From 1153715149af423fee2b3cdf5f0442c82d559265 Mon Sep 17 00:00:00 2001
From: Nikolay Kim <fafhrd91@gmail.com>
Date: Tue, 5 Mar 2019 09:49:08 -0800
Subject: [PATCH] change generics order for Transform trait

---
 actix-service/src/and_then_apply.rs         |  8 ++---
 actix-service/src/fn_service.rs             |  7 ++--
 actix-service/src/fn_transform.rs           |  4 +--
 actix-service/src/lib.rs                    |  4 +--
 actix-service/src/transform.rs              | 36 ++++++++++-----------
 actix-service/src/transform_map_init_err.rs | 12 +++----
 actix-utils/src/inflight.rs                 |  2 +-
 actix-utils/src/order.rs                    |  2 +-
 actix-utils/src/timeout.rs                  |  2 +-
 9 files changed, 37 insertions(+), 40 deletions(-)

diff --git a/actix-service/src/and_then_apply.rs b/actix-service/src/and_then_apply.rs
index d24479bc..452f86d1 100644
--- a/actix-service/src/and_then_apply.rs
+++ b/actix-service/src/and_then_apply.rs
@@ -21,7 +21,7 @@ impl<T, A, B, BR> AndThenTransform<T, A, B, BR> {
     where
         A: NewService<AR, C>,
         B: NewService<BR, C, InitError = A::InitError>,
-        T: Transform<A::Response, B::Service, InitError = A::InitError>,
+        T: Transform<B::Service, A::Response, InitError = A::InitError>,
         T::Error: From<A::Error>,
     {
         Self {
@@ -52,7 +52,7 @@ impl<T, A, B, AR, BR, C> NewService<AR, C> for AndThenTransform<T, A, B, BR>
 where
     A: NewService<AR, C>,
     B: NewService<BR, C, InitError = A::InitError>,
-    T: Transform<A::Response, B::Service, InitError = A::InitError>,
+    T: Transform<B::Service, A::Response, InitError = A::InitError>,
     T::Error: From<A::Error>,
 {
     type Response = T::Response;
@@ -78,7 +78,7 @@ pub struct AndThenTransformFuture<T, A, B, AR, BR, C>
 where
     A: NewService<AR, C>,
     B: NewService<BR, C, InitError = A::InitError>,
-    T: Transform<A::Response, B::Service, InitError = A::InitError>,
+    T: Transform<B::Service, A::Response, InitError = A::InitError>,
     T::Error: From<A::Error>,
 {
     fut_a: A::Future,
@@ -93,7 +93,7 @@ impl<T, A, B, AR, BR, C> Future for AndThenTransformFuture<T, A, B, AR, BR, C>
 where
     A: NewService<AR, C>,
     B: NewService<BR, C, InitError = A::InitError>,
-    T: Transform<A::Response, B::Service, InitError = A::InitError>,
+    T: Transform<B::Service, A::Response, InitError = A::InitError>,
     T::Error: From<A::Error>,
 {
     type Item = AndThen<FromErr<A::Service, T::Error>, T::Transform>;
diff --git a/actix-service/src/fn_service.rs b/actix-service/src/fn_service.rs
index e32ad120..3d55b333 100644
--- a/actix-service/src/fn_service.rs
+++ b/actix-service/src/fn_service.rs
@@ -277,16 +277,13 @@ where
 
 #[cfg(test)]
 mod tests {
-    use futures::Future;
-
-    use super::*;
-    use crate::{IntoService, NewService, Service, ServiceExt};
+    use crate::{IntoService, Service, ServiceExt};
 
     #[test]
     fn test_fn_service() {
         let mut rt = actix_rt::Runtime::new().unwrap();
 
-        let srv = (|t: &str| -> Result<usize, ()> { Ok(1) }).into_service();
+        let srv = (|_t: &str| -> Result<usize, ()> { Ok(1) }).into_service();
         let mut srv = srv.and_then(|test: usize| Ok(test));
 
         let s = "HELLO".to_owned();
diff --git a/actix-service/src/fn_transform.rs b/actix-service/src/fn_transform.rs
index 24c56d2a..c3737f22 100644
--- a/actix-service/src/fn_transform.rs
+++ b/actix-service/src/fn_transform.rs
@@ -24,7 +24,7 @@ where
     }
 }
 
-impl<F, S, R, In, Out, Err> Transform<In, S> for FnTransform<F, S, R, In, Out, Err>
+impl<F, S, R, In, Out, Err> Transform<S, In> for FnTransform<F, S, R, In, Out, Err>
 where
     S: Service<R>,
     F: FnMut(In, &mut S) -> Out + Clone,
@@ -42,7 +42,7 @@ where
     }
 }
 
-impl<F, S, R, In, Out, Err> IntoTransform<FnTransform<F, S, R, In, Out, Err>, In, S> for F
+impl<F, S, R, In, Out, Err> IntoTransform<FnTransform<F, S, R, In, Out, Err>, S, In> for F
 where
     S: Service<R>,
     F: FnMut(In, &mut S) -> Out + Clone,
diff --git a/actix-service/src/lib.rs b/actix-service/src/lib.rs
index ca6f5b95..0bff0813 100644
--- a/actix-service/src/lib.rs
+++ b/actix-service/src/lib.rs
@@ -210,9 +210,9 @@ pub trait NewService<Request, Config = ()> {
     ) -> AndThenTransform<T, Self, B, Req>
     where
         Self: Sized,
-        T: Transform<Self::Response, B::Service, InitError = Self::InitError>,
+        T: Transform<B::Service, Self::Response, InitError = Self::InitError>,
         T::Error: From<Self::Error>,
-        T1: IntoTransform<T, Self::Response, B::Service>,
+        T1: IntoTransform<T, B::Service, Self::Response>,
         B: NewService<Req, Config, InitError = Self::InitError>,
         B1: IntoNewService<B, Req, Config>,
     {
diff --git a/actix-service/src/transform.rs b/actix-service/src/transform.rs
index 98944183..edba905e 100644
--- a/actix-service/src/transform.rs
+++ b/actix-service/src/transform.rs
@@ -12,7 +12,7 @@ use crate::{NewService, Service};
 ///
 /// * `S` is a wrapped service.
 /// * `R` requests handled by this transform service.
-pub trait Transform<R, S> {
+pub trait Transform<S, R> {
     /// Responses given by the service.
     type Response;
 
@@ -42,9 +42,9 @@ pub trait Transform<R, S> {
     }
 }
 
-impl<T, R, S> Transform<R, S> for Rc<T>
+impl<T, S, R> Transform<S, R> for Rc<T>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
 {
     type Response = T::Response;
     type Error = T::Error;
@@ -57,9 +57,9 @@ where
     }
 }
 
-impl<T, R, S> Transform<R, S> for Arc<T>
+impl<T, S, R> Transform<S, R> for Arc<T>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
 {
     type Response = T::Response;
     type Error = T::Error;
@@ -73,9 +73,9 @@ where
 }
 
 /// Trait for types that can be converted to a *transform service*
-pub trait IntoTransform<T, R, S>
+pub trait IntoTransform<T, S, R>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
 {
     /// Convert to a `TransformService`
     fn into_transform(self) -> T;
@@ -92,19 +92,19 @@ where
 
 /// `Apply` transform new service
 #[derive(Clone)]
-pub struct ApplyTransform<T, R, S, Req, Cfg> {
+pub struct ApplyTransform<T, S, R, Req, Cfg> {
     a: S,
     t: Rc<T>,
     _t: std::marker::PhantomData<(R, Req, Cfg)>,
 }
 
-impl<T, R, S, Req, Cfg> ApplyTransform<T, R, S, Req, Cfg>
+impl<T, S, R, Req, Cfg> ApplyTransform<T, S, R, Req, Cfg>
 where
     S: NewService<Req, Cfg>,
-    T: Transform<R, S::Service, Error = S::Error, InitError = S::InitError>,
+    T: Transform<S::Service, R, Error = S::Error, InitError = S::InitError>,
 {
     /// Create new `ApplyNewService` new service instance
-    pub fn new<F: IntoTransform<T, R, S::Service>>(t: F, a: S) -> Self {
+    pub fn new<F: IntoTransform<T, S::Service, R>>(t: F, a: S) -> Self {
         Self {
             a,
             t: Rc::new(t.into_transform()),
@@ -113,17 +113,17 @@ where
     }
 }
 
-impl<T, R, S, Req, Cfg> NewService<R, Cfg> for ApplyTransform<T, R, S, Req, Cfg>
+impl<T, S, R, Req, Cfg> NewService<R, Cfg> for ApplyTransform<T, S, R, Req, Cfg>
 where
     S: NewService<Req, Cfg>,
-    T: Transform<R, S::Service, Error = S::Error, InitError = S::InitError>,
+    T: Transform<S::Service, R, Error = S::Error, InitError = S::InitError>,
 {
     type Response = T::Response;
     type Error = T::Error;
 
     type Service = T::Transform;
     type InitError = T::InitError;
-    type Future = ApplyTransformFuture<T, R, S, Req, Cfg>;
+    type Future = ApplyTransformFuture<T, S, R, Req, Cfg>;
 
     fn new_service(&self, cfg: &Cfg) -> Self::Future {
         ApplyTransformFuture {
@@ -134,20 +134,20 @@ where
     }
 }
 
-pub struct ApplyTransformFuture<T, R, S, Req, Cfg>
+pub struct ApplyTransformFuture<T, S, R, Req, Cfg>
 where
     S: NewService<Req, Cfg>,
-    T: Transform<R, S::Service, Error = S::Error, InitError = S::InitError>,
+    T: Transform<S::Service, R, Error = S::Error, InitError = S::InitError>,
 {
     fut_a: S::Future,
     fut_t: Option<T::Future>,
     t_cell: Rc<T>,
 }
 
-impl<T, R, S, Req, Cfg> Future for ApplyTransformFuture<T, R, S, Req, Cfg>
+impl<T, S, R, Req, Cfg> Future for ApplyTransformFuture<T, S, R, Req, Cfg>
 where
     S: NewService<Req, Cfg>,
-    T: Transform<R, S::Service, Error = S::Error, InitError = S::InitError>,
+    T: Transform<S::Service, R, Error = S::Error, InitError = S::InitError>,
 {
     type Item = T::Transform;
     type Error = T::InitError;
diff --git a/actix-service/src/transform_map_init_err.rs b/actix-service/src/transform_map_init_err.rs
index 3655b6b3..48589ffc 100644
--- a/actix-service/src/transform_map_init_err.rs
+++ b/actix-service/src/transform_map_init_err.rs
@@ -18,7 +18,7 @@ impl<T, S, F, E> TransformMapInitErr<T, S, F, E> {
     /// Create new `MapInitErr` new transform instance
     pub fn new<R>(t: T, f: F) -> Self
     where
-        T: Transform<R, S>,
+        T: Transform<S, R>,
         F: Fn(T::InitError) -> E,
     {
         Self {
@@ -43,9 +43,9 @@ where
     }
 }
 
-impl<T, R, S, F, E> Transform<R, S> for TransformMapInitErr<T, S, F, E>
+impl<T, R, S, F, E> Transform<S, R> for TransformMapInitErr<T, S, F, E>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
     F: Fn(T::InitError) -> E + Clone,
 {
     type Response = T::Response;
@@ -62,7 +62,7 @@ where
 
 pub struct TransformMapInitErrFuture<T, R, S, F, E>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
     F: Fn(T::InitError) -> E,
 {
     fut: T::Future,
@@ -71,7 +71,7 @@ where
 
 impl<T, R, S, F, E> TransformMapInitErrFuture<T, R, S, F, E>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
     F: Fn(T::InitError) -> E,
 {
     fn new(fut: T::Future, f: F) -> Self {
@@ -81,7 +81,7 @@ where
 
 impl<T, R, S, F, E> Future for TransformMapInitErrFuture<T, R, S, F, E>
 where
-    T: Transform<R, S>,
+    T: Transform<S, R>,
     F: Fn(T::InitError) -> E + Clone,
 {
     type Item = T::Transform;
diff --git a/actix-utils/src/inflight.rs b/actix-utils/src/inflight.rs
index 82f425b3..1462e32a 100644
--- a/actix-utils/src/inflight.rs
+++ b/actix-utils/src/inflight.rs
@@ -24,7 +24,7 @@ impl Default for InFlight {
     }
 }
 
-impl<S: Service<R>, R> Transform<R, S> for InFlight {
+impl<S: Service<R>, R> Transform<S, R> for InFlight {
     type Response = S::Response;
     type Error = S::Error;
     type InitError = Void;
diff --git a/actix-utils/src/order.rs b/actix-utils/src/order.rs
index 288b4e4a..8b0e6b6e 100644
--- a/actix-utils/src/order.rs
+++ b/actix-utils/src/order.rs
@@ -74,7 +74,7 @@ impl<S> InOrder<S> {
     }
 }
 
-impl<S, R> Transform<R, S> for InOrder<S>
+impl<S, R> Transform<S, R> for InOrder<S>
 where
     S: Service<R>,
     S::Response: 'static,
diff --git a/actix-utils/src/timeout.rs b/actix-utils/src/timeout.rs
index 4493a112..10b90aa5 100644
--- a/actix-utils/src/timeout.rs
+++ b/actix-utils/src/timeout.rs
@@ -80,7 +80,7 @@ impl<E> Clone for Timeout<E> {
     }
 }
 
-impl<S, R, E> Transform<R, S> for Timeout<E>
+impl<S, R, E> Transform<S, R> for Timeout<E>
 where
     S: Service<R>,
 {