void ApplicationServicesIsSet()
        {
            var services = new ServiceCollection();
            var options  = new SerilogExtensionsOptions(services);

            Assert.Same(services, options.ApplicationServices);
        }
        void SetupActionNullRaisesArgumentNullException()
        {
            var services = new ServiceCollection();
            var options  = new SerilogExtensionsOptions(services);

            var ex = Assert.Throws <ArgumentNullException>(() => options.AddMessagEnricher(null));

            Assert.Equal("setupAction", ex.ParamName);
            Assert.Contains("setupAction can not be null.", ex.Message);
        }