Serialize and Deserialize for std::time::Duration

serde/src/de/impls.rs

@@ -53,6 +53,9 @@ use alloc::arc::Arc;
 #[cfg(all(feature = "unstable", feature = "alloc", not(feature = "std")))]
 use alloc::boxed::Box;
 
+#[cfg(feature = "std")]
+use std::time::Duration;
+
 #[cfg(feature = "unstable")]
 use core::nonzero::{NonZero, Zeroable};
 
@@ -982,6 +985,135 @@ impl<'a, T: ?Sized> Deserialize for Cow<'a, T> where T: ToOwned, T::Owned: Deser
 
 ///////////////////////////////////////////////////////////////////////////////
 
+// This is a cleaned-up version of the impl generated by:
+//
+//     #[derive(Deserialize)]
+//     #[serde(deny_unknown_fields)]
+//     struct Duration {
+//         secs: u64,
+//         nanos: u32,
+//     }
+#[cfg(feature = "std")]
+impl Deserialize for Duration {
+    fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
+        where D: Deserializer,
+    {
+        enum Field { Secs, Nanos };
+
+        impl Deserialize for Field {
+            fn deserialize<D>(deserializer: &mut D) -> Result<Field, D::Error>
+                where D: Deserializer,
+            {
+                struct FieldVisitor;
+
+                impl Visitor for FieldVisitor {
+                    type Value = Field;
+
+                    fn visit_usize<E>(&mut self, value: usize) -> Result<Field, E>
+                        where E: Error,
+                    {
+                        match value {
+                            0usize => Ok(Field::Secs),
+                            1usize => Ok(Field::Nanos),
+                            _ => Err(Error::invalid_value("expected a field")),
+                        }
+                    }
+
+                    fn visit_str<E>(&mut self, value: &str) -> Result<Field, E>
+                        where E: Error,
+                    {
+                        match value {
+                            "secs" => Ok(Field::Secs),
+                            "nanos" => Ok(Field::Nanos),
+                            _ => Err(Error::unknown_field(value)),
+                        }
+                    }
+
+                    fn visit_bytes<E>(&mut self, value: &[u8]) -> Result<Field, E>
+                        where E: Error,
+                    {
+                        match value {
+                            b"secs" => Ok(Field::Secs),
+                            b"nanos" => Ok(Field::Nanos),
+                            _ => {
+                                let value = String::from_utf8_lossy(value);
+                                Err(Error::unknown_field(&value))
+                            }
+                        }
+                    }
+                }
+
+                deserializer.deserialize_struct_field(FieldVisitor)
+            }
+        }
+
+        struct DurationVisitor;
+
+        impl Visitor for DurationVisitor {
+            type Value = Duration;
+
+            fn visit_seq<V>(&mut self, mut visitor: V) -> Result<Duration, V::Error>
+                where V: SeqVisitor,
+            {
+                let secs: u64 = match try!(visitor.visit()) {
+                    Some(value) => value,
+                    None => {
+                        try!(visitor.end());
+                        return Err(Error::invalid_length(0));
+                    }
+                };
+                let nanos: u32 = match try!(visitor.visit()) {
+                    Some(value) => value,
+                    None => {
+                        try!(visitor.end());
+                        return Err(Error::invalid_length(1));
+                    }
+                };
+                try!(visitor.end());
+                Ok(Duration::new(secs, nanos))
+            }
+
+            fn visit_map<V>(&mut self, mut visitor: V) -> Result<Duration, V::Error>
+                where V: MapVisitor,
+            {
+                let mut secs: Option<u64> = None;
+                let mut nanos: Option<u32> = None;
+                while let Some(key) = try!(visitor.visit_key::<Field>()) {
+                    match key {
+                        Field::Secs => {
+                            if secs.is_some() {
+                                return Err(<V::Error as Error>::duplicate_field("secs"));
+                            }
+                            secs = Some(try!(visitor.visit_value()));
+                        }
+                        Field::Nanos => {
+                            if nanos.is_some() {
+                                return Err(<V::Error as Error>::duplicate_field("nanos"));
+                            }
+                            nanos = Some(try!(visitor.visit_value()));
+                        }
+                    }
+                }
+                try!(visitor.end());
+                let secs = match secs {
+                    Some(secs) => secs,
+                    None => try!(visitor.missing_field("secs")),
+                };
+                let nanos = match nanos {
+                    Some(nanos) => nanos,
+                    None => try!(visitor.missing_field("nanos")),
+                };
+                Ok(Duration::new(secs, nanos))
+            }
+        }
+
+        const FIELDS: &'static [&'static str] = &["secs", "nanos"];
+        deserializer.deserialize_struct("Duration", FIELDS, DurationVisitor)
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
 #[cfg(feature = "unstable")]
 impl<T> Deserialize for NonZero<T> where T: Deserialize + PartialEq + Zeroable + Zero {
     fn deserialize<D>(deserializer: &mut D) -> Result<NonZero<T>, D::Error> where D: Deserializer {

serde/src/ser/impls.rs

@@ -50,6 +50,8 @@ use std::path;
 use std::rc::Rc;
 #[cfg(all(feature = "alloc", not(feature = "std")))]
 use alloc::rc::Rc;
+#[cfg(feature = "std")]
+use std::time::Duration;
 
 #[cfg(feature = "std")]
 use std::sync::Arc;
@@ -624,6 +626,20 @@ impl<T, E> Serialize for Result<T, E> where T: Serialize, E: Serialize {
 
 ///////////////////////////////////////////////////////////////////////////////
 
+#[cfg(feature = "std")]
+impl Serialize for Duration {
+    fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
+        where S: Serializer,
+    {
+        let mut state = try!(serializer.serialize_struct("Duration", 2));
+        try!(serializer.serialize_struct_elt(&mut state, "secs", self.as_secs()));
+        try!(serializer.serialize_struct_elt(&mut state, "nanos", self.subsec_nanos()));
+        serializer.serialize_struct_end(state)
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
 #[cfg(all(feature = "std", feature = "unstable"))]
 impl Serialize for net::IpAddr {
     fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>

testing/tests/test_de.rs

@@ -1,6 +1,7 @@
 use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
 use std::net;
 use std::path::PathBuf;
+use std::time::Duration;
 
 use serde::Deserialize;
 
@@ -745,6 +746,28 @@ declare_tests! {
             Token::SeqEnd,
         ],
     }
+    test_duration {
+        Duration::new(1, 2) => &[
+            Token::StructStart("Duration", 2),
+                Token::StructSep,
+                Token::Str("secs"),
+                Token::U64(1),
+
+                Token::StructSep,
+                Token::Str("nanos"),
+                Token::U32(2),
+            Token::StructEnd,
+        ],
+        Duration::new(1, 2) => &[
+            Token::SeqStart(Some(2)),
+                Token::SeqSep,
+                Token::I64(1),
+
+                Token::SeqSep,
+                Token::I64(2),
+            Token::SeqEnd,
+        ],
+    }
     test_net_ipv4addr {
         "1.2.3.4".parse::<net::Ipv4Addr>().unwrap() => &[Token::Str("1.2.3.4")],
     }

testing/tests/test_ser.rs

@@ -2,6 +2,7 @@ use std::collections::{BTreeMap, HashMap, HashSet};
 use std::net;
 use std::path::{Path, PathBuf};
 use std::str;
+use std::time::Duration;
 
 extern crate serde_test;
 use self::serde_test::{
@@ -324,6 +325,19 @@ declare_ser_tests! {
             Token::SeqEnd,
         ],
     }
+    test_duration {
+        Duration::new(1, 2) => &[
+            Token::StructStart("Duration", 2),
+                Token::StructSep,
+                Token::Str("secs"),
+                Token::U64(1),
+
+                Token::StructSep,
+                Token::Str("nanos"),
+                Token::U32(2),
+            Token::StructEnd,
+        ],
+    }
     test_net_ipv4addr {
         "1.2.3.4".parse::<net::Ipv4Addr>().unwrap() => &[Token::Str("1.2.3.4")],
     }