diff options
Diffstat (limited to 'third_party/rust/serde_with/src/with_prefix.rs')
| -rw-r--r-- | third_party/rust/serde_with/src/with_prefix.rs | 612 |
1 files changed, 612 insertions, 0 deletions
diff --git a/third_party/rust/serde_with/src/with_prefix.rs b/third_party/rust/serde_with/src/with_prefix.rs new file mode 100644 index 0000000000..b4b483c983 --- /dev/null +++ b/third_party/rust/serde_with/src/with_prefix.rs @@ -0,0 +1,612 @@ +use alloc::string::String; +use core::fmt; +use serde::{ + de::{self, DeserializeSeed, Deserializer, IgnoredAny, IntoDeserializer, MapAccess, Visitor}, + forward_to_deserialize_any, + ser::{self, Impossible, Serialize, SerializeMap, SerializeStruct, Serializer}, +}; + +/// Serialize with an added prefix on every field name and deserialize by +/// trimming away the prefix. +/// +/// You can set the visibility of the generated module by prefixing the module name with a module visibility. +/// `with_prefix!(pub(crate) prefix_foo "foo_");` creates a module with `pub(crate)` visibility. +/// The visibility is optional and by default `pub(self)`, i.e., private visibility is assumed. +/// +/// **Note:** Use of this macro is incompatible with applying the [`deny_unknown_fields`] attribute +/// on the container. +/// While deserializing, it will always warn about unknown fields, even though they are processed +/// by the `with_prefix` wrapper. +/// More details can be found in [this issue][issue-with_prefix-deny_unknown_fields]. +/// +/// # Example +/// +/// The [Challonge REST API] likes to use prefixes to group related fields. In +/// simplified form, their JSON may resemble the following: +/// +/// [Challonge REST API]: https://api.challonge.com/v1/documents/matches/show +/// +/// ```json +/// { +/// "player1_name": "name1", +/// "player1_votes": 1, +/// "player2_name": "name2", +/// "player2_votes": 2 +/// } +/// ``` +/// +/// In Rust, we would ideally like to model this data as a pair of `Player` +/// structs, rather than repeating the fields of `Player` for each prefix. +/// +/// ```rust +/// # #[allow(dead_code)] +/// struct Match { +/// player1: Player, +/// player2: Player, +/// } +/// +/// # #[allow(dead_code)] +/// struct Player { +/// name: String, +/// votes: u64, +/// } +/// ``` +/// +/// This `with_prefix!` macro produces an adapter that adds a prefix onto field +/// names during serialization and trims away the prefix during deserialization. +/// An implementation of the Challonge API would use `with_prefix!` like this: +/// +/// ```rust +/// use serde::{Deserialize, Serialize}; +/// use serde_with::with_prefix; +/// +/// #[derive(Serialize, Deserialize)] +/// struct Match { +/// #[serde(flatten, with = "prefix_player1")] +/// player1: Player, +/// #[serde(flatten, with = "prefix_player2")] +/// player2: Player, +/// } +/// +/// #[derive(Serialize, Deserialize)] +/// struct Player { +/// name: String, +/// votes: u64, +/// } +/// +/// with_prefix!(prefix_player1 "player1_"); +/// // You can also set the visibility of the generated prefix module, the default is private. +/// with_prefix!(pub prefix_player2 "player2_"); +/// # +/// # const EXPECTED: &str = r#"{ +/// # "player1_name": "name1", +/// # "player1_votes": 1, +/// # "player2_name": "name2", +/// # "player2_votes": 2 +/// # }"#; +/// +/// fn main() { +/// let m = Match { +/// player1: Player { +/// name: "name1".to_owned(), +/// votes: 1, +/// }, +/// player2: Player { +/// name: "name2".to_owned(), +/// votes: 2, +/// }, +/// }; +/// +/// let j = serde_json::to_string_pretty(&m).unwrap(); +/// println!("{}", j); +/// # +/// # assert_eq!(j, EXPECTED); +/// } +/// ``` +/// +/// [`deny_unknown_fields`]: https://serde.rs/container-attrs.html#deny_unknown_fields +/// [issue-with_prefix-deny_unknown_fields]: https://github.com/jonasbb/serde_with/issues/57 +#[macro_export] +macro_rules! with_prefix { + ($module:ident $prefix:expr) => {$crate::with_prefix!(pub(self) $module $prefix);}; + ($vis:vis $module:ident $prefix:expr) => { + $vis mod $module { + use $crate::serde::{Deserialize, Deserializer, Serialize, Serializer}; + use $crate::with_prefix::WithPrefix; + + #[allow(dead_code)] + pub fn serialize<T, S>(object: &T, serializer: S) -> ::std::result::Result<S::Ok, S::Error> + where + T: Serialize, + S: Serializer, + { + object.serialize(WithPrefix { + delegate: serializer, + prefix: $prefix, + }) + } + + #[allow(dead_code)] + pub fn deserialize<'de, T, D>(deserializer: D) -> ::std::result::Result<T, D::Error> + where + T: Deserialize<'de>, + D: Deserializer<'de>, + { + T::deserialize(WithPrefix { + delegate: deserializer, + prefix: $prefix, + }) + } + } + }; +} + +#[allow(missing_debug_implementations)] +pub struct WithPrefix<'a, T> { + pub delegate: T, + pub prefix: &'a str, +} + +impl<'a, T> Serialize for WithPrefix<'a, T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.delegate.serialize(WithPrefix { + delegate: serializer, + prefix: self.prefix, + }) + } +} + +impl<'a, S> Serializer for WithPrefix<'a, S> +where + S: Serializer, +{ + type Ok = S::Ok; + type Error = S::Error; + type SerializeSeq = Impossible<Self::Ok, Self::Error>; + type SerializeTuple = Impossible<Self::Ok, Self::Error>; + type SerializeTupleStruct = Impossible<Self::Ok, Self::Error>; + type SerializeTupleVariant = Impossible<Self::Ok, Self::Error>; + type SerializeMap = WithPrefix<'a, S::SerializeMap>; + type SerializeStruct = WithPrefix<'a, S::SerializeMap>; + type SerializeStructVariant = Impossible<Self::Ok, Self::Error>; + + fn serialize_bool(self, _v: bool) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_i8(self, _v: i8) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_i16(self, _v: i16) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_i32(self, _v: i32) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_i64(self, _v: i64) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_u8(self, _v: u8) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_u16(self, _v: u16) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_u32(self, _v: u32) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_u64(self, _v: u64) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_f32(self, _v: f32) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_f64(self, _v: f64) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_char(self, _v: char) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_str(self, v: &str) -> Result<Self::Ok, Self::Error> { + self.delegate + .collect_str(&format_args!("{}{}", self.prefix, v)) + } + + fn serialize_bytes(self, _v: &[u8]) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_none(self) -> Result<Self::Ok, Self::Error> { + self.delegate.serialize_none() + } + + fn serialize_some<T>(self, value: &T) -> Result<Self::Ok, Self::Error> + where + T: ?Sized + Serialize, + { + self.delegate.serialize_some(&WithPrefix { + delegate: value, + prefix: self.prefix, + }) + } + + fn serialize_unit(self) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_unit_variant( + self, + _name: &'static str, + _variant_index: u32, + variant: &'static str, + ) -> Result<Self::Ok, Self::Error> { + self.serialize_str(variant) + } + + fn serialize_newtype_struct<T>( + self, + _name: &'static str, + _value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: ?Sized + Serialize, + { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_newtype_variant<T>( + self, + _name: &'static str, + _variant_index: u32, + _variant: &'static str, + _value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: ?Sized + Serialize, + { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_tuple_struct( + self, + _name: &'static str, + _len: usize, + ) -> Result<Self::SerializeTupleStruct, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_tuple_variant( + self, + _name: &'static str, + _variant_index: u32, + _variant: &'static str, + _len: usize, + ) -> Result<Self::SerializeTupleVariant, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } + + fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> { + Ok(WithPrefix { + delegate: self.delegate.serialize_map(len)?, + prefix: self.prefix, + }) + } + + fn serialize_struct( + self, + _name: &'static str, + len: usize, + ) -> Result<Self::SerializeStruct, Self::Error> { + self.serialize_map(Some(len)) + } + + fn serialize_struct_variant( + self, + _name: &'static str, + _variant_index: u32, + _variant: &'static str, + _len: usize, + ) -> Result<Self::SerializeStructVariant, Self::Error> { + Err(ser::Error::custom("wrong type for with_prefix")) + } +} + +impl<'a, S> SerializeMap for WithPrefix<'a, S> +where + S: SerializeMap, +{ + type Ok = S::Ok; + type Error = S::Error; + + fn serialize_key<T>(&mut self, key: &T) -> Result<(), Self::Error> + where + T: ?Sized + Serialize, + { + self.delegate.serialize_key(&WithPrefix { + delegate: key, + prefix: self.prefix, + }) + } + + fn serialize_value<T>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: ?Sized + Serialize, + { + self.delegate.serialize_value(value) + } + + fn serialize_entry<K, V>(&mut self, key: &K, value: &V) -> Result<(), Self::Error> + where + K: ?Sized + Serialize, + V: ?Sized + Serialize, + { + self.delegate.serialize_entry( + &WithPrefix { + delegate: key, + prefix: self.prefix, + }, + value, + ) + } + + fn end(self) -> Result<Self::Ok, Self::Error> { + self.delegate.end() + } +} + +impl<'a, S> SerializeStruct for WithPrefix<'a, S> +where + S: SerializeMap, +{ + type Ok = S::Ok; + type Error = S::Error; + + fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<(), Self::Error> + where + T: ?Sized + Serialize, + { + let mut prefixed_key = String::with_capacity(self.prefix.len() + key.len()); + prefixed_key.push_str(self.prefix); + prefixed_key.push_str(key); + self.delegate.serialize_entry(&prefixed_key, value) + } + + fn end(self) -> Result<Self::Ok, Self::Error> { + self.delegate.end() + } +} + +impl<'de, 'a, T> DeserializeSeed<'de> for WithPrefix<'a, T> +where + T: DeserializeSeed<'de>, +{ + type Value = T::Value; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + self.delegate.deserialize(WithPrefix { + delegate: deserializer, + prefix: self.prefix, + }) + } +} + +impl<'de, 'a, D> Deserializer<'de> for WithPrefix<'a, D> +where + D: Deserializer<'de>, +{ + type Error = D::Error; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.delegate.deserialize_map(WithPrefix { + delegate: visitor, + prefix: self.prefix, + }) + } + + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.delegate.deserialize_any(WithPrefixOption { + first_key: None, + delegate: visitor, + prefix: self.prefix, + }) + } + + fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.delegate.deserialize_identifier(WithPrefix { + delegate: visitor, + prefix: self.prefix, + }) + } + + 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 ignored_any + } +} + +impl<'de, 'a, V> Visitor<'de> for WithPrefix<'a, V> +where + V: Visitor<'de>, +{ + type Value = V::Value; + + fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { + self.delegate.expecting(formatter) + } + + fn visit_map<A>(self, map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + self.delegate.visit_map(WithPrefix { + delegate: map, + prefix: self.prefix, + }) + } +} + +impl<'de, 'a, A> MapAccess<'de> for WithPrefix<'a, A> +where + A: MapAccess<'de>, +{ + type Error = A::Error; + + fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Self::Error> + where + K: DeserializeSeed<'de>, + { + while let Some(s) = self.delegate.next_key::<String>()? { + if let Some(without_prefix) = s.strip_prefix(self.prefix) { + return seed + .deserialize(without_prefix.into_deserializer()) + .map(Some); + } + self.delegate.next_value::<IgnoredAny>()?; + } + Ok(None) + } + + fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Self::Error> + where + V: DeserializeSeed<'de>, + { + self.delegate.next_value_seed(seed) + } +} + +#[allow(missing_debug_implementations)] +pub struct WithPrefixOption<'a, T> { + first_key: Option<String>, + delegate: T, + prefix: &'a str, +} + +impl<'de, 'a, V> Visitor<'de> for WithPrefixOption<'a, V> +where + V: Visitor<'de>, +{ + type Value = V::Value; + + fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { + self.delegate.expecting(formatter) + } + + fn visit_unit<E>(self) -> Result<Self::Value, E> + where + E: de::Error, + { + self.delegate.visit_none() + } + + fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + while let Some(s) = map.next_key::<String>()? { + if s.starts_with(self.prefix) { + return self.delegate.visit_some(WithPrefixOption { + first_key: Some(s), + delegate: map, + prefix: self.prefix, + }); + } + map.next_value::<IgnoredAny>()?; + } + self.delegate.visit_none() + } +} + +impl<'de, 'a, A> Deserializer<'de> for WithPrefixOption<'a, A> +where + A: MapAccess<'de>, +{ + type Error = A::Error; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_map(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 enum identifier ignored_any + } +} + +impl<'de, 'a, A> MapAccess<'de> for WithPrefixOption<'a, A> +where + A: MapAccess<'de>, +{ + type Error = A::Error; + + fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Self::Error> + where + K: DeserializeSeed<'de>, + { + if let Some(s) = self.first_key.take() { + let without_prefix = s[self.prefix.len()..].into_deserializer(); + return seed.deserialize(without_prefix).map(Some); + } + while let Some(s) = self.delegate.next_key::<String>()? { + if let Some(without_prefix) = s.strip_prefix(self.prefix) { + return seed + .deserialize(without_prefix.into_deserializer()) + .map(Some); + } + self.delegate.next_value::<IgnoredAny>()?; + } + Ok(None) + } + + fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Self::Error> + where + V: DeserializeSeed<'de>, + { + self.delegate.next_value_seed(seed) + } +} |