1 files changed, 57 insertions, 0 deletions
diff --git a/test/ruby/test_threadgroup.rb b/test/ruby/test_threadgroup.rb
new file mode 100644
index 0000000000..ec95bd6419
--- /dev/null
+++ b/test/ruby/test_threadgroup.rb
@@ -0,0 +1,57 @@
+# frozen_string_literal: false
+require 'test/unit'
+
+class TestThreadGroup < Test::Unit::TestCase
+  def test_thread_init
+    thgrp = ThreadGroup.new
+    th = Thread.new{
+      thgrp.add(Thread.current)
+      Thread.new{sleep 1}
+    }.value
+    assert_equal(thgrp, th.group)
+  ensure
+    th.join
+  end
+
+  def test_frozen_thgroup
+    thgrp = ThreadGroup.new
+
+    t = Thread.new{1}
+    Thread.new{
+      thgrp.add(Thread.current)
+      thgrp.freeze
+      assert_raise(ThreadError) do
+        Thread.new{1}.join
+      end
+      assert_raise(ThreadError) do
+        thgrp.add(t)
+      end
+      assert_raise(ThreadError) do
+        ThreadGroup.new.add Thread.current
+      end
+    }.join
+    t.join
+  end
+
+  def test_enclosed_thgroup
+    thgrp = ThreadGroup.new
+    assert_equal(false, thgrp.enclosed?)
+
+    t = Thread.new{1}
+    Thread.new{
+      thgrp.add(Thread.current)
+      thgrp.enclose
+      assert_equal(true, thgrp.enclosed?)
+      assert_nothing_raised do
+        Thread.new{1}.join
+      end
+      assert_raise(ThreadError) do
+        thgrp.add t
+      end
+      assert_raise(ThreadError) do
+        ThreadGroup.new.add Thread.current
+      end
+    }.join
+    t.join
+  end
+end