1 files changed, 47 insertions, 0 deletions
diff --git a/test/scheduler/test_mutex.rb b/test/scheduler/test_mutex.rb
new file mode 100644
index 0000000000..8395e5522f
--- /dev/null
+++ b/test/scheduler/test_mutex.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+require 'test/unit'
+require_relative 'scheduler'
+
+class TestSchedulerMutex < Test::Unit::TestCase
+  def test_mutex_synchronize
+    mutex = Mutex.new
+
+    thread = Thread.new do
+      scheduler = Scheduler.new
+      Thread.current.scheduler = scheduler
+
+      Fiber do
+        assert_equal Thread.scheduler, scheduler
+
+        mutex.synchronize do
+          assert_nil Thread.scheduler
+        end
+      end
+    end
+
+    thread.join
+  end
+
+  def test_mutex_deadlock
+    mutex = Mutex.new
+
+    thread = Thread.new do
+      scheduler = Scheduler.new
+      Thread.current.scheduler = scheduler
+
+      Fiber do
+        assert_equal Thread.scheduler, scheduler
+
+        mutex.synchronize do
+          Fiber.yield
+        end
+      end
+      
+      assert_raise ThreadError do
+        mutex.lock
+      end
+    end
+
+    thread.join
+  end
+end