Use captured identifiers in format strings.

This was stabilized in Rust 1.58.0: https://blog.rust-lang.org/2022/01/13/Rust-1.58.0.html

README.md

@@ -33,7 +33,7 @@ returns the value produced by the other process.
 
 RPC frameworks are a fundamental building block of most microservices-oriented
 architectures. Two well-known ones are [gRPC](http://www.grpc.io) and
-[Cap’n Proto](https://capnproto.org/).
+[Cap'n Proto](https://capnproto.org/).
 
 tarpc differentiates itself from other RPC frameworks by defining the schema in code,
 rather than in a separate language such as .proto. This means there's no separate compilation
@@ -128,7 +128,7 @@ impl World for HelloServer {
     type HelloFut = Ready<String>;
 
     fn hello(self, _: context::Context, name: String) -> Self::HelloFut {
-        future::ready(format!("Hello, {}!", name))
+        future::ready(format!("Hello, {name}!"))
     }
 }
 ```
@@ -155,7 +155,7 @@ async fn main() -> anyhow::Result<()> {
     // specifies a deadline and trace information which can be helpful in debugging requests.
     let hello = client.hello(context::current(), "Stim".to_string()).await?;
 
-    println!("{}", hello);
+    println!("{hello}");
 
     Ok(())
 }

example-service/src/server.rs

@@ -40,7 +40,7 @@ impl World for HelloServer {
         let sleep_time =
             Duration::from_millis(Uniform::new_inclusive(1, 10).sample(&mut thread_rng()));
         time::sleep(sleep_time).await;
-        format!("Hello, {}! You are connected from {}", name, self.0)
+        format!("Hello, {name}! You are connected from {}", self.0)
     }
 }
 

plugins/src/lib.rs

@@ -83,7 +83,7 @@ impl Parse for Service {
                     ident_errors,
                     syn::Error::new(
                         rpc.ident.span(),
-                        format!("method name conflicts with generated fn `{}::serve`", ident)
+                        format!("method name conflicts with generated fn `{ident}::serve`")
                     )
                 );
             }
@@ -270,7 +270,7 @@ pub fn service(attr: TokenStream, input: TokenStream) -> TokenStream {
     let methods = rpcs.iter().map(|rpc| &rpc.ident).collect::<Vec<_>>();
     let request_names = methods
         .iter()
-        .map(|m| format!("{}.{}", ident, m))
+        .map(|m| format!("{ident}.{m}"))
         .collect::<Vec<_>>();
 
     ServiceGenerator {
@@ -306,7 +306,7 @@ pub fn service(attr: TokenStream, input: TokenStream) -> TokenStream {
             .collect::<Vec<_>>(),
         future_types: &camel_case_fn_names
             .iter()
-            .map(|name| parse_str(&format!("{}Fut", name)).unwrap())
+            .map(|name| parse_str(&format!("{name}Fut")).unwrap())
             .collect::<Vec<_>>(),
         derive_serialize: derive_serialize.as_ref(),
     }
@@ -409,7 +409,7 @@ fn verify_types_were_provided(
         if !provided.iter().any(|typedecl| typedecl.ident == expected) {
             let mut e = syn::Error::new(
                 span,
-                format!("not all trait items implemented, missing: `{}`", expected),
+                format!("not all trait items implemented, missing: `{expected}`"),
             );
             let fn_span = method.sig.fn_token.span();
             e.extend(syn::Error::new(
@@ -479,7 +479,7 @@ impl<'a> ServiceGenerator<'a> {
                     ),
                     output,
                 )| {
-                    let ty_doc = format!("The response future returned by [`{}::{}`].", service_ident, ident);
+                    let ty_doc = format!("The response future returned by [`{service_ident}::{ident}`].");
                     quote! {
                         #[doc = #ty_doc]
                         type #future_type: std::future::Future<Output = #output>;

tarpc/examples/compression.rs

@@ -54,7 +54,7 @@ where
             if algorithm != CompressionAlgorithm::Deflate {
                 return Err(io::Error::new(
                     io::ErrorKind::InvalidData,
-                    format!("Compression algorithm {:?} not supported", algorithm),
+                    format!("Compression algorithm {algorithm:?} not supported"),
                 ));
             }
             let mut deflater = DeflateDecoder::new(payload.as_slice());
@@ -102,7 +102,7 @@ struct HelloServer;
 #[tarpc::server]
 impl World for HelloServer {
     async fn hello(self, _: context::Context, name: String) -> String {
-        format!("Hey, {}!", name)
+        format!("Hey, {name}!")
     }
 }
 

tarpc/examples/readme.rs

@@ -29,7 +29,7 @@ impl World for HelloServer {
     type HelloFut = Ready<String>;
 
     fn hello(self, _: context::Context, name: String) -> Self::HelloFut {
-        future::ready(format!("Hello, {}!", name))
+        future::ready(format!("Hello, {name}!"))
     }
 }
 
@@ -49,7 +49,7 @@ async fn main() -> anyhow::Result<()> {
     // specifies a deadline and trace information which can be helpful in debugging requests.
     let hello = client.hello(context::current(), "Stim".to_string()).await?;
 
-    println!("{}", hello);
+    println!("{hello}");
 
     Ok(())
 }

tarpc/src/lib.rs

@@ -132,7 +132,7 @@
 //!     type HelloFut = Ready<String>;
 //!
 //!     fn hello(self, _: context::Context, name: String) -> Self::HelloFut {
-//!         future::ready(format!("Hello, {}!", name))
+//!         future::ready(format!("Hello, {name}!"))
 //!     }
 //! }
 //! ```
@@ -168,7 +168,7 @@
 //! #     // an associated type representing the future output by the fn.
 //! #     type HelloFut = Ready<String>;
 //! #     fn hello(self, _: context::Context, name: String) -> Self::HelloFut {
-//! #         future::ready(format!("Hello, {}!", name))
+//! #         future::ready(format!("Hello, {name}!"))
 //! #     }
 //! # }
 //! # #[cfg(not(feature = "tokio1"))]
@@ -190,7 +190,7 @@
 //!     // specifies a deadline and trace information which can be helpful in debugging requests.
 //!     let hello = client.hello(context::current(), "Stim".to_string()).await?;
 //!
-//!     println!("{}", hello);
+//!     println!("{hello}");
 //!
 //!     Ok(())
 //! }
@@ -264,7 +264,7 @@ pub use tarpc_plugins::service;
 /// #[tarpc::server]
 /// impl World for HelloServer {
 ///     async fn hello(self, _: context::Context, name: String) -> String {
-///         format!("Hello, {}! You are connected from {:?}.", name, self.0)
+///         format!("Hello, {name}! You are connected from {:?}.", self.0)
 ///     }
 /// }
 /// ```
@@ -290,7 +290,7 @@ pub use tarpc_plugins::service;
 ///     fn hello(self, _: context::Context, name: String) -> Pin<Box<dyn Future<Output = String>
 ///     + Send>> {
 ///         Box::pin(async move {
-///             format!("Hello, {}! You are connected from {:?}.", name, self.0)
+///             format!("Hello, {name}! You are connected from {:?}.", self.0)
 ///         })
 ///     }
 /// }

tarpc/src/transport/channel.rs

@@ -181,7 +181,7 @@ mod tests {
                     future::ready(request.parse::<u64>().map_err(|_| {
                         io::Error::new(
                             io::ErrorKind::InvalidInput,
-                            format!("{:?} is not an int", request),
+                            format!("{request:?} is not an int"),
                         )
                     }))
                 }),

tarpc/src/util.rs

@@ -51,7 +51,7 @@ fn test_compact() {
 
     // Make usage ratio 25%
     for i in 0..896 {
-        map.insert(format!("k{}", i), "v");
+        map.insert(format!("k{i}"), "v");
     }
 
     map.compact(-1.0);

tarpc/tests/compile_fail/tarpc_server_missing_async.rs

@@ -7,8 +7,8 @@ struct HelloServer;
 
 #[tarpc::server]
 impl World for HelloServer {
-    fn hello(name: String) ->  String {
-        format!("Hello, {}!", name)
+    fn hello(name: String) -> String {
+        format!("Hello, {name}!", name)
     }
 }
 

tarpc/tests/compile_fail/tarpc_server_missing_async.stderr

@@ -7,5 +7,5 @@ error: not all trait items implemented, missing: `HelloFut`
 error: hint: `#[tarpc::server]` only rewrites async fns, and `fn hello` is not async
   --> $DIR/tarpc_server_missing_async.rs:10:5
    |
-10 |     fn hello(name: String) ->  String {
+10 |     fn hello(name: String) -> String {
    |     ^^

tarpc/tests/service_functional.rs

@@ -31,7 +31,7 @@ impl Service for Server {
     type HeyFut = Ready<String>;
 
     fn hey(self, _: context::Context, name: String) -> Self::HeyFut {
-        ready(format!("Hey, {}.", name))
+        ready(format!("Hey, {name}."))
     }
 }