test/rake: avoid leaking threads

* test/rake/test_rake_multi_task.rb (teardown): clean up thread
  pool to avoid leaking threads.

* test/rake/test_rake_task_with_arguments.rb (teardown): ditto.

* test/rake/test_rake_thread_pool.rb: ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46206 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/rake/test_rake_multi_task.rb

@@ -13,6 +13,12 @@ class TestRakeMultiTask < Rake::TestCase
     @mutex = Mutex.new
   end
 
+  def teardown
+    Rake.application.thread_pool.join
+
+    super
+  end
+
   def add_run(obj)
     @mutex.synchronize do
       @runs << obj

test/rake/test_rake_task_with_arguments.rb

@@ -12,6 +12,7 @@ class TestRakeTaskWithArguments < Rake::TestCase
 
   def teardown
     Rake::TaskManager.record_task_metadata = false
+    Rake.application.thread_pool.join
 
     super
   end

test/rake/test_rake_thread_pool.rb

@@ -33,6 +33,8 @@ class TestRakeTestThreadPool < Rake::TestCase
     refute_equal threads[0], threads[1]
     refute_equal Thread.current, threads[0]
     refute_equal Thread.current, threads[1]
+  ensure
+    pool.join
   end
 
   def test_pool_creates_the_correct_number_of_threads
@@ -95,6 +97,8 @@ class TestRakeTestThreadPool < Rake::TestCase
     assert_raises(CustomError) do
       pool.future(2, &deep_exception_block).value
     end
+  ensure
+    pool.join
   end
 
   def test_pool_prevents_deadlock