1 files changed, 38 insertions, 0 deletions
diff --git a/spec/rubyspec/core/mutex/unlock_spec.rb b/spec/rubyspec/core/mutex/unlock_spec.rb
new file mode 100644
index 0000000000..4601fde634
--- /dev/null
+++ b/spec/rubyspec/core/mutex/unlock_spec.rb
@@ -0,0 +1,38 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "Mutex#unlock" do
+  it "raises ThreadError unless Mutex is locked" do
+    mutex = Mutex.new
+    lambda { mutex.unlock }.should raise_error(ThreadError)
+  end
+
+  it "raises ThreadError unless thread owns Mutex" do
+    mutex = Mutex.new
+    wait = Mutex.new
+    wait.lock
+    th = Thread.new do
+      mutex.lock
+      wait.lock
+    end
+
+    # avoid race on mutex.lock
+    Thread.pass until mutex.locked?
+    Thread.pass while th.status and th.status != "sleep"
+
+    lambda { mutex.unlock }.should raise_error(ThreadError)
+
+    wait.unlock
+    th.join
+  end
+
+  it "raises ThreadError if previously locking thread is gone" do
+    mutex = Mutex.new
+    th = Thread.new do
+      mutex.lock
+    end
+
+    th.join
+
+    lambda { mutex.unlock }.should raise_error(ThreadError)
+  end
+end