1 files changed, 23 insertions, 5 deletions
diff --git a/spec/ruby/core/kernel/sleep_spec.rb b/spec/ruby/core/kernel/sleep_spec.rb
index 32da6344c1..0570629723 100644
--- a/spec/ruby/core/kernel/sleep_spec.rb
+++ b/spec/ruby/core/kernel/sleep_spec.rb
@@ -1,5 +1,4 @@
 require_relative '../../spec_helper'
-require_relative 'fixtures/classes'
 
 describe "Kernel#sleep" do
   it "is a private method" do
@@ -33,10 +32,6 @@ describe "Kernel#sleep" do
     -> { sleep(-1) }.should raise_error(ArgumentError)
   end
 
-  it "raises a TypeError when passed nil" do
-    -> { sleep(nil)   }.should raise_error(TypeError)
-  end
-
   it "raises a TypeError when passed a String" do
     -> { sleep('2')   }.should raise_error(TypeError)
   end
@@ -55,6 +50,29 @@ describe "Kernel#sleep" do
     t.wakeup
     t.value.should == 5
   end
+
+  ruby_version_is ""..."3.3" do
+    it "raises a TypeError when passed nil" do
+      -> { sleep(nil)   }.should raise_error(TypeError)
+    end
+  end
+
+  ruby_version_is "3.3" do
+    it "accepts a nil duration" do
+      running = false
+      t = Thread.new do
+        running = true
+        sleep(nil)
+        5
+      end
+
+      Thread.pass until running
+      Thread.pass while t.status and t.status != "sleep"
+
+      t.wakeup
+      t.value.should == 5
+    end
+  end
 end
 
 describe "Kernel.sleep" do