close our connection when we are done

activerecord/test/cases/scoping/default_scoping_test.rb

@@ -56,7 +56,10 @@ def test_default_scope_with_conditions_hash
 
   def test_default_scoping_with_threads
     2.times do
-      Thread.new { assert DeveloperOrderedBySalary.all.to_sql.include?('salary DESC') }.join
+      Thread.new {
+        assert DeveloperOrderedBySalary.all.to_sql.include?('salary DESC')
+        DeveloperOrderedBySalary.connection.close
+      }.join
     end
   end
 
@@ -360,9 +363,11 @@ def test_default_scope_is_threadsafe
     threads << Thread.new do
       Thread.current[:long_default_scope] = true
       assert_equal 1, ThreadsafeDeveloper.all.to_a.count
+      ThreadsafeDeveloper.connection.close
     end
     threads << Thread.new do
       assert_equal 1, ThreadsafeDeveloper.all.to_a.count
+      ThreadsafeDeveloper.connection.close
     end
     threads.each(&:join)
   end

activerecord/test/cases/transactions_test.rb

@@ -526,22 +526,20 @@ class ConcurrentTransactionTest < TransactionTest
     # This will cause transactions to overlap and fail unless they are performed on
     # separate database connections.
     def test_transaction_per_thread
-      assert_nothing_raised do
-        threads = (1..3).map do
-          Thread.new do
-            Topic.transaction do
-              topic = Topic.find(1)
-              topic.approved = !topic.approved?
-              topic.save!
-              topic.approved = !topic.approved?
-              topic.save!
-            end
-            Topic.connection.close
+      threads = 3.times.map do
+        Thread.new do
+          Topic.transaction do
+            topic = Topic.find(1)
+            topic.approved = !topic.approved?
+            assert topic.save!
+            topic.approved = !topic.approved?
+            assert topic.save!
           end
+          Topic.connection.close
         end
-
-        threads.each { |t| t.join }
       end
+
+      threads.each { |t| t.join }
     end
 
     # Test for dirty reads among simultaneous transactions.