From f500db6e91d46a9f61a7e9775137deb2ba45fed2 Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Tue, 14 Feb 2017 17:36:50 -0800
Subject: [PATCH] Pair serialize_with and deserialize_with into one attribute

---
 serde_codegen_internals/src/attr.rs | 12 ++++++++++++
 test_suite/tests/test_gen.rs        | 18 +++++++++++++++---
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/serde_codegen_internals/src/attr.rs b/serde_codegen_internals/src/attr.rs
index 224bb939..2ed7bf42 100644
--- a/serde_codegen_internals/src/attr.rs
+++ b/serde_codegen_internals/src/attr.rs
@@ -453,6 +453,18 @@ impl Field {
                         }
                     }
 
+                    // Parse `#[serde(with="...")]`
+                    MetaItem(NameValue(ref name, ref lit)) if name == "with" => {
+                        if let Ok(path) = parse_lit_into_path(cx, name.as_ref(), lit) {
+                            let mut ser_path = path.clone();
+                            ser_path.segments.push("serialize".into());
+                            serialize_with.set(ser_path);
+                            let mut de_path = path;
+                            de_path.segments.push("deserialize".into());
+                            deserialize_with.set(de_path);
+                        }
+                    }
+
                     // Parse `#[serde(bound="D: Serialize")]`
                     MetaItem(NameValue(ref name, ref lit)) if name == "bound" => {
                         if let Ok(where_predicates) =
diff --git a/test_suite/tests/test_gen.rs b/test_suite/tests/test_gen.rs
index 2f53a00e..d008c0f2 100644
--- a/test_suite/tests/test_gen.rs
+++ b/test_suite/tests/test_gen.rs
@@ -30,6 +30,14 @@ fn test_gen() {
     }
     assert::<With<i32>>();
 
+    #[derive(Serialize, Deserialize)]
+    struct WithTogether<T> {
+        t: T,
+        #[serde(with="both_x")]
+        x: X,
+    }
+    assert::<WithTogether<i32>>();
+
     #[derive(Serialize, Deserialize)]
     struct WithRef<'a, T: 'a> {
         #[serde(skip_deserializing)]
@@ -307,16 +315,20 @@ trait DeserializeWith: Sized {
 }
 
 // Implements neither Serialize nor Deserialize
-struct X;
+pub struct X;
 
-fn ser_x<S: Serializer>(_: &X, _: S) -> StdResult<S::Ok, S::Error> {
+pub fn ser_x<S: Serializer>(_: &X, _: S) -> StdResult<S::Ok, S::Error> {
     unimplemented!()
 }
 
-fn de_x<D: Deserializer>(_: D) -> StdResult<X, D::Error> {
+pub fn de_x<D: Deserializer>(_: D) -> StdResult<X, D::Error> {
     unimplemented!()
 }
 
+mod both_x {
+    pub use super::{ser_x as serialize, de_x as deserialize};
+}
+
 impl SerializeWith for X {
     fn serialize_with<S: Serializer>(_: &Self, _: S) -> StdResult<S::Ok, S::Error> {
         unimplemented!()