Add Mysql2NestedDeadlockTest, PostgresqlTransactionNestedTest

activerecord/test/cases/adapters/mysql2/nested_deadlock_test.rb

@@ -0,0 +1,76 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/connection_helper"
+
+module ActiveRecord
+  class Mysql2NestedDeadlockTest < ActiveRecord::Mysql2TestCase
+    self.use_transactional_tests = false
+
+    class Sample < ActiveRecord::Base
+      self.table_name = "samples"
+    end
+
+    setup do
+      @abort, Thread.abort_on_exception = Thread.abort_on_exception, false
+
+      @connection = ActiveRecord::Base.connection
+      @connection.clear_cache!
+
+      @connection.drop_table "samples", if_exists: true
+      @connection.create_table("samples") do |t|
+        t.integer "value"
+      end
+
+      Sample.reset_column_information
+    end
+
+    teardown do
+      ActiveRecord::Base.clear_active_connections!
+      @connection.drop_table "samples", if_exists: true
+
+      Thread.abort_on_exception = @abort
+    end
+
+    test "deadlock correctly raises Deadlocked inside nested SavepointTransaction" do
+      assert_raises(ActiveRecord::Deadlocked) do
+        barrier = Concurrent::CyclicBarrier.new(2)
+
+        s1 = Sample.create value: 1
+        s2 = Sample.create value: 2
+
+        begin
+          thread = Thread.new do
+            Sample.transaction(requires_new: false) do
+              Sample.transaction(requires_new: true) do
+                s1.lock!
+                barrier.wait
+                s2.update_attributes value: 1
+              end
+            end
+          end
+
+          begin
+            Sample.transaction(requires_new: false) do
+              Sample.transaction(requires_new: true) do
+                s2.lock!
+                barrier.wait
+                s1.update_attributes value: 2
+              end
+            end
+          ensure
+            thread.join
+          end
+
+        rescue ActiveRecord::StatementInvalid => e
+          if /SAVEPOINT active_record_. does not exist: ROLLBACK TO SAVEPOINT/ =~ e.to_s
+            assert nil, "ROLLBACK TO SAVEPOINT query issued for savepoint that no longer exists due to deadlock: #{e}"
+          else
+            raise e
+          end
+        end
+      end
+    end
+
+  end
+end

activerecord/test/cases/adapters/postgresql/transaction_nested_test.rb

@@ -0,0 +1,115 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/connection_helper"
+require "concurrent/atomic/cyclic_barrier"
+
+module ActiveRecord
+  class PostgresqlTransactionNestedTest < ActiveRecord::PostgreSQLTestCase
+    self.use_transactional_tests = false
+
+    class Sample < ActiveRecord::Base
+      self.table_name = "samples"
+    end
+
+    setup do
+      @abort, Thread.abort_on_exception = Thread.abort_on_exception, false
+
+      @connection = ActiveRecord::Base.connection
+
+      @connection.drop_table "samples", if_exists: true
+      @connection.create_table("samples") do |t|
+        t.integer "value"
+      end
+
+      Sample.reset_column_information
+    end
+
+    teardown do
+      @connection.drop_table "samples", if_exists: true
+
+      Thread.abort_on_exception = @abort
+    end
+
+    test "unserializable transaction raises SerializationFailure inside nested SavepointTransaction" do
+      assert_raises(ActiveRecord::SerializationFailure) do
+        before = Concurrent::CyclicBarrier.new(2)
+        after = Concurrent::CyclicBarrier.new(2)
+
+        begin
+          thread = Thread.new do
+            with_warning_suppression do
+              Sample.transaction(isolation: :serializable, requires_new: false) do
+                Sample.transaction(requires_new: true) do
+                  before.wait
+                  Sample.create value: Sample.sum(:value)
+                  after.wait
+                end
+              end
+            end
+          end
+
+          begin
+            with_warning_suppression do
+              Sample.transaction(isolation: :serializable, requires_new: false) do
+                Sample.transaction(requires_new: true) do
+                  before.wait
+                  Sample.create value: Sample.sum(:value)
+                  after.wait
+                end
+              end
+            end
+          ensure
+            thread.join
+          end
+        end
+      end
+    end
+
+    test "deadlock raises Deadlocked inside nested SavepointTransaction" do
+      with_warning_suppression do
+        assert_raises(ActiveRecord::Deadlocked) do
+          barrier = Concurrent::CyclicBarrier.new(2)
+
+          s1 = Sample.create value: 1
+          s2 = Sample.create value: 2
+
+          begin
+            thread = Thread.new do
+              Sample.transaction(requires_new: false) do
+                Sample.transaction(requires_new: true) do
+                  s1.lock!
+                  barrier.wait
+                  s2.update_attributes value: 1
+                end
+              end
+            end
+
+            begin
+              Sample.transaction(requires_new: false) do
+                Sample.transaction(requires_new: true) do
+                  s2.lock!
+                  barrier.wait
+                  s1.update_attributes value: 2
+                end
+              end
+            ensure
+              thread.join
+            end
+          end
+        end
+      end
+    end
+
+    private
+
+      def with_warning_suppression
+        log_level = ActiveRecord::Base.connection.client_min_messages
+        ActiveRecord::Base.connection.client_min_messages = "error"
+        yield
+      ensure
+        ActiveRecord::Base.clear_active_connections!
+        ActiveRecord::Base.connection.client_min_messages = log_level
+      end
+  end
+end