System.Net.Http.OwinHttpMessageHandlerTests.Environment_should_contain_content_length_header C# (CSharp) Method

        public async Task Environment_should_contain_content_length_header()
        {
            OwinContext owinContext = null;
            var handler = new OwinHttpMessageHandler(env =>
            {
                owinContext = new OwinContext(env);
                return Task.FromResult(0);
            });

            using (var client = new HttpClient(handler))
            {
                var stringContent = new StringContent("hello");
                await client.PostAsync("http://localhost/", stringContent);
            }

            owinContext.Request.Headers.ContainsKey("Content-Length").ShouldBeTrue();
        }
    }