Top 20 NuGet testing Packages

A tiny testing library for your Unity container.
A tiny testing library for your StructureMap container.
HTTP server mock is a really useful tool for testing, it will help you to mock HTTP requests. Please have a look at the documentation for details:
An image reporter to be used with ApprovalTests.Net
Allows you to create a lightweight owin server with basic endpoints
Utilities to simplify automated tests that involve asynchronous operations
You can be friends with UWP App. And You can do anything to it!
XUnit test executor implementation for the Alias framework.
A set of additions to extend Webdriver
Quickly stub out 3rd party servers to be used against your automated development test cycle. Designed to feel familiar to use, without having restrictions forced upon you.
A transport for NSB that runs in memory for integration testing NSB endpoints.
Custom patterns could be seen from UIAVerify tool (see TestStack's fork of it) and handy to use in WPF apps because pattern registration has some means to inject new pattern into existing AutomationPeer's structure. Also was tested to some extent with WinForms.
Tools to help test with Entity Framework 6
Beautiful object graph assertions in C#.
Contains an implementation of DbContext mock that uses in memory collections for the DbSets
Inter application test enabler library
Simple BDD style testing library.
A library to enable deployment of Sql Databases using the DAC framework.
Generate Group testing framework, for use in stochastic automated testing, see examples in the project for usage.
Test specifications for XUnit in a BDD like style