1 files changed, 25 insertions, 0 deletions
diff --git a/spec/rubyspec/core/threadgroup/enclose_spec.rb b/spec/rubyspec/core/threadgroup/enclose_spec.rb
new file mode 100644
index 0000000000..5827ddb6aa
--- /dev/null
+++ b/spec/rubyspec/core/threadgroup/enclose_spec.rb
@@ -0,0 +1,25 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "ThreadGroup#enclose" do
+  before :each do
+    @chan1,@chan2 = Channel.new,Channel.new
+    @thread = Thread.new { @chan1 << :go; @chan2.receive }
+    @chan1.receive
+  end
+
+  after :each do
+    @chan2 << :done
+    @thread.join
+  end
+
+  it "raises a ThreadError if attempting to move a Thread from an enclosed ThreadGroup" do
+    thread_group = ThreadGroup.new
+    default_group = @thread.group
+    thread_group.add(@thread)
+    thread_group.enclose
+    lambda do
+      default_group.add(@thread)
+    end.should raise_error(ThreadError)
+  end
+end