From 3e6f69885cbcca4d9516d50f958c95a237e75ce8 Mon Sep 17 00:00:00 2001
From: Rob Ede <robjtede@icloud.com>
Date: Sun, 31 Jan 2021 04:43:35 +0000
Subject: [PATCH] remove arbiter TLS item storage

---
 actix-rt/src/arbiter.rs | 61 -----------------------------------------
 actix-rt/tests/tests.rs | 29 --------------------
 2 files changed, 90 deletions(-)

diff --git a/actix-rt/src/arbiter.rs b/actix-rt/src/arbiter.rs
index 44e34b5d..a3cb5272 100644
--- a/actix-rt/src/arbiter.rs
+++ b/actix-rt/src/arbiter.rs
@@ -1,7 +1,5 @@
 use std::{
-    any::{Any, TypeId},
     cell::RefCell,
-    collections::HashMap,
     fmt,
     future::Future,
     pin::Pin,
@@ -22,7 +20,6 @@ pub(crate) static COUNT: AtomicUsize = AtomicUsize::new(0);
 
 thread_local!(
     static HANDLE: RefCell<Option<ArbiterHandle>> = RefCell::new(None);
-    static STORAGE: RefCell<HashMap<TypeId, Box<dyn Any>>> = RefCell::new(HashMap::new());
 );
 
 pub(crate) enum ArbiterCommand {
@@ -121,7 +118,6 @@ impl Arbiter {
 
                     System::set_current(sys);
 
-                    STORAGE.with(|cell| cell.borrow_mut().clear());
                     HANDLE.with(|cell| *cell.borrow_mut() = Some(hnd.clone()));
 
                     // register arbiter
@@ -156,7 +152,6 @@ impl Arbiter {
         let hnd = ArbiterHandle::new(tx);
 
         HANDLE.with(|cell| *cell.borrow_mut() = Some(hnd.clone()));
-        STORAGE.with(|cell| cell.borrow_mut().clear());
 
         local.spawn_local(ArbiterRunner { rx });
 
@@ -214,54 +209,6 @@ impl Arbiter {
     pub fn join(self) -> thread::Result<()> {
         self.thread_handle.join()
     }
-
-    /// Insert item into Arbiter's thread-local storage.
-    ///
-    /// Overwrites any item of the same type previously inserted.
-    pub fn set_item<T: 'static>(item: T) {
-        STORAGE.with(move |cell| cell.borrow_mut().insert(TypeId::of::<T>(), Box::new(item)));
-    }
-
-    /// Check if Arbiter's thread-local storage contains an item type.
-    pub fn contains_item<T: 'static>() -> bool {
-        STORAGE.with(move |cell| cell.borrow().contains_key(&TypeId::of::<T>()))
-    }
-
-    /// Call a function with a shared reference to an item in this Arbiter's thread-local storage.
-    ///
-    /// # Panics
-    /// Panics if item is not in Arbiter's thread-local item storage.
-    pub fn get_item<T: 'static, F, R>(mut f: F) -> R
-    where
-        F: FnMut(&T) -> R,
-    {
-        STORAGE.with(move |cell| {
-            let st = cell.borrow();
-
-            let type_id = TypeId::of::<T>();
-            let item = st.get(&type_id).and_then(downcast_ref).unwrap();
-
-            f(item)
-        })
-    }
-
-    /// Call a function with a mutable reference to an item in this Arbiter's thread-local storage.
-    ///
-    /// # Panics
-    /// Panics if item is not in Arbiter's thread-local item storage.
-    pub fn get_mut_item<T: 'static, F, R>(mut f: F) -> R
-    where
-        F: FnMut(&mut T) -> R,
-    {
-        STORAGE.with(move |cell| {
-            let mut st = cell.borrow_mut();
-
-            let type_id = TypeId::of::<T>();
-            let item = st.get_mut(&type_id).and_then(downcast_mut).unwrap();
-
-            f(item)
-        })
-    }
 }
 
 /// A persistent future that processes [Arbiter] commands.
@@ -292,11 +239,3 @@ impl Future for ArbiterRunner {
         }
     }
 }
-
-fn downcast_ref<T: 'static>(boxed: &Box<dyn Any>) -> Option<&T> {
-    boxed.downcast_ref()
-}
-
-fn downcast_mut<T: 'static>(boxed: &mut Box<dyn Any>) -> Option<&mut T> {
-    boxed.downcast_mut()
-}
diff --git a/actix-rt/tests/tests.rs b/actix-rt/tests/tests.rs
index b2607a91..f54e9909 100644
--- a/actix-rt/tests/tests.rs
+++ b/actix-rt/tests/tests.rs
@@ -140,35 +140,6 @@ fn arbiter_drop_no_panic_fut() {
     arbiter.join().unwrap();
 }
 
-#[test]
-fn arbiter_item_storage() {
-    let _ = System::new();
-
-    let arbiter = Arbiter::new();
-
-    assert!(!Arbiter::contains_item::<u32>());
-    Arbiter::set_item(42u32);
-    assert!(Arbiter::contains_item::<u32>());
-
-    Arbiter::get_item(|&item: &u32| assert_eq!(item, 42));
-    Arbiter::get_mut_item(|&mut item: &mut u32| assert_eq!(item, 42));
-
-    let thread = thread::spawn(move || {
-        Arbiter::get_item(|&_item: &u32| unreachable!("u32 not in this thread"));
-    })
-    .join();
-    assert!(thread.is_err());
-
-    let thread = thread::spawn(move || {
-        Arbiter::get_mut_item(|&mut _item: &mut i8| unreachable!("i8 not in this thread"));
-    })
-    .join();
-    assert!(thread.is_err());
-
-    arbiter.stop();
-    arbiter.join().unwrap();
-}
-
 #[test]
 #[should_panic]
 fn no_system_current_panic() {