum<V>(
+ self,
+ name: &str,
+ variants: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let _ = name;
+ let _ = variants;
+ visitor.visit_enum(self)
+ }
+}
+
+impl<'de, E> de::EnumAccess<'de> for U32Deserializer<E>
+where
+ E: de::Error,
+{
+ type Error = E;
+ type Variant = private::UnitOnly<E>;
+
+ fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ seed.deserialize(self).map(private::unit_only)
+ }
+}
+
+impl<E> Debug for U32Deserializer<E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("U32Deserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `&str`.
+pub struct StrDeserializer<'a, E> {
+ value: &'a str,
+ marker: PhantomData<E>,
+}
+
+impl_copy_clone!(StrDeserializer<'de>);
+
+impl<'de, 'a, E> IntoDeserializer<'de, E> for &'a str
+where
+ E: de::Error,
+{
+ type Deserializer = StrDeserializer<'a, E>;
+
+ fn into_deserializer(self) -> StrDeserializer<'a, E> {
+ StrDeserializer::new(self)
+ }
+}
+
+impl<'a, E> StrDeserializer<'a, E> {
+ #[allow(missing_docs)]
+ pub fn new(value: &'a str) -> Self {
+ StrDeserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+impl<'de, 'a, E> de::Deserializer<'de> for StrDeserializer<'a, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_str(self.value)
+ }
+
+ fn deserialize_enum<V>(
+ self,
+ name: &str,
+ variants: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let _ = name;
+ let _ = variants;
+ visitor.visit_enum(self)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct identifier ignored_any
+ }
+}
+
+impl<'de, 'a, E> de::EnumAccess<'de> for StrDeserializer<'a, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+ type Variant = private::UnitOnly<E>;
+
+ fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ seed.deserialize(self).map(private::unit_only)
+ }
+}
+
+impl<'a, E> Debug for StrDeserializer<'a, E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("StrDeserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `&str` with a lifetime tied to another
+/// deserializer.
+pub struct BorrowedStrDeserializer<'de, E> {
+ value: &'de str,
+ marker: PhantomData<E>,
+}
+
+impl_copy_clone!(BorrowedStrDeserializer<'de>);
+
+impl<'de, E> BorrowedStrDeserializer<'de, E> {
+ /// Create a new borrowed deserializer from the given string.
+ pub fn new(value: &'de str) -> BorrowedStrDeserializer<'de, E> {
+ BorrowedStrDeserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+impl<'de, E> de::Deserializer<'de> for BorrowedStrDeserializer<'de, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_borrowed_str(self.value)
+ }
+
+ fn deserialize_enum<V>(
+ self,
+ name: &str,
+ variants: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let _ = name;
+ let _ = variants;
+ visitor.visit_enum(self)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct identifier ignored_any
+ }
+}
+
+impl<'de, E> de::EnumAccess<'de> for BorrowedStrDeserializer<'de, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+ type Variant = private::UnitOnly<E>;
+
+ fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ seed.deserialize(self).map(private::unit_only)
+ }
+}
+
+impl<'de, E> Debug for BorrowedStrDeserializer<'de, E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("BorrowedStrDeserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `String`.
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+pub struct StringDeserializer<E> {
+ value: String,
+ marker: PhantomData<E>,
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<E> Clone for StringDeserializer<E> {
+ fn clone(&self) -> Self {
+ StringDeserializer {
+ value: self.value.clone(),
+ marker: PhantomData,
+ }
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+impl<'de, E> IntoDeserializer<'de, E> for String
+where
+ E: de::Error,
+{
+ type Deserializer = StringDeserializer<E>;
+
+ fn into_deserializer(self) -> StringDeserializer<E> {
+ StringDeserializer::new(self)
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<E> StringDeserializer<E> {
+ #[allow(missing_docs)]
+ pub fn new(value: String) -> Self {
+ StringDeserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'de, E> de::Deserializer<'de> for StringDeserializer<E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_string(self.value)
+ }
+
+ fn deserialize_enum<V>(
+ self,
+ name: &str,
+ variants: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let _ = name;
+ let _ = variants;
+ visitor.visit_enum(self)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct identifier ignored_any
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'de, E> de::EnumAccess<'de> for StringDeserializer<E>
+where
+ E: de::Error,
+{
+ type Error = E;
+ type Variant = private::UnitOnly<E>;
+
+ fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ seed.deserialize(self).map(private::unit_only)
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<E> Debug for StringDeserializer<E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("StringDeserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `Cow<str>`.
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+pub struct CowStrDeserializer<'a, E> {
+ value: Cow<'a, str>,
+ marker: PhantomData<E>,
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, E> Clone for CowStrDeserializer<'a, E> {
+ fn clone(&self) -> Self {
+ CowStrDeserializer {
+ value: self.value.clone(),
+ marker: PhantomData,
+ }
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str>
+where
+ E: de::Error,
+{
+ type Deserializer = CowStrDeserializer<'a, E>;
+
+ fn into_deserializer(self) -> CowStrDeserializer<'a, E> {
+ CowStrDeserializer::new(self)
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, E> CowStrDeserializer<'a, E> {
+ #[allow(missing_docs)]
+ pub fn new(value: Cow<'a, str>) -> Self {
+ CowStrDeserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'de, 'a, E> de::Deserializer<'de> for CowStrDeserializer<'a, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ match self.value {
+ Cow::Borrowed(string) => visitor.visit_str(string),
+ Cow::Owned(string) => visitor.visit_string(string),
+ }
+ }
+
+ fn deserialize_enum<V>(
+ self,
+ name: &str,
+ variants: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let _ = name;
+ let _ = variants;
+ visitor.visit_enum(self)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct identifier ignored_any
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'de, 'a, E> de::EnumAccess<'de> for CowStrDeserializer<'a, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+ type Variant = private::UnitOnly<E>;
+
+ fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ seed.deserialize(self).map(private::unit_only)
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, E> Debug for CowStrDeserializer<'a, E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("CowStrDeserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `&[u8]`. Always calls [`Visitor::visit_bytes`].
+pub struct BytesDeserializer<'a, E> {
+ value: &'a [u8],
+ marker: PhantomData<E>,
+}
+
+impl<'a, E> BytesDeserializer<'a, E> {
+ /// Create a new deserializer from the given bytes.
+ pub fn new(value: &'a [u8]) -> Self {
+ BytesDeserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+impl_copy_clone!(BytesDeserializer<'a>);
+
+impl<'de, 'a, E> IntoDeserializer<'de, E> for &'a [u8]
+where
+ E: de::Error,
+{
+ type Deserializer = BytesDeserializer<'a, E>;
+
+ fn into_deserializer(self) -> BytesDeserializer<'a, E> {
+ BytesDeserializer::new(self)
+ }
+}
+
+impl<'de, 'a, E> Deserializer<'de> for BytesDeserializer<'a, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: Visitor<'de>,
+ {
+ visitor.visit_bytes(self.value)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct enum identifier ignored_any
+ }
+}
+
+impl<'a, E> Debug for BytesDeserializer<'a, E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("BytesDeserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+/// A deserializer holding a `&[u8]` with a lifetime tied to another
+/// deserializer. Always calls [`Visitor::visit_borrowed_bytes`].
+pub struct BorrowedBytesDeserializer<'de, E> {
+ value: &'de [u8],
+ marker: PhantomData<E>,
+}
+
+impl<'de, E> BorrowedBytesDeserializer<'de, E> {
+ /// Create a new borrowed deserializer from the given borrowed bytes.
+ pub fn new(value: &'de [u8]) -> Self {
+ BorrowedBytesDeserializer {
+ value,
+ marker: PhantomData,
+ }
+ }
+}
+
+impl_copy_clone!(BorrowedBytesDeserializer<'de>);
+
+impl<'de, E> Deserializer<'de> for BorrowedBytesDeserializer<'de, E>
+where
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: Visitor<'de>,
+ {
+ visitor.visit_borrowed_bytes(self.value)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct enum identifier ignored_any
+ }
+}
+
+impl<'de, E> Debug for BorrowedBytesDeserializer<'de, E> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("BorrowedBytesDeserializer")
+ .field("value", &self.value)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer that iterates over a sequence.
+#[derive(Clone)]
+pub struct SeqDeserializer<I, E> {
+ iter: iter::Fuse<I>,
+ count: usize,
+ marker: PhantomData<E>,
+}
+
+impl<I, E> SeqDeserializer<I, E>
+where
+ I: Iterator,
+{
+ /// Construct a new `SeqDeserializer<I, E>`.
+ pub fn new(iter: I) -> Self {
+ SeqDeserializer {
+ iter: iter.fuse(),
+ count: 0,
+ marker: PhantomData,
+ }
+ }
+}
+
+impl<I, E> SeqDeserializer<I, E>
+where
+ I: Iterator,
+ E: de::Error,
+{
+ /// Check for remaining elements after passing a `SeqDeserializer` to
+ /// `Visitor::visit_seq`.
+ pub fn end(self) -> Result<(), E> {
+ let remaining = self.iter.count();
+ if remaining == 0 {
+ Ok(())
+ } else {
+ // First argument is the number of elements in the data, second
+ // argument is the number of elements expected by the Deserialize.
+ Err(de::Error::invalid_length(
+ self.count + remaining,
+ &ExpectedInSeq(self.count),
+ ))
+ }
+ }
+}
+
+impl<'de, I, T, E> de::Deserializer<'de> for SeqDeserializer<I, E>
+where
+ I: Iterator<Item = T>,
+ T: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let v = tri!(visitor.visit_seq(&mut self));
+ tri!(self.end());
+ Ok(v)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct enum identifier ignored_any
+ }
+}
+
+impl<'de, I, T, E> de::SeqAccess<'de> for SeqDeserializer<I, E>
+where
+ I: Iterator<Item = T>,
+ T: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ fn next_element_seed<V>(&mut self, seed: V) -> Result<Option<V::Value>, Self::Error>
+ where
+ V: de::DeserializeSeed<'de>,
+ {
+ match self.iter.next() {
+ Some(value) => {
+ self.count += 1;
+ seed.deserialize(value.into_deserializer()).map(Some)
+ }
+ None => Ok(None),
+ }
+ }
+
+ fn size_hint(&self) -> Option<usize> {
+ size_hint::from_bounds(&self.iter)
+ }
+}
+
+struct ExpectedInSeq(usize);
+
+impl Expected for ExpectedInSeq {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ if self.0 == 1 {
+ write!(formatter, "1 element in sequence")
+ } else {
+ write!(formatter, "{} elements in sequence", self.0)
+ }
+ }
+}
+
+impl<I, E> Debug for SeqDeserializer<I, E>
+where
+ I: Debug,
+{
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("SeqDeserializer")
+ .field("iter", &self.iter)
+ .field("count", &self.count)
+ .finish()
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+impl<'de, T, E> IntoDeserializer<'de, E> for Vec<T>
+where
+ T: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>;
+
+ fn into_deserializer(self) -> Self::Deserializer {
+ SeqDeserializer::new(self.into_iter())
+ }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+impl<'de, T, E> IntoDeserializer<'de, E> for BTreeSet<T>
+where
+ T: IntoDeserializer<'de, E> + Eq + Ord,
+ E: de::Error,
+{
+ type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>;
+
+ fn into_deserializer(self) -> Self::Deserializer {
+ SeqDeserializer::new(self.into_iter())
+ }
+}
+
+#[cfg(feature = "std")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
+impl<'de, T, S, E> IntoDeserializer<'de, E> for HashSet<T, S>
+where
+ T: IntoDeserializer<'de, E> + Eq + Hash,
+ S: BuildHasher,
+ E: de::Error,
+{
+ type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>;
+
+ fn into_deserializer(self) -> Self::Deserializer {
+ SeqDeserializer::new(self.into_iter())
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `SeqAccess`.
+#[derive(Clone, Debug)]
+pub struct SeqAccessDeserializer<A> {
+ seq: A,
+}
+
+impl<A> SeqAccessDeserializer<A> {
+ /// Construct a new `SeqAccessDeserializer<A>`.
+ pub fn new(seq: A) -> Self {
+ SeqAccessDeserializer { seq }
+ }
+}
+
+impl<'de, A> de::Deserializer<'de> for SeqAccessDeserializer<A>
+where
+ A: de::SeqAccess<'de>,
+{
+ type Error = A::Error;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_seq(self.seq)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct enum identifier ignored_any
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer that iterates over a map.
+pub struct MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+{
+ iter: iter::Fuse<I>,
+ value: Option<Second<I::Item>>,
+ count: usize,
+ lifetime: PhantomData<&'de ()>,
+ error: PhantomData<E>,
+}
+
+impl<'de, I, E> MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+{
+ /// Construct a new `MapDeserializer<I, E>`.
+ pub fn new(iter: I) -> Self {
+ MapDeserializer {
+ iter: iter.fuse(),
+ value: None,
+ count: 0,
+ lifetime: PhantomData,
+ error: PhantomData,
+ }
+ }
+}
+
+impl<'de, I, E> MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+ E: de::Error,
+{
+ /// Check for remaining elements after passing a `MapDeserializer` to
+ /// `Visitor::visit_map`.
+ pub fn end(self) -> Result<(), E> {
+ let remaining = self.iter.count();
+ if remaining == 0 {
+ Ok(())
+ } else {
+ // First argument is the number of elements in the data, second
+ // argument is the number of elements expected by the Deserialize.
+ Err(de::Error::invalid_length(
+ self.count + remaining,
+ &ExpectedInMap(self.count),
+ ))
+ }
+ }
+}
+
+impl<'de, I, E> MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+{
+ fn next_pair(&mut self) -> Option<(First<I::Item>, Second<I::Item>)> {
+ match self.iter.next() {
+ Some(kv) => {
+ self.count += 1;
+ Some(private::Pair::split(kv))
+ }
+ None => None,
+ }
+ }
+}
+
+impl<'de, I, E> de::Deserializer<'de> for MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+ First<I::Item>: IntoDeserializer<'de, E>,
+ Second<I::Item>: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let value = tri!(visitor.visit_map(&mut self));
+ tri!(self.end());
+ Ok(value)
+ }
+
+ fn deserialize_seq<V>(mut self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let value = tri!(visitor.visit_seq(&mut self));
+ tri!(self.end());
+ Ok(value)
+ }
+
+ fn deserialize_tuple<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let _ = len;
+ self.deserialize_seq(visitor)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct tuple_struct map
+ struct enum identifier ignored_any
+ }
+}
+
+impl<'de, I, E> de::MapAccess<'de> for MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+ First<I::Item>: IntoDeserializer<'de, E>,
+ Second<I::Item>: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ match self.next_pair() {
+ Some((key, value)) => {
+ self.value = Some(value);
+ seed.deserialize(key.into_deserializer()).map(Some)
+ }
+ None => Ok(None),
+ }
+ }
+
+ fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ let value = self.value.take();
+ // Panic because this indicates a bug in the program rather than an
+ // expected failure.
+ let value = value.expect("MapAccess::next_value called before next_key");
+ seed.deserialize(value.into_deserializer())
+ }
+
+ fn next_entry_seed<TK, TV>(
+ &mut self,
+ kseed: TK,
+ vseed: TV,
+ ) -> Result<Option<(TK::Value, TV::Value)>, Self::Error>
+ where
+ TK: de::DeserializeSeed<'de>,
+ TV: de::DeserializeSeed<'de>,
+ {
+ match self.next_pair() {
+ Some((key, value)) => {
+ let key = tri!(kseed.deserialize(key.into_deserializer()));
+ let value = tri!(vseed.deserialize(value.into_deserializer()));
+ Ok(Some((key, value)))
+ }
+ None => Ok(None),
+ }
+ }
+
+ fn size_hint(&self) -> Option<usize> {
+ size_hint::from_bounds(&self.iter)
+ }
+}
+
+impl<'de, I, E> de::SeqAccess<'de> for MapDeserializer<'de, I, E>
+where
+ I: Iterator,
+ I::Item: private::Pair,
+ First<I::Item>: IntoDeserializer<'de, E>,
+ Second<I::Item>: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ match self.next_pair() {
+ Some((k, v)) => {
+ let de = PairDeserializer(k, v, PhantomData);
+ seed.deserialize(de).map(Some)
+ }
+ None => Ok(None),
+ }
+ }
+
+ fn size_hint(&self) -> Option<usize> {
+ size_hint::from_bounds(&self.iter)
+ }
+}
+
+// Cannot #[derive(Clone)] because of the bound `Second<I::Item>: Clone`.
+impl<'de, I, E> Clone for MapDeserializer<'de, I, E>
+where
+ I: Iterator + Clone,
+ I::Item: private::Pair,
+ Second<I::Item>: Clone,
+{
+ fn clone(&self) -> Self {
+ MapDeserializer {
+ iter: self.iter.clone(),
+ value: self.value.clone(),
+ count: self.count,
+ lifetime: self.lifetime,
+ error: self.error,
+ }
+ }
+}
+
+impl<'de, I, E> Debug for MapDeserializer<'de, I, E>
+where
+ I: Iterator + Debug,
+ I::Item: private::Pair,
+ Second<I::Item>: Debug,
+{
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter
+ .debug_struct("MapDeserializer")
+ .field("iter", &self.iter)
+ .field("value", &self.value)
+ .field("count", &self.count)
+ .finish()
+ }
+}
+
+// Used in the `impl SeqAccess for MapDeserializer` to visit the map as a
+// sequence of pairs.
+struct PairDeserializer<A, B, E>(A, B, PhantomData<E>);
+
+impl<'de, A, B, E> de::Deserializer<'de> for PairDeserializer<A, B, E>
+where
+ A: IntoDeserializer<'de, E>,
+ B: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct tuple_struct map
+ struct enum identifier ignored_any
+ }
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ self.deserialize_seq(visitor)
+ }
+
+ fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ let mut pair_visitor = PairVisitor(Some(self.0), Some(self.1), PhantomData);
+ let pair = tri!(visitor.visit_seq(&mut pair_visitor));
+ if pair_visitor.1.is_none() {
+ Ok(pair)
+ } else {
+ let remaining = pair_visitor.size_hint().unwrap();
+ // First argument is the number of elements in the data, second
+ // argument is the number of elements expected by the Deserialize.
+ Err(de::Error::invalid_length(2, &ExpectedInSeq(2 - remaining)))
+ }
+ }
+
+ fn deserialize_tuple<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ if len == 2 {
+ self.deserialize_seq(visitor)
+ } else {
+ // First argument is the number of elements in the data, second
+ // argument is the number of elements expected by the Deserialize.
+ Err(de::Error::invalid_length(2, &ExpectedInSeq(len)))
+ }
+ }
+}
+
+struct PairVisitor<A, B, E>(Option<A>, Option<B>, PhantomData<E>);
+
+impl<'de, A, B, E> de::SeqAccess<'de> for PairVisitor<A, B, E>
+where
+ A: IntoDeserializer<'de, E>,
+ B: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Error = E;
+
+ fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ if let Some(k) = self.0.take() {
+ seed.deserialize(k.into_deserializer()).map(Some)
+ } else if let Some(v) = self.1.take() {
+ seed.deserialize(v.into_deserializer()).map(Some)
+ } else {
+ Ok(None)
+ }
+ }
+
+ fn size_hint(&self) -> Option<usize> {
+ if self.0.is_some() {
+ Some(2)
+ } else if self.1.is_some() {
+ Some(1)
+ } else {
+ Some(0)
+ }
+ }
+}
+
+struct ExpectedInMap(usize);
+
+impl Expected for ExpectedInMap {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ if self.0 == 1 {
+ write!(formatter, "1 element in map")
+ } else {
+ write!(formatter, "{} elements in map", self.0)
+ }
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg_attr(doc_cfg, doc(cfg(any(feature = "std", feature = "alloc"))))]
+impl<'de, K, V, E> IntoDeserializer<'de, E> for BTreeMap<K, V>
+where
+ K: IntoDeserializer<'de, E> + Eq + Ord,
+ V: IntoDeserializer<'de, E>,
+ E: de::Error,
+{
+ type Deserializer = MapDeserializer<'de, <Self as IntoIterator>::IntoIter, E>;
+
+ fn into_deserializer(self) -> Self::Deserializer {
+ MapDeserializer::new(self.into_iter())
+ }
+}
+
+#[cfg(feature = "std")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
+impl<'de, K, V, S, E> IntoDeserializer<'de, E> for HashMap<K, V, S>
+where
+ K: IntoDeserializer<'de, E> + Eq + Hash,
+ V: IntoDeserializer<'de, E>,
+ S: BuildHasher,
+ E: de::Error,
+{
+ type Deserializer = MapDeserializer<'de, <Self as IntoIterator>::IntoIter, E>;
+
+ fn into_deserializer(self) -> Self::Deserializer {
+ MapDeserializer::new(self.into_iter())
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding a `MapAccess`.
+#[derive(Clone, Debug)]
+pub struct MapAccessDeserializer<A> {
+ map: A,
+}
+
+impl<A> MapAccessDeserializer<A> {
+ /// Construct a new `MapAccessDeserializer<A>`.
+ pub fn new(map: A) -> Self {
+ MapAccessDeserializer { map }
+ }
+}
+
+impl<'de, A> de::Deserializer<'de> for MapAccessDeserializer<A>
+where
+ A: de::MapAccess<'de>,
+{
+ type Error = A::Error;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_map(self.map)
+ }
+
+ fn deserialize_enum<V>(
+ self,
+ _name: &str,
+ _variants: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_enum(self)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct identifier ignored_any
+ }
+}
+
+impl<'de, A> de::EnumAccess<'de> for MapAccessDeserializer<A>
+where
+ A: de::MapAccess<'de>,
+{
+ type Error = A::Error;
+ type Variant = private::MapAsEnum<A>;
+
+ fn variant_seed<T>(mut self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error>
+ where
+ T: de::DeserializeSeed<'de>,
+ {
+ match tri!(self.map.next_key_seed(seed)) {
+ Some(key) => Ok((key, private::map_as_enum(self.map))),
+ None => Err(de::Error::invalid_type(de::Unexpected::Map, &"enum")),
+ }
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+/// A deserializer holding an `EnumAccess`.
+#[derive(Clone, Debug)]
+pub struct EnumAccessDeserializer<A> {
+ access: A,
+}
+
+impl<A> EnumAccessDeserializer<A> {
+ /// Construct a new `EnumAccessDeserializer<A>`.
+ pub fn new(access: A) -> Self {
+ EnumAccessDeserializer { access }
+ }
+}
+
+impl<'de, A> de::Deserializer<'de> for EnumAccessDeserializer<A>
+where
+ A: de::EnumAccess<'de>,
+{
+ type Error = A::Error;
+
+ fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ visitor.visit_enum(self.access)
+ }
+
+ forward_to_deserialize_any! {
+ bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+ bytes byte_buf option unit unit_struct newtype_struct seq tuple
+ tuple_struct map struct enum identifier ignored_any
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+mod private {
+ use crate::lib::*;
+
+ use crate::de::{
+ self, DeserializeSeed, Deserializer, MapAccess, Unexpected, VariantAccess, Visitor,
+ };
+
+ pub struct UnitOnly<E> {
+ marker: PhantomData<E>,
+ }
+
+ pub fn unit_only<T, E>(t: T) -> (T, UnitOnly<E>) {
+ (
+ t,
+ UnitOnly {
+ marker: PhantomData,
+ },
+ )
+ }
+
+ impl<'de, E> de::VariantAccess<'de> for UnitOnly<E>
+ where
+ E: de::Error,
+ {
+ type Error = E;
+
+ fn unit_variant(self) -> Result<(), Self::Error> {
+ Ok(())
+ }
+
+ fn newtype_variant_seed<T>(self, _seed: T) -> Result<T::Value, Self::Error>
+ 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, Self::Error>
+ 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, Self::Error>
+ where
+ V: de::Visitor<'de>,
+ {
+ Err(de::Error::invalid_type(
+ Unexpected::UnitVariant,
+ &"struct variant",
+ ))
+ }
+ }
+
+ pub struct MapAsEnum<A> {
+ map: A,
+ }
+
+ pub fn map_as_enum<A>(map: A) -> MapAsEnum<A> {
+ MapAsEnum { map }
+ }
+
+ impl<'de, A> VariantAccess<'de> for MapAsEnum<A>
+ where
+ A: MapAccess<'de>,
+ {
+ type Error = A::Error;
+
+ fn unit_variant(mut self) -> Result<(), Self::Error> {
+ self.map.next_value()
+ }
+
+ fn newtype_variant_seed<T>(mut self, seed: T) -> Result<T::Value, Self::Error>
+ where
+ T: DeserializeSeed<'de>,
+ {
+ self.map.next_value_seed(seed)
+ }
+
+ fn tuple_variant<V>(mut self, len: usize, visitor: V) -> Result<V::Value, Self::Error>
+ where
+ V: Visitor<'de>,
+ {
+ self.map.next_value_seed(SeedTupleVariant { len, visitor })
+ }
+
+ fn struct_variant<V>(
+ mut self,
+ _fields: &'static [&'static str],
+ visitor: V,
+ ) -> Result<V::Value, Self::Error>
+ where
+ V: Visitor<'de>,
+ {
+ self.map.next_value_seed(SeedStructVariant { visitor })
+ }
+ }
+
+ struct SeedTupleVariant<V> {
+ len: usize,
+ visitor: V,
+ }
+
+ impl<'de, V> DeserializeSeed<'de> for SeedTupleVariant<V>
+ where
+ V: Visitor<'de>,
+ {
+ type Value = V::Value;
+
+ fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
+ where
+ D: Deserializer<'de>,
+ {
+ deserializer.deserialize_tuple(self.len, self.visitor)
+ }
+ }
+
+ struct SeedStructVariant<V> {
+ visitor: V,
+ }
+
+ impl<'de, V> DeserializeSeed<'de> for SeedStructVariant<V>
+ where
+ V: Visitor<'de>,
+ {
+ type Value = V::Value;
+
+ fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
+ where
+ D: Deserializer<'de>,
+ {
+ deserializer.deserialize_map(self.visitor)
+ }
+ }
+
+ /// Avoid having to restate the generic types on `MapDeserializer`. The
+ /// `Iterator::Item` contains enough information to figure out K and V.
+ pub trait Pair {
+ type First;
+ type Second;
+ fn split(self) -> (Self::First, Self::Second);
+ }
+
+ impl<A, B> Pair for (A, B) {
+ type First = A;
+ type Second = B;
+ fn split(self) -> (A, B) {
+ self
+ }
+ }
+
+ pub type First<T> = <T as Pair>::First;
+ pub type Second<T> = <T as Pair>::Second;
+}
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