galvyn-core 0.5.0

//! Deserializes a single string into some `T` using `.parse()`

use std::marker::PhantomData;
use std::str::FromStr;

use serde::de::Error;
use serde::de::IntoDeserializer;
use serde::de::Visitor;

/// Deserializes a single string into some `T` using `.parse()`
///
/// (To be more precise, the string is converted into the intermediate type requested by `T`'s
/// `Deserialize` implementation using its `FromStr` implementation)
///
/// This has one notable **exception**:
/// `bool` supports `"true"`, `"yes"`, `"y"` and `"1"` (and the associated negations).
pub struct StringParseDeserializer<E = serde::de::value::Error> {
    string: String,
    _marker: PhantomData<E>,
}

impl StringParseDeserializer {
    /// Constructs a new `StringParseDeserializer`
    pub fn new(string: String) -> Self {
        Self {
            string,
            _marker: PhantomData,
        }
    }
}

impl<'de, E> IntoDeserializer<'de, E> for StringParseDeserializer<E>
where
    E: Error,
{
    type Deserializer = Self;

    fn into_deserializer(self) -> Self::Deserializer {
        self
    }
}

impl<E> StringParseDeserializer<E>
where
    E: Error,
{
    fn deserialize_parse<'de, V, T>(
        self,
        visitor: V,
        visitor_fn: impl Fn(V, T) -> Result<V::Value, E>,
    ) -> Result<V::Value, E>
    where
        V: Visitor<'de>,
        T: FromStr,
    {
        match self.string.parse() {
            Ok(value) => visitor_fn(visitor, value),
            Err(_) => visitor.visit_string(self.string),
        }
    }
}

impl<'de, E> serde::de::Deserializer<'de> for StringParseDeserializer<E>
where
    E: Error,
{
    type Error = E;

    fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        match self.string.as_str() {
            "true" | "1" | "yes" | "y" => visitor.visit_bool(true),
            "false" | "0" | "no" | "n" => visitor.visit_bool(false),
            _ => visitor.visit_string(self.string),
        }
    }

    fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_i8)
    }

    fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_i16)
    }

    fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_i32)
    }

    fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_i64)
    }

    fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_u8)
    }

    fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_u16)
    }

    fn deserialize_u32<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_u32)
    }

    fn deserialize_u64<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_u64)
    }

    fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_f32)
    }

    fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_f64)
    }

    fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        self.deserialize_parse(visitor, Visitor::visit_char)
    }

    fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_some(self)
    }

    fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_unit_struct<V>(
        self,
        _name: &'static str,
        visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_newtype_struct<V>(
        self,
        _name: &'static str,
        visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_newtype_struct(self)
    }

    fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_tuple<V>(self, _len: usize, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_tuple_struct<V>(
        self,
        _name: &'static str,
        _len: usize,
        visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_struct<V>(
        self,
        _name: &'static str,
        _fields: &'static [&'static str],
        visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_enum<V>(
        self,
        _name: &'static str,
        _variants: &'static [&'static str],
        visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }

    fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: Visitor<'de>,
    {
        visitor.visit_string(self.string)
    }
}