add HasClient instance for HttpVersion

servant-client/src/Servant/Client.hs

@@ -203,6 +203,17 @@ instance (KnownSymbol sym, ToHttpApiData a, HasClient sublayout)
 
     where hname = symbolVal (Proxy :: Proxy sym)
 
+-- | Using a 'HttpVersion' combinator in your API doesn't affect the client
+-- functions.
+instance HasClient sublayout
+  => HasClient (HttpVersion :> sublayout) where
+
+  type Client (HttpVersion :> sublayout) =
+    Client sublayout
+
+  clientWithRoute Proxy =
+    clientWithRoute (Proxy :: Proxy sublayout)
+
 -- | If you use a 'QueryParam' in one of your endpoints in your API,
 -- the corresponding querying function will automatically take
 -- an additional argument of the type specified by your 'QueryParam',

servant/src/Servant/API/Internal/Test/ComprehensiveAPI.hs

@@ -14,7 +14,7 @@ type ComprehensiveAPI =
   Get '[JSON] Int :<|>
   Capture "foo" Int :> GET :<|>
   Header "foo" Int :> GET :<|>
--- HttpVersion :> GET :<|>
+  HttpVersion :> GET :<|>
   IsSecure :> GET :<|>
   QueryParam "foo" Int :> GET :<|>
   QueryParams "foo" Int :> GET :<|>