From dd2e95fb26b89ce060631af0fd372b5780a443dd Mon Sep 17 00:00:00 2001
From: Samuel Williams <samuel.williams@oriontransfer.co.nz>
Date: Thu, 1 Oct 2020 13:44:23 +1300
Subject: [PATCH] Remove `Thread.scheduler` from public interface.

It's implementation is equivalent to:

Thread.current.scheduler unless Thread.current.blocking?
---
 test/fiber/test_mutex.rb | 13 ++++++-------
 thread.c                 |  2 +-
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/test/fiber/test_mutex.rb b/test/fiber/test_mutex.rb
index 258f5358a6..c38d45b189 100644
--- a/test/fiber/test_mutex.rb
+++ b/test/fiber/test_mutex.rb
@@ -11,10 +11,10 @@ class TestFiberMutex < Test::Unit::TestCase
       Thread.current.scheduler = scheduler
 
       Fiber.schedule do
-        assert_equal Thread.scheduler, scheduler
+        refute Thread.current.blocking?
 
         mutex.synchronize do
-          assert Thread.scheduler
+          refute Thread.current.blocking?
         end
       end
     end
@@ -83,9 +83,9 @@ class TestFiberMutex < Test::Unit::TestCase
 
         f = Fiber.schedule do
           assert_raise_with_message(RuntimeError, "bye") do
-            assert_same scheduler, Thread.scheduler
             mutex.lock
           end
+
           ran = true
         end
 
@@ -196,8 +196,9 @@ class TestFiberMutex < Test::Unit::TestCase
   end
 
   def test_mutex_deadlock
-    err = /No live threads left. Deadlock\?/
-    assert_in_out_err %W[-I#{__dir__} -], <<-RUBY, ['in synchronize'], err, success: false
+    error_pattern = /No live threads left. Deadlock\?/
+
+    assert_in_out_err %W[-I#{__dir__} -], <<-RUBY, ['in synchronize'], error_pattern, success: false
     require 'scheduler'
     mutex = Mutex.new
 
@@ -206,8 +207,6 @@ class TestFiberMutex < Test::Unit::TestCase
       Thread.current.scheduler = scheduler
 
       Fiber.schedule do
-        raise unless Thread.scheduler == scheduler
-
         mutex.synchronize do
           puts 'in synchronize'
           Fiber.yield
diff --git a/thread.c b/thread.c
index 510d8a028b..3aca71dd6c 100644
--- a/thread.c
+++ b/thread.c
@@ -5519,7 +5519,7 @@ Init_Thread(void)
     rb_define_method(rb_cThread, "backtrace", rb_thread_backtrace_m, -1);
     rb_define_method(rb_cThread, "backtrace_locations", rb_thread_backtrace_locations_m, -1);
 
-    rb_define_singleton_method(rb_cThread, "scheduler", rb_thread_scheduler, 0);
+    // rb_define_singleton_method(rb_cThread, "scheduler", rb_thread_scheduler, 0);
     rb_define_method(rb_cThread, "scheduler", rb_thread_scheduler_get, 0);
     rb_define_method(rb_cThread, "scheduler=", rb_thread_scheduler_set, 1);