Make the serde support behave better

The previous implementation could produce illegal JSON when used
with serde_json.

This is a breaking change because we have to add a Clone bound on
the Deserialize impls.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "euclid"
-version = "0.6.8"
+version = "0.7.0"
 authors = ["The Servo Project Developers"]
 description = "Geometry primitives"
 documentation = "http://doc.servo.org/euclid/"

src/macros.rs

@@ -7,8 +7,38 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+macro_rules! deserialize {
+    (
+        { $field:ident, $($rest:tt)* }
+        $count:tt
+        { $($acc:tt)* }
+        $name:ident
+        $deserializer:ident
+        $T:ty
+    ) => (
+        deserialize!(
+            { $($rest)* }
+            (1 + $count)
+            { $($acc)* { $field $count } }
+            $name
+            $deserializer
+            $T)
+    );
+    (
+        {}
+        $total:tt
+        { $({ $field:ident $index:expr })+ }
+        $name:ident
+        $deserializer:ident
+        $T:ty
+    ) => ({
+        let values = try!(<[$T; $total]>::deserialize($deserializer));
+        Ok($name { $($field: values[$index].clone(),)+ })
+    })
+}
+
 macro_rules! define_matrix {
-    ($(#[$attr:meta])* pub struct $name:ident <T> { $(pub $field:ident: T,)+ }) => (
+    ($(#[$attr:meta])* pub struct $name:ident<T> { $(pub $field:ident: T,)+ }) => (
         $(#[$attr])*
         #[derive(Clone, Copy, Eq, Hash, PartialEq)]
         pub struct $name<T> {
@@ -21,23 +51,19 @@ macro_rules! define_matrix {
             }
         }
 
-        impl<T: ::serde::Deserialize> ::serde::Deserialize for $name<T> {
+        impl<T: Clone + ::serde::Deserialize> ::serde::Deserialize for $name<T> {
             fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
                 where D: ::serde::Deserializer
             {
-                $(let $field = try!(T::deserialize(deserializer));)+
-                Ok($name {
-                    $($field: $field,)+
-                })
+                deserialize!({ $($field,)+ } 0 {} $name deserializer T)
             }
         }
 
         impl<T: ::serde::Serialize> ::serde::Serialize for $name<T> {
             fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
                 where S: ::serde::Serializer
             {
-                $(try!(self.$field.serialize(serializer));)+
-                Ok(())
+                [$(&self.$field,)+].serialize(serializer)
             }
         }
     )

src/rect.rs

@@ -31,12 +31,11 @@ impl<T: HeapSizeOf> HeapSizeOf for Rect<T> {
     }
 }
 
-impl<T: Deserialize> Deserialize for Rect<T> {
+impl<T: Clone + Deserialize> Deserialize for Rect<T> {
     fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
         where D: Deserializer
     {
-        let origin = try!(Deserialize::deserialize(deserializer));
-        let size = try!(Deserialize::deserialize(deserializer));
+        let (origin, size) = try!(Deserialize::deserialize(deserializer));
         Ok(Rect {
             origin: origin,
             size: size,
@@ -48,9 +47,7 @@ impl<T: Serialize> Serialize for Rect<T> {
     fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
         where S: Serializer
     {
-        try!(self.origin.serialize(serializer));
-        try!(self.size.serialize(serializer));
-        Ok(())
+        (&self.origin, &self.size).serialize(serializer)
     }
 }
 

src/side_offsets.rs

@@ -10,6 +10,7 @@
 //! A group of side offsets, which correspond to top/left/bottom/right for borders, padding,
 //! and margins in CSS.
 
+#[cfg(feature = "unstable")]
 use heapsize::HeapSizeOf;
 use num::Zero;
 use std::ops::Add;