shared_examples_for 'is a database with an upsert trick' do
  describe :row do
    it "works for a single row (base case)" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Jerry', :gender => 'male'}]) do
        upsert.row({:name => 'Jerry'}, {:gender => 'male'})
      end
    end
    it "works for a single row (not changing anything)" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Jerry', :gender => 'male'}]) do
        upsert.row({:name => 'Jerry'}, {:gender => 'male'})
        upsert.row({:name => 'Jerry'}, {:gender => 'male'})
      end
    end
    it "works for a single row (changing something)" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Jerry', :gender => 'neutered'}]) do
        upsert.row({:name => 'Jerry'}, {:gender => 'male'})
        upsert.row({:name => 'Jerry'}, {:gender => 'neutered'})
      end
      Pet.where(:gender => 'male').count.must_equal 0
    end

    it "works for a single row with implicit nulls" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Inky', :gender => nil}]) do
        upsert.row({:name => 'Inky'}, {})
        upsert.row({:name => 'Inky'}, {})
      end
    end
    it "works for a single row with explicit nulls" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Inky', :gender => nil}]) do
        upsert.row({:name => 'Inky'}, {:gender => nil})
        upsert.row({:name => 'Inky'}, {:gender => nil})
      end
    end
    # it "works for a single row upserted many times" do
    #   assert_creates(Pet, [{:name => 'Jerry', :gender => 'male'}]) do
    #     ts = (0..5).map do
    #       Thread.new do
    #         upsert = Upsert.new new_connection, :pets
    #         upsert.row({:name => 'Jerry'}, {:gender => 'male'})
    #       end
    #     end
    #     ts.each { |t| t.join }
    #   end
    # end
  end
  describe :multi do
    it "works for multiple rows (base case)" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Jerry', :gender => 'male'}]) do
        upsert.multi do |xxx|
          xxx.row({:name => 'Jerry'}, :gender => 'male')
        end
      end
    end
    it "works for multiple rows (not changing anything)" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Jerry', :gender => 'male'}]) do
        upsert.multi do |xxx|
          xxx.row({:name => 'Jerry'}, :gender => 'male')
          xxx.row({:name => 'Jerry'}, :gender => 'male')
        end
      end
    end
    it "works for multiple rows (changing something)" do
      upsert = Upsert.new connection, :pets
      assert_creates(Pet, [{:name => 'Jerry', :gender => 'neutered'}]) do
        upsert.multi do |xxx|
          xxx.row({:name => 'Jerry'}, :gender => 'male')
          xxx.row({:name => 'Jerry'}, :gender => 'neutered')
        end
      end
      Pet.where(:gender => 'male').count.must_equal 0
    end
    # it "works for multiple rows upserted many times" do
    #   assert_creates(Pet, [{:name => 'Jerry', :gender => 'male'}]) do
    #     ts = (0..5).map do
    #       Thread.new do
    #         upsert = Upsert.new new_connection, :pets
    #         upsert.multi do
    #           row({:name => 'Jerry'}, :gender => 'male')
    #           row({:name => 'Jerry'}, :gender => 'male')
    #         end
    #       end
    #     end
    #     ts.each { |t| t.join }
    #   end
    # end
  end
end