rt: simplify rt-* features (#2949)

tokio:

    merge rt-core and rt-util as rt
    rename rt-threaded to rt-multi-thread

tokio-util:

    rename rt-core to rt

Closes #2942

.github/workflows/ci.yml

@@ -110,7 +110,7 @@ jobs:
           rm -rf tokio/tests
 
       - name: miri
-        run: cargo miri test --features rt-core,rt-threaded,rt-util,sync task
+        run: cargo miri test --features rt,rt-multi-thread,sync task
         working-directory: tokio
 
   cross:

tests-build/Cargo.toml

@@ -7,7 +7,7 @@ publish = false
 
 [features]
 full = ["tokio/full"]
-rt-core = ["tokio/rt-core", "tokio/macros"]
+rt = ["tokio/rt", "tokio/macros"]
 
 [dependencies]
 tokio = { path = "../tokio", optional = true }

tests-build/tests/fail/macros_core_no_default.stderr

@@ -1,4 +1,4 @@
-error: The default runtime flavor is `multi_thread`, but the `rt-threaded` feature is disabled.
+error: The default runtime flavor is `multi_thread`, but the `rt-multi-thread` feature is disabled.
  --> $DIR/macros_core_no_default.rs:3:1
   |
 3 | #[tokio::main]

tests-build/tests/macros.rs

@@ -5,7 +5,7 @@ fn compile_fail_full() {
     #[cfg(feature = "full")]
     t.compile_fail("tests/fail/macros_invalid_input.rs");
 
-    #[cfg(all(feature = "rt-core", not(feature = "full")))]
+    #[cfg(all(feature = "rt", not(feature = "full")))]
     t.compile_fail("tests/fail/macros_core_no_default.rs");
 
     drop(t);

tests-integration/Cargo.toml

@@ -8,16 +8,16 @@ publish = false
 [features]
 full = [
     "macros",
-    "rt-core",
-    "rt-threaded",
+    "rt",
+    "rt-multi-thread",
 
     "tokio/full",
     "tokio-test"
 ]
 macros = ["tokio/macros"]
 sync = ["tokio/sync"]
-rt-core = ["tokio/rt-core"]
-rt-threaded = ["rt-core", "tokio/rt-threaded"]
+rt = ["tokio/rt"]
+rt-multi-thread = ["rt", "tokio/rt-multi-thread"]
 
 [dependencies]
 tokio = { path = "../tokio" }

tests-integration/tests/macros_main.rs

@@ -1,4 +1,4 @@
-#![cfg(all(feature = "macros", feature = "rt-core"))]
+#![cfg(all(feature = "macros", feature = "rt"))]
 
 #[tokio::main]
 async fn basic_main() -> usize {

tokio-macros/src/entry.rs

@@ -28,16 +28,16 @@ struct FinalConfig {
 }
 
 struct Configuration {
-    rt_threaded_available: bool,
+    rt_multi_thread_available: bool,
     default_flavor: RuntimeFlavor,
     flavor: Option<RuntimeFlavor>,
     worker_threads: Option<(usize, Span)>,
 }
 
 impl Configuration {
-    fn new(is_test: bool, rt_threaded: bool) -> Self {
+    fn new(is_test: bool, rt_multi_thread: bool) -> Self {
         Configuration {
-            rt_threaded_available: rt_threaded,
+            rt_multi_thread_available: rt_multi_thread,
             default_flavor: match is_test {
                 true => RuntimeFlavor::CurrentThread,
                 false => RuntimeFlavor::Threaded,
@@ -91,15 +91,15 @@ impl Configuration {
                 flavor,
                 worker_threads: None,
             }),
-            (Threaded, worker_threads) if self.rt_threaded_available => Ok(FinalConfig {
+            (Threaded, worker_threads) if self.rt_multi_thread_available => Ok(FinalConfig {
                 flavor,
                 worker_threads: worker_threads.map(|(val, _span)| val),
             }),
             (Threaded, _) => {
                 let msg = if self.flavor.is_none() {
-                    "The default runtime flavor is `multi_thread`, but the `rt-threaded` feature is disabled."
+                    "The default runtime flavor is `multi_thread`, but the `rt-multi-thread` feature is disabled."
                 } else {
-                    "The runtime flavor `multi_thread` requires the `rt-threaded` feature."
+                    "The runtime flavor `multi_thread` requires the `rt-multi-thread` feature."
                 };
                 Err(syn::Error::new(Span::call_site(), msg))
             }
@@ -138,7 +138,7 @@ fn parse_knobs(
     mut input: syn::ItemFn,
     args: syn::AttributeArgs,
     is_test: bool,
-    rt_threaded: bool,
+    rt_multi_thread: bool,
 ) -> Result<TokenStream, syn::Error> {
     let sig = &mut input.sig;
     let body = &input.block;
@@ -157,7 +157,7 @@ fn parse_knobs(
     } else {
         "tokio::main"
     };
-    let mut config = Configuration::new(is_test, rt_threaded);
+    let mut config = Configuration::new(is_test, rt_multi_thread);
 
     for arg in args {
         match arg {
@@ -256,7 +256,7 @@ fn parse_knobs(
 }
 
 #[cfg(not(test))] // Work around for rust-lang/rust#62127
-pub(crate) fn main(args: TokenStream, item: TokenStream, rt_threaded: bool) -> TokenStream {
+pub(crate) fn main(args: TokenStream, item: TokenStream, rt_multi_thread: bool) -> TokenStream {
     let input = syn::parse_macro_input!(item as syn::ItemFn);
     let args = syn::parse_macro_input!(args as syn::AttributeArgs);
 
@@ -267,10 +267,10 @@ pub(crate) fn main(args: TokenStream, item: TokenStream, rt_threaded: bool) -> T
             .into();
     }
 
-    parse_knobs(input, args, false, rt_threaded).unwrap_or_else(|e| e.to_compile_error().into())
+    parse_knobs(input, args, false, rt_multi_thread).unwrap_or_else(|e| e.to_compile_error().into())
 }
 
-pub(crate) fn test(args: TokenStream, item: TokenStream, rt_threaded: bool) -> TokenStream {
+pub(crate) fn test(args: TokenStream, item: TokenStream, rt_multi_thread: bool) -> TokenStream {
     let input = syn::parse_macro_input!(item as syn::ItemFn);
     let args = syn::parse_macro_input!(args as syn::AttributeArgs);
 
@@ -290,5 +290,5 @@ pub(crate) fn test(args: TokenStream, item: TokenStream, rt_threaded: bool) -> T
             .into();
     }
 
-    parse_knobs(input, args, true, rt_threaded).unwrap_or_else(|e| e.to_compile_error().into())
+    parse_knobs(input, args, true, rt_multi_thread).unwrap_or_else(|e| e.to_compile_error().into())
 }

tokio-macros/src/lib.rs

@@ -189,7 +189,7 @@ pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
 /// macro is expanded.
 #[proc_macro_attribute]
 #[cfg(not(test))] // Work around for rust-lang/rust#62127
-pub fn main_rt_core(args: TokenStream, item: TokenStream) -> TokenStream {
+pub fn main_rt(args: TokenStream, item: TokenStream) -> TokenStream {
     entry::main(args, item, false)
 }
 
@@ -252,33 +252,33 @@ pub fn test(args: TokenStream, item: TokenStream) -> TokenStream {
 /// tokio 0.2 crate available as `tokio` in the module where this
 /// macro is expanded.
 #[proc_macro_attribute]
-pub fn test_rt_core(args: TokenStream, item: TokenStream) -> TokenStream {
+pub fn test_rt(args: TokenStream, item: TokenStream) -> TokenStream {
     entry::test(args, item, false)
 }
 
 /// Always fails with the error message below.
 /// ```text
-/// The #[tokio::main] macro requires rt-core or rt-threaded.
+/// The #[tokio::main] macro requires rt or rt-multi-thread.
 /// ```
 #[proc_macro_attribute]
 pub fn main_fail(_args: TokenStream, _item: TokenStream) -> TokenStream {
     syn::Error::new(
         proc_macro2::Span::call_site(),
-        "The #[tokio::main] macro requires rt-core or rt-threaded.",
+        "The #[tokio::main] macro requires rt or rt-multi-thread.",
     )
     .to_compile_error()
     .into()
 }
 
 /// Always fails with the error message below.
 /// ```text
-/// The #[tokio::test] macro requires rt-core or rt-threaded.
+/// The #[tokio::test] macro requires rt or rt-multi-thread.
 /// ```
 #[proc_macro_attribute]
 pub fn test_fail(_args: TokenStream, _item: TokenStream) -> TokenStream {
     syn::Error::new(
         proc_macro2::Span::call_site(),
-        "The #[tokio::test] macro requires rt-core or rt-threaded.",
+        "The #[tokio::test] macro requires rt or rt-multi-thread.",
     )
     .to_compile_error()
     .into()

tokio-test/Cargo.toml

@@ -21,7 +21,7 @@ categories = ["asynchronous", "testing"]
 publish = false
 
 [dependencies]
-tokio = { version = "0.3.0", path = "../tokio", features = ["rt-core", "stream", "sync", "time", "test-util"] }
+tokio = { version = "0.3.0", path = "../tokio", features = ["rt", "stream", "sync", "time", "test-util"] }
 
 bytes = "0.5.0"
 futures-core = "0.3.0"

tokio-util/Cargo.toml

@@ -31,7 +31,7 @@ compat = ["futures-io",]
 codec = ["tokio/stream"]
 time = ["tokio/time","slab"]
 io = []
-rt-core = ["tokio/rt-core"]
+rt = ["tokio/rt"]
 
 [dependencies]
 tokio = { version = "0.3.0", path = "../tokio" }

tokio-util/src/cfg.rs

@@ -40,11 +40,11 @@ macro_rules! cfg_io {
     }
 }
 
-macro_rules! cfg_rt_core {
+macro_rules! cfg_rt {
     ($($item:item)*) => {
         $(
-            #[cfg(feature = "rt-core")]
-            #[cfg_attr(docsrs, doc(cfg(feature = "rt-core")))]
+            #[cfg(feature = "rt")]
+            #[cfg_attr(docsrs, doc(cfg(feature = "rt")))]
             $item
         )*
     }

tokio-util/src/lib.rs

@@ -47,7 +47,7 @@ cfg_io! {
     pub mod io;
 }
 
-cfg_rt_core! {
+cfg_rt! {
     pub mod context;
 }
 

tokio-util/tests/context.rs

@@ -1,4 +1,4 @@
-#![cfg(feature = "rt-core")]
+#![cfg(feature = "rt")]
 #![warn(rust_2018_idioms)]
 
 use tokio::runtime::Builder;

tokio/Cargo.toml

@@ -37,9 +37,8 @@ full = [
   "macros",
   "net",
   "process",
-  "rt-core",
-  "rt-util",
-  "rt-threaded",
+  "rt",
+  "rt-multi-thread",
   "signal",
   "stream",
   "sync",
@@ -71,11 +70,10 @@ process = [
   "winapi/threadpoollegacyapiset",
 ]
 # Includes basic task execution capabilities
-rt-core = ["slab"]
-rt-util = []
-rt-threaded = [
+rt = ["slab"]
+rt-multi-thread = [
   "num_cpus",
-  "rt-core",
+  "rt",
 ]
 signal = [
   "lazy_static",

tokio/src/blocking.rs

@@ -1,9 +1,9 @@
-cfg_rt_core! {
+cfg_rt! {
     pub(crate) use crate::runtime::spawn_blocking;
     pub(crate) use crate::task::JoinHandle;
 }
 
-cfg_not_rt_core! {
+cfg_not_rt! {
     use std::fmt;
     use std::future::Future;
     use std::pin::Pin;
@@ -15,7 +15,7 @@ cfg_not_rt_core! {
         R: Send + 'static,
     {
         assert_send_sync::<JoinHandle<std::cell::Cell<()>>>();
-        panic!("requires the `rt-core` Tokio feature flag")
+        panic!("requires the `rt` Tokio feature flag")
 
     }
 

tokio/src/coop.rs

@@ -83,7 +83,7 @@ impl Budget {
     }
 }
 
-cfg_rt_threaded! {
+cfg_rt_multi_thread! {
     impl Budget {
         fn has_remaining(self) -> bool {
             self.0.map(|budget| budget > 0).unwrap_or(true)
@@ -122,7 +122,7 @@ fn with_budget<R>(budget: Budget, f: impl FnOnce() -> R) -> R {
     })
 }
 
-cfg_rt_threaded! {
+cfg_rt_multi_thread! {
     /// Set the current task's budget
     pub(crate) fn set(budget: Budget) {
         CURRENT.with(|cell| cell.set(budget))
@@ -134,7 +134,7 @@ cfg_rt_threaded! {
     }
 }
 
-cfg_rt_core! {
+cfg_rt! {
     /// Forcibly remove the budgeting constraints early.
     ///
     /// Returns the remaining budget

tokio/src/future/block_on.rs

@@ -1,13 +1,13 @@
 use std::future::Future;
 
-cfg_rt_core! {
+cfg_rt! {
     pub(crate) fn block_on<F: Future>(f: F) -> F::Output {
         let mut e = crate::runtime::enter::enter(false);
         e.block_on(f).unwrap()
     }
 }
 
-cfg_not_rt_core! {
+cfg_not_rt! {
     pub(crate) fn block_on<F: Future>(f: F) -> F::Output {
         let mut park = crate::park::thread::CachedParkThread::new();
         park.block_on(f).unwrap()

tokio/src/io/driver/mod.rs

@@ -1,4 +1,4 @@
-#![cfg_attr(not(feature = "rt-core"), allow(dead_code))]
+#![cfg_attr(not(feature = "rt"), allow(dead_code))]
 
 mod ready;
 use ready::Ready;
@@ -219,13 +219,13 @@ impl fmt::Debug for Driver {
 
 // ===== impl Handle =====
 
-cfg_rt_core! {
+cfg_rt! {
     impl Handle {
         /// Returns a handle to the current reactor
         ///
         /// # Panics
         ///
-        /// This function panics if there is no current reactor set and `rt-core` feature
+        /// This function panics if there is no current reactor set and `rt` feature
         /// flag is not enabled.
         pub(super) fn current() -> Self {
             crate::runtime::context::io_handle()
@@ -234,16 +234,16 @@ cfg_rt_core! {
     }
 }
 
-cfg_not_rt_core! {
+cfg_not_rt! {
     impl Handle {
         /// Returns a handle to the current reactor
         ///
         /// # Panics
         ///
-        /// This function panics if there is no current reactor set, or if the `rt-core`
+        /// This function panics if there is no current reactor set, or if the `rt`
         /// feature flag is not enabled.
         pub(super) fn current() -> Self {
-            panic!("there is no reactor running, must be called from the context of Tokio runtime with `rt-core` enabled.")
+            panic!("there is no reactor running, must be called from the context of Tokio runtime with `rt` enabled.")
         }
     }
 }