1 files changed, 33 insertions, 0 deletions
diff --git a/test/ruby/test_thread.rb b/test/ruby/test_thread.rb
index 0d924eea57..b5db362df4 100644
--- a/test/ruby/test_thread.rb
+++ b/test/ruby/test_thread.rb
@@ -22,3 +22,36 @@ class TestThread < Test::Unit::TestCase
   end
 end
 
+class TestThreadGroup < Test::Unit::TestCase
+  def test_thread_init
+    thgrp = ThreadGroup.new
+    Thread.new{
+      thgrp.add(Thread.current)
+      assert_equal(thgrp, Thread.new{sleep 1}.group)
+    }.join
+  end
+
+  def test_frozen_thgroup
+    thgrp = ThreadGroup.new
+    Thread.new{
+      thgrp.add(Thread.current)
+      thgrp.freeze
+      assert_raise(ThreadError) do
+        Thread.new{1}.join
+      end
+    }.join
+  end
+
+  def test_enclosed_thgroup
+    thgrp = ThreadGroup.new
+    thgrp.enclose
+    Thread.new{
+      assert_raise(ThreadError) do
+        thgrp.add(Thread.current)
+      end
+      assert_nothing_raised do
+        Thread.new{1}.join
+      end
+    }.join
+  end
+end