re-export serde (#330)

* re-export serde
* make serde re-export dependent on serde1 feature flag
* update missing_async compile test case

plugins/src/lib.rs

@@ -240,7 +240,10 @@ pub fn service(attr: TokenStream, input: TokenStream) -> TokenStream {
     let args: &[&[PatType]] = &rpcs.iter().map(|rpc| &*rpc.args).collect::<Vec<_>>();
     let response_fut_name = &format!("{}ResponseFut", ident.unraw());
     let derive_serialize = if derive_serde.0 {
-        Some(quote!(#[derive(serde::Serialize, serde::Deserialize)]))
+        Some(
+            quote! {#[derive(tarpc::serde::Serialize, tarpc::serde::Deserialize)]
+            #[serde(crate = "tarpc::serde")]},
+        )
     } else {
         None
     };

tarpc/src/lib.rs

@@ -3,7 +3,6 @@
 // Use of this source code is governed by an MIT-style
 // license that can be found in the LICENSE file or at
 // https://opensource.org/licenses/MIT.
-
 //! *Disclaimer*: This is not an official Google product.
 //!
 //! tarpc is an RPC framework for rust with a focus on ease of use. Defining a
@@ -204,6 +203,9 @@
 pub mod rpc;
 pub use rpc::*;
 
+#[cfg(feature = "serde1")]
+pub use serde;
+
 #[cfg(feature = "serde-transport")]
 #[cfg_attr(docsrs, doc(cfg(feature = "serde-transport")))]
 pub mod serde_transport;

tarpc/src/rpc.rs

@@ -55,7 +55,7 @@ pub enum ClientMessage<T> {
     Cancel {
         /// The trace context associates the message with a specific chain of causally-related actions,
         /// possibly orchestrated across many distributed systems.
-        #[cfg_attr(feature = "serde", serde(default))]
+        #[cfg_attr(feature = "serde1", serde(default))]
         trace_context: trace::Context,
         /// The ID of the request to cancel.
         request_id: u64,

tarpc/src/rpc/util.rs

@@ -10,8 +10,8 @@ use std::{
     time::{Duration, SystemTime},
 };
 
-#[cfg(feature = "serde")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+#[cfg(feature = "serde1")]
+#[cfg_attr(docsrs, doc(cfg(feature = "serde1")))]
 pub mod serde;
 
 /// Extension trait for [SystemTimes](SystemTime) in the future, i.e. deadlines.

tarpc/src/trace.rs

@@ -27,7 +27,7 @@ use std::{
 /// Consists of a span identifying an event, an optional parent span identifying a causal event
 /// that triggered the current span, and a trace with which all related spans are associated.
 #[derive(Debug, Default, PartialEq, Eq, Hash, Clone, Copy)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]
 pub struct Context {
     /// An identifier of the trace associated with the current context. A trace ID is typically
     /// created at a root span and passed along through all causal events.
@@ -47,12 +47,12 @@ pub struct Context {
 /// A 128-bit UUID identifying a trace. All spans caused by the same originating span share the
 /// same trace ID.
 #[derive(Debug, Default, PartialEq, Eq, Hash, Clone, Copy)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]
 pub struct TraceId(u128);
 
 /// A 64-bit identifier of a span within a trace. The identifier is unique within the span's trace.
 #[derive(Debug, Default, PartialEq, Eq, Hash, Clone, Copy)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]
 pub struct SpanId(u64);
 
 impl Context {

tarpc/tests/compile_fail/tarpc_server_missing_async.stderr

@@ -9,11 +9,3 @@ error: hint: `#[tarpc::server]` only rewrites async fns, and `fn hello` is not a
    |
 10 |     fn hello(name: String) ->  String {
    |     ^^
-
-error[E0433]: failed to resolve: use of undeclared type or module `serde`
- --> $DIR/tarpc_server_missing_async.rs:1:1
-  |
-1 | #[tarpc::service]
-  | ^^^^^^^^^^^^^^^^^ use of undeclared type or module `serde`
-  |
-  = note: this error originates in an attribute macro (in Nightly builds, run with -Z macro-backtrace for more info)