I figured this title was appropriate considering it’s been a month since our last episode. We’ve all been incredibly busy so we hope you’ve been patient waiting and maybe, just maybe it was worth the wait! We’ve crammed quite a bit into this episode which is all about testing. Follow the more link to see the show notes for this particular episode and don’t forget to click one of the share buttons there to let all your friends know about the podcast!In this episode we’re primarily talking about Unit Testing. While that’s the focus of the podcast, we also touch on other types of testing so you’ll get a basic understanding of the fundamental differences between the types of tests. Just keep in mind – the testing we’re talking about is writing code to test your code. It’s not someone going through and clicking on items in your UI to make sure they work. We’re talking about code testing code to preemptively find problems before they become big problems.
It’s the holiday season and we would be remiss if we didn’t mention our favorite games right now.
Vistor Pattern Re-Visited
@TrentApple and loldot both shared the ExpressionVisitor.
Click here to see an example of the ExpressionVisitor class
Mail from You
Ray wanted to try an anti-SQL database. Ended up with db4o. Unfortunately it looks like it may be dead.
Here’s the link to db4o…
Maybe do a podcast on object to database storage. Database mappers of various sorts.
Lewis wants us to create a list of our recommended tools. Check back here in the future and we’ll have a link to the post we create that lists out our favorite developer tools. Everything from command line replacement tools, comparison tools, text editors, etc.
Favorite tools of 2014 Coming Soon!
Marcus wants to hear a podcast on Reactive Extensions. We may be getting an expert on the show to speak about this stuff….
Testing in general
- Testing as you go (you running through your app to make sure it works)
- Automated testing (run from command line, build server, etc.)
Several types of testing (not an exhaustive list):
- Unit testing – testing small pieces of code that have as few dependencies as possible
- Usually fast running, smaller tests
- Functional testing – testing how portions of an application work when hooked into its dependencies (databases, web services, etc)
- UI testing
- Selenium testing for web applications – fragile? difficult to maintain?
- Record & Replay / Macro type testing
- Take longer to run as it’s stepping through an app like a user would
- Regression testing – tests that ensure newer features haven’t broken older features that should still function the way they did previously
- Load testing – making sure a system can continue to function when put under high load
- Performance testing – making sure your application performs up to some predetermined standard
- Security testing – ensuring your application is as secure as possible given
For a single method that you want to test, you may create a dozen test methods to ensure that when you call that one method you always get your expected results. So, speaking of unit tests, you’re typically not writing ONE unit test to test an existing (or new) method, rather you’re creating a number of small unit tests to be concise.
The Triple A Pattern:
- Arrange – set up your variables
- Act – call the method under test
- Assert – did the method do what you expected it to do?
Why not just write functional tests as they test higher up?
Should the Singleton get blasted some more?! Michael tries to defend his true love…
Unit tests should be able to run out of order – this “proves” that you don’t have any bad dependencies lying around.
Testing Pyramid – Michael Cohn
- GUI Tests
- Acceptance / Functional Tests
- Unit Tests
Test Driven Development – TDD
Should you test first?
- Fewer errors
- Catch errors sooner
- Living documentation?
- Automatic regression harness
- Forces looser coupling of code
- SHORTER FEEDBACK LOOP – you’ll find out if there’s a problem quickly
- You can AUTOMATE IT! – run on your box, on a build server, etc.
- Jasmine – behavior driven development framework
- Karma – testing task runner
These find your tests and runs them and tells you what succeeds and what fails, typically looking at classes that have been attributed as test classes.
.NET teseting frameworks:
- NUnit – One of the most popular for .NET
- MSTest – Bundled with versions of Visual Studio but has some shortcomings -no parameterized tests?!?!
Java’s primary testing framework is JUnit
Why Does Testing Suck?
- It’s hard!
- I already know it works!
- Class / Interface / Code explosion
- Dependencies – Injection / Mocking
- What’s your coverage?
Resources – Links to Other Things We Mention in the Show
Huge list of testing resources:
Code Complete – excellent guide on complete programming
Art of Unit Testing – Learn to unit test from the ground up