rt: Remove `threaded_scheduler()` and `basic_scheduler()` (#2876)

Co-authored-by: Alice Ryhl <alice@ryhl.io>
Co-authored-by: Carl Lerche <me@carllerche.com>

3 files changed, 35 insertions, 15 deletions

diff --git a/tokio/src/signal/registry.rs b/tokio/src/signal/registry.rs
index 9e55a5e6..5d6f608c 100644
--- a/tokio/src/signal/registry.rs
+++ b/tokio/src/signal/registry.rs
@@ -306,7 +306,7 @@ mod tests {
     }
 
     fn rt() -> Runtime {
-        runtime::Builder::new().basic_scheduler().build().unwrap()
+        runtime::Builder::new_current_thread().build().unwrap()
     }
 
     async fn collect(mut rx: crate::sync::mpsc::Receiver<()>) -> Vec<()> {
diff --git a/tokio/src/signal/unix/driver.rs b/tokio/src/signal/unix/driver.rs
index d0615312..d4a49783 100644
--- a/tokio/src/signal/unix/driver.rs
+++ b/tokio/src/signal/unix/driver.rs
@@ -1,9 +1,10 @@
+#![cfg_attr(not(feature = "rt-core"), allow(dead_code))]
+
 //! Signal driver
 
 use crate::io::driver::Driver as IoDriver;
 use crate::io::PollEvented;
 use crate::park::Park;
-use crate::runtime::context;
 use crate::signal::registry::globals;
 
 use mio::net::UnixStream;
@@ -165,17 +166,6 @@ impl Park for Driver {
 // ===== impl Handle =====
 
 impl Handle {
-    /// Returns a handle to the current driver
-    ///
-    /// # Panics
-    ///
-    /// This function panics if there is no current signal driver set.
-    pub(super) fn current() -> Self {
-        context::signal_handle().expect(
-            "there is no signal driver running, must be called from the context of Tokio runtime",
-        )
-    }
-
     pub(super) fn check_inner(&self) -> io::Result<()> {
         if self.inner.strong_count() > 0 {
             Ok(())
@@ -184,3 +174,34 @@ impl Handle {
         }
     }
 }
+
+cfg_rt_core! {
+    impl Handle {
+        /// Returns a handle to the current driver
+        ///
+        /// # Panics
+        ///
+        /// This function panics if there is no current signal driver set.
+        pub(super) fn current() -> Self {
+            crate::runtime::context::signal_handle().expect(
+                "there is no signal driver running, must be called from the context of Tokio runtime",
+            )
+        }
+    }
+}
+
+cfg_not_rt_core! {
+    impl Handle {
+        /// Returns a handle to the current driver
+        ///
+        /// # Panics
+        ///
+        /// This function panics if there is no current signal driver set.
+        pub(super) fn current() -> Self {
+            panic!(
+                "there is no signal driver running, must be called from the context of Tokio runtime or with\
+                `rt-core` enabled.",
+            )
+        }
+    }
+}
diff --git a/tokio/src/signal/windows.rs b/tokio/src/signal/windows.rs
index f638eed8..46271722 100644
--- a/tokio/src/signal/windows.rs
+++ b/tokio/src/signal/windows.rs
@@ -289,8 +289,7 @@ mod tests {
     }
 
     fn rt() -> Runtime {
-        crate::runtime::Builder::new()
-            .basic_scheduler()
+        crate::runtime::Builder::new_current_thread()
             .build()
             .unwrap()
     }