1 files changed, 55 insertions, 0 deletions
diff --git a/activerecord/test/cases/adapters/mysql2/transaction_test.rb b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
new file mode 100644
index 0000000000..edd5353ee3
--- /dev/null
+++ b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
@@ -0,0 +1,55 @@
+require "cases/helper"
+require "support/connection_helper"
+
+module ActiveRecord
+  class Mysql2TransactionTest < ActiveRecord::Mysql2TestCase
+    self.use_transactional_tests = false
+
+    class Sample < ActiveRecord::Base
+      self.table_name = "samples"
+    end
+
+    setup do
+      @connection = ActiveRecord::Base.connection
+      @connection.clear_cache!
+
+      @connection.transaction do
+        @connection.drop_table "samples", if_exists: true
+        @connection.create_table("samples") do |t|
+          t.integer "value"
+        end
+      end
+
+      Sample.reset_column_information
+    end
+
+    teardown do
+      @connection.drop_table "samples", if_exists: true
+    end
+
+    test "raises Deadlocked when a deadlock is encountered" do
+      assert_raises(ActiveRecord::Deadlocked) do
+        s1 = Sample.create value: 1
+        s2 = Sample.create value: 2
+
+        thread = Thread.new do
+          Sample.transaction do
+            s1.lock!
+            sleep 1
+            s2.update_attributes value: 1
+          end
+        end
+
+        sleep 0.5
+
+        Sample.transaction do
+          s2.lock!
+          sleep 1
+          s1.update_attributes value: 2
+        end
+
+        thread.join
+      end
+    end
+  end
+end