A workaround for testing against CloudTable. Although CloudTable has a lot of virtual methods that can be easily mocked some examples don't work with dynamic mocking such as CreateQuery<T> with System.Linq, but there is a way!

Azure_Function_Test_With_Table_Binding.cs

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.Cosmos.Table;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Primitives;
using RichardSzalay.MockHttp;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using Xunit;

namespace AzureFunctionTesting
{
    public class Azure_Function_Test_With_Table_Binding
    {
        [Fact]
        public void Should_be_able_to_stub_out_a_CloudTable()
        {
            var storageAccount = StorageAccount.NewFromConnectionString("UseDevelopmentStorage=true");
            var client = storageAccount.CreateCloudTableClient();

            var mockedRequest = new MockHttpMessageHandler()
                .When("http://127.0.0.1:10002/devstoreaccount1/pizzas*")
                .Respond("application/json", 
                @"{
                    ""value"": [
                        {
                            ""Name"": ""Pepperoni"",
                            ""Price"": 9.99
                        }
                    ]
                }");

            client.TableClientConfiguration.RestExecutorConfiguration.DelegatingHandler = new MockRequestAdapter(mockedRequest);
            var table = client.GetTableReference("pizzas");

            var request = new DefaultHttpContext().Request;
            request.Query = new QueryCollection(new Dictionary<string, StringValues> { { "Pizza", new StringValues("Pepperoni") } });

            var result = PizzaStore.Run(request, table, null);

            Assert.IsType<OkObjectResult>(result);
        }
    }

    public class MockRequestAdapter : DelegatingHandler
    {
        private readonly MockedRequest _mockedRequest;

        public MockRequestAdapter(MockedRequest mockedRequest) : base()
        {
            _mockedRequest = mockedRequest;
        }

        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            return await _mockedRequest.SendAsync(new HttpRequestMessage(request.Method, request.RequestUri), cancellationToken);
        }
    }

    public static class PizzaStore
    {
        [FunctionName("PizzaStore")]
        public static IActionResult Run(
            [HttpTrigger(AuthorizationLevel.Function, "get", Route = null)] HttpRequest req,
            [Table("pizzas", Connection = "AzureWebJobsStorage")] CloudTable cloud,
            ILogger log)
        {
            if (req.Query.TryGetValue("Pizza", out var value))
            {
                var pizza = cloud.CreateQuery<Pizza>().Where(p => p.Name == value.ToString()).SingleOrDefault();

                return new OkObjectResult(new { Pizza = pizza.Name, Price = pizza.Price });
            }

            return new NotFoundResult();
        }
    }

    public class Pizza : TableEntity
    {
        public string Name { get; set; }
        public double Price { get; set; }
    }
}