--- title: "A sneak Preview of Typemock Racer : Thread Deadlock Finder" url: "https://osherove.com/blog/2008/7/8/a-sneak-preview-of-typemock-racer-thread-deadlock-finder.md" canonical: "https://osherove.com/blog/2008/7/8/a-sneak-preview-of-typemock-racer-thread-deadlock-finder.html" published: "2008-07-08T08:42:28" updated: "2008-07-08T08:42:28" tags: ["Agile", "Agile Related", "Art Of Unit Testing", "Cool Tools", "General Software Devel...", "Unit Testing"] author: "Roy Osherove" description: "Here's a sneak preview of the upcoming Typemock Racer product, which I'm currently working on. We should be out in private CTP in a couple of weeks I hope. Typemock Racer tries to solve one huge problem for developers…" usage: "Licensed under CC BY 4.0 — reuse, quote and adapt with attribution (Roy Osherove, link to the original page)." license: "https://creativecommons.org/licenses/by/4.0/" --- # A sneak Preview of Typemock Racer : Thread Deadlock Finder By Roy Osherove July 8, 2008 In [Agile](https://osherove.com/blog/category/agile), [Agile Related](https://osherove.com/blog/category/agile-related), [Art Of Unit Testing](https://osherove.com/blog/category/art-of-unit-testing), [Cool Tools](https://osherove.com/blog/category/cool-tools), [General Software Devel...](https://osherove.com/blog/category/general-software-devel), [Unit Testing](https://osherove.com/blog/category/unit-testing) **Historical article** · Originally published July 8, 2008; technical details may be outdated. Here's a sneak preview of the upcoming [Typemock](http://www.typemock.com/) Racer product, which I'm currently working on. We should be out in private CTP in a couple of weeks I hope. Typemock Racer tries to solve one huge problem for developers working in multi threaded environments: Detecting code that can result in deadlocks or race conditions. It does this by providing a framework API which you can use in your tests (under NUnit for example), that allows you to execrise your code under test until it finds a deadlock or times out. Here's an example of how you'd use it. Consider the following class which has two methods, that if run by two seperate threads, can result in a deadlock condition: At some point in time the threads could execute such that thread 1 is waiting on resource b, which is held by thread two , which is waiting on resource a, held by thread 1 - a pure deadlock. Given this class we can write a test that looks like this: The ThreadTest class has an "AddThreadAction" method that receives a delegate. you can use it to invoke your own code, it will be invoked in a different thread. IN this example we are creating two threads, each one running a different method on MyClassWithLocks. We can just right click and run the test with TestDriven.NET to recieve the following results: The output states that there is a deadlock that was found, with the exact steps that happened (with line locations) to reproduce this. It currently only works with lock (monitor.Enter\\Exit) but will support all locking constructs in .NET. What if the methods you point to create their own threads? Like this: Here is the output that you'd get if you run this test: ## More in Agile [All posts in Agile](https://osherove.com/blog/category/agile) - Jul 12, 2008 ### [Over Specification in Tests](https://osherove.com/blog/2008/7/12/over-specification-in-tests.html) - Jul 10, 2008 ### [Poll: What threading features do you use?](https://osherove.com/blog/2008/7/10/poll-what-threading-features-do-you-use.html) - Jul 6, 2008 ### [Is Moq too poweful?](https://osherove.com/blog/2008/7/6/is-moq-too-poweful.html) - Jul 5, 2008 ### [Extending Depender with your own custom dependency rules](https://osherove.com/blog/2008/7/5/extending-depender-with-your-own-custom-dependency-rules.html) --- ## About the author **Roy Osherove**: Senior Solutions Architect at AWS working on AI for production and AI-driven development; author of The Art of Unit Testing and Elastic Leadership, with about 20 years of consulting and training on unit testing, TDD, team leadership and continuous delivery. ### Sites - [RobotPaper](https://robotpaper.ai/): This blog: AI patterns and anti-patterns, AI and coding agents, and engineering leadership. - [osherove.com](https://osherove.com): Roy's personal site. Author of The Art of Unit Testing and Elastic Leadership; consulting and training on unit testing, TDD, team leadership and continuous delivery, plus about 20 years of blog posts. - [The Art of Unit Testing](https://www.artofunittesting.com): The Art of Unit Testing, 3rd Edition (Manning): readable, maintainable, trustworthy unit tests, plus TDD workshops in C#, JavaScript, Java and Kotlin. - [5whys.com](https://www.5whys.com): Roy's writing on software team leadership: self-organizing teams, surviving chaos, learning mode and the Elastic Leadership model. - [Pipeline Driven](https://pipelinedriven.org): Continuous delivery and DevOps practices: build patterns, pipeline-friendly testing, DevOps metrics and enterprise DevOps. - [Elastic Leadership](https://www.elasticleadership.com): Elastic Leadership, Roy's framework for software team leaders (survival, learning and self-organizing modes). ### Social - X: https://x.com/royosherove - LinkedIn: https://www.linkedin.com/in/osherove/ ### Contact - Contact form: https://forms.gle/jQSx5KoXvrVA1JCK7 ### License Licensed under CC BY 4.0 — reuse, quote and adapt with attribution (Roy Osherove, link to the original page). License: https://creativecommons.org/licenses/by/4.0/