Add Serialize/Deserialize impls for Range{From,Full,To}

CC #796
CC #1466
CC #1713

serde/src/de/impls.rs

@@ -2258,9 +2258,9 @@ impl<'de> Deserialize<'de> for SystemTime {
 //
 //     #[derive(Deserialize)]
 //     #[serde(deny_unknown_fields)]
-//     struct Range {
+//     struct Range<Idx> {
-//         start: u64,
+//         start: Idx,
-//         end: u32,
+//         end: Idx,
 //     }
 impl<'de, Idx> Deserialize<'de> for Range<Idx>
 where
@@ -2434,6 +2434,316 @@ mod range {
 
 ////////////////////////////////////////////////////////////////////////////////
 
+// Similar to:
+//
+//     #[derive(Deserialize)]
+//     #[serde(deny_unknown_fields)]
+//     struct RangeFrom<Idx> {
+//         start: Idx,
+//     }
+impl<'de, Idx> Deserialize<'de> for RangeFrom<Idx>
+where
+    Idx: Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let start = try!(deserializer.deserialize_struct(
+            "RangeFrom",
+            range_from::FIELDS,
+            range_from::RangeFromVisitor {
+                expecting: "struct RangeFrom",
+                phantom: PhantomData,
+            },
+        ));
+        Ok(start..)
+    }
+}
+
+mod range_from {
+    use lib::*;
+
+    use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
+
+    pub const FIELDS: &'static [&'static str] = &["end"];
+
+    // If this were outside of the serde crate, it would just use:
+    //
+    //    #[derive(Deserialize)]
+    //    #[serde(field_identifier, rename_all = "lowercase")]
+    enum Field {
+        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("`end`")
+                }
+
+                fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
+                where
+                    E: Error,
+                {
+                    match value {
+                        "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"end" => Ok(Field::End),
+                        _ => {
+                            let value = ::__private::from_utf8_lossy(value);
+                            Err(Error::unknown_field(&*value, FIELDS))
+                        }
+                    }
+                }
+            }
+
+            deserializer.deserialize_identifier(FieldVisitor)
+        }
+    }
+
+    pub struct RangeFromVisitor<Idx> {
+        pub expecting: &'static str,
+        pub phantom: PhantomData<Idx>,
+    }
+
+    impl<'de, Idx> Visitor<'de> for RangeFromVisitor<Idx>
+    where
+        Idx: Deserialize<'de>,
+    {
+        type Value = 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 end: Idx = match try!(seq.next_element()) {
+                Some(value) => value,
+                None => {
+                    return Err(Error::invalid_length(0, &self));
+                }
+            };
+            Ok(end)
+        }
+
+        fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
+        where
+            A: MapAccess<'de>,
+        {
+            let mut end: Option<Idx> = None;
+            while let Some(key) = try!(map.next_key()) {
+                match key {
+                    Field::End => {
+                        if end.is_some() {
+                            return Err(<A::Error as Error>::duplicate_field("end"));
+                        }
+                        end = Some(try!(map.next_value()));
+                    }
+                }
+            }
+            let end = match end {
+                Some(end) => end,
+                None => return Err(<A::Error as Error>::missing_field("end")),
+            };
+            Ok(end)
+        }
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+// Similar to:
+//
+//     #[derive(Deserialize)]
+//     #[serde(deny_unknown_fields)]
+//     struct RangeTo<Idx> {
+//         start: Idx,
+//     }
+impl<'de, Idx> Deserialize<'de> for RangeTo<Idx>
+where
+    Idx: Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let end = try!(deserializer.deserialize_struct(
+            "RangeTo",
+            range_to::FIELDS,
+            range_to::RangeToVisitor {
+                expecting: "struct RangeTo",
+                phantom: PhantomData,
+            },
+        ));
+        Ok(..end)
+    }
+}
+
+mod range_to {
+    use lib::*;
+
+    use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
+
+    pub const FIELDS: &'static [&'static str] = &["start"];
+
+    // If this were outside of the serde crate, it would just use:
+    //
+    //    #[derive(Deserialize)]
+    //    #[serde(field_identifier, rename_all = "lowercase")]
+    enum Field {
+        Start,
+    }
+
+    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`")
+                }
+
+                fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
+                where
+                    E: Error,
+                {
+                    match value {
+                        "start" => Ok(Field::Start),
+                        _ => 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),
+                        _ => {
+                            let value = ::__private::from_utf8_lossy(value);
+                            Err(Error::unknown_field(&*value, FIELDS))
+                        }
+                    }
+                }
+            }
+
+            deserializer.deserialize_identifier(FieldVisitor)
+        }
+    }
+
+    pub struct RangeToVisitor<Idx> {
+        pub expecting: &'static str,
+        pub phantom: PhantomData<Idx>,
+    }
+
+    impl<'de, Idx> Visitor<'de> for RangeToVisitor<Idx>
+    where
+        Idx: Deserialize<'de>,
+    {
+        type Value = 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));
+                }
+            };
+            Ok(start)
+        }
+
+        fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
+        where
+            A: MapAccess<'de>,
+        {
+            let mut start: 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()));
+                    }
+                }
+            }
+            let start = match start {
+                Some(start) => start,
+                None => return Err(<A::Error as Error>::missing_field("start")),
+            };
+            Ok(start)
+        }
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+// Similar to:
+//
+//     #[derive(Deserialize)]
+//     #[serde(deny_unknown_fields)]
+//     struct RangeFull;
+impl<'de> Deserialize<'de> for RangeFull {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_unit_struct("RangeFull", RangeFullVisitor)
+    }
+}
+
+struct RangeFullVisitor;
+
+impl<'de> Visitor<'de> for RangeFullVisitor {
+    type Value = RangeFull;
+
+    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(..)
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 #[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))]
 impl<'de, T> Deserialize<'de> for Bound<T>
 where

serde/src/lib.rs

@@ -180,7 +180,7 @@ mod lib {
     pub use self::core::fmt::{self, Debug, Display};
     pub use self::core::marker::{self, PhantomData};
     pub use self::core::num::Wrapping;
-    pub use self::core::ops::Range;
+    pub use self::core::ops::{Range, RangeFrom, RangeFull, RangeTo};
     pub use self::core::option::{self, Option};
     pub use self::core::result::{self, Result};
 

serde/src/ser/impls.rs

@@ -257,6 +257,34 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
+impl<Idx> Serialize for RangeFrom<Idx>
+where
+    Idx: Serialize,
+{
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        use super::SerializeStruct;
+        let mut state = try!(serializer.serialize_struct("RangeFrom", 1));
+        try!(state.serialize_field("start", &self.start));
+        state.end()
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+impl Serialize for RangeFull {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        serializer.serialize_unit_struct("RangeFull")
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 #[cfg(not(no_range_inclusive))]
 impl<Idx> Serialize for RangeInclusive<Idx>
 where
@@ -276,6 +304,23 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
+impl<Idx> Serialize for RangeTo<Idx>
+where
+    Idx: Serialize,
+{
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        use super::SerializeStruct;
+        let mut state = try!(serializer.serialize_struct("RangeTo", 1));
+        try!(state.serialize_field("end", &self.end));
+        state.end()
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 #[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))]
 impl<T> Serialize for Bound<T>
 where