5 files changed, 111 insertions, 0 deletions
diff --git a/spec/ruby/core/threadgroup/add_spec.rb b/spec/ruby/core/threadgroup/add_spec.rb
new file mode 100644
index 0000000000..2921c1ab22
--- /dev/null
+++ b/spec/ruby/core/threadgroup/add_spec.rb
@@ -0,0 +1,39 @@
+require_relative '../../spec_helper'
+
+describe "ThreadGroup#add" do
+  before :each do
+    @q1, @q2 = Queue.new, Queue.new
+    @thread = Thread.new { @q1 << :go; @q2.pop }
+    @q1.pop
+  end
+
+  after :each do
+    @q2 << :done
+    @thread.join
+  end
+
+  # This spec randomly kills mspec worker like: https://ci.appveyor.com/project/ruby/ruby/build/9806/job/37tx2atojy96227m
+  # TODO: Investigate the cause or at least print helpful logs, and remove this `platform_is_not` guard.
+  platform_is_not :mingw do
+    it "adds the given thread to a group and returns self" do
+      @thread.group.should_not == nil
+
+      tg = ThreadGroup.new
+      tg.add(@thread).should == tg
+      @thread.group.should == tg
+      tg.list.include?(@thread).should == true
+    end
+
+    it "removes itself from any other threadgroup" do
+      tg1 = ThreadGroup.new
+      tg2 = ThreadGroup.new
+
+      tg1.add(@thread)
+      @thread.group.should == tg1
+      tg2.add(@thread)
+      @thread.group.should == tg2
+      tg2.list.include?(@thread).should == true
+      tg1.list.include?(@thread).should == false
+    end
+  end
+end
diff --git a/spec/ruby/core/threadgroup/default_spec.rb b/spec/ruby/core/threadgroup/default_spec.rb
new file mode 100644
index 0000000000..d7d4726cc2
--- /dev/null
+++ b/spec/ruby/core/threadgroup/default_spec.rb
@@ -0,0 +1,11 @@
+require_relative '../../spec_helper'
+
+describe "ThreadGroup::Default" do
+  it "is a ThreadGroup instance" do
+    ThreadGroup::Default.should be_kind_of(ThreadGroup)
+  end
+
+  it "is the ThreadGroup of the main thread" do
+    ThreadGroup::Default.should == Thread.main.group
+  end
+end
diff --git a/spec/ruby/core/threadgroup/enclose_spec.rb b/spec/ruby/core/threadgroup/enclose_spec.rb
new file mode 100644
index 0000000000..dd9a7a362d
--- /dev/null
+++ b/spec/ruby/core/threadgroup/enclose_spec.rb
@@ -0,0 +1,24 @@
+require_relative '../../spec_helper'
+
+describe "ThreadGroup#enclose" do
+  before :each do
+    @q1, @q2 = Queue.new, Queue.new
+    @thread = Thread.new { @q1 << :go; @q2.pop }
+    @q1.pop
+  end
+
+  after :each do
+    @q2 << :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
+    -> do
+      default_group.add(@thread)
+    end.should raise_error(ThreadError)
+  end
+end
diff --git a/spec/ruby/core/threadgroup/enclosed_spec.rb b/spec/ruby/core/threadgroup/enclosed_spec.rb
new file mode 100644
index 0000000000..a734256a64
--- /dev/null
+++ b/spec/ruby/core/threadgroup/enclosed_spec.rb
@@ -0,0 +1,14 @@
+require_relative '../../spec_helper'
+
+describe "ThreadGroup#enclosed?" do
+  it "returns false when a ThreadGroup has not been enclosed (default state)" do
+    thread_group = ThreadGroup.new
+    thread_group.enclosed?.should be_false
+  end
+
+  it "returns true when a ThreadGroup is enclosed" do
+    thread_group = ThreadGroup.new
+    thread_group.enclose
+    thread_group.enclosed?.should be_true
+  end
+end
diff --git a/spec/ruby/core/threadgroup/list_spec.rb b/spec/ruby/core/threadgroup/list_spec.rb
new file mode 100644
index 0000000000..b2ac64324a
--- /dev/null
+++ b/spec/ruby/core/threadgroup/list_spec.rb
@@ -0,0 +1,23 @@
+require_relative '../../spec_helper'
+
+describe "ThreadGroup#list" do
+  it "returns the list of threads in the group" do
+    q = Queue.new
+    th1 = Thread.new { q << :go; sleep }
+    q.pop.should == :go
+    tg = ThreadGroup.new
+    tg.add(th1)
+    tg.list.should include(th1)
+
+    th2 = Thread.new { q << :go; sleep }
+    q.pop.should == :go
+
+    tg.add(th2)
+    (tg.list & [th1, th2]).should include(th1, th2)
+
+    Thread.pass while th1.status and th1.status != 'sleep'
+    Thread.pass while th2.status and th2.status != 'sleep'
+    th1.run; th1.join
+    th2.run; th2.join
+  end
+end