Seth Eliot's Blog

I previously talked about the dog-bone approach to testing, and how we testers love our shapes such as the Test Pyramid.  But I did not connect the pyramid to the dog-bone.  Now permit me to remedy that

Pyramid

This is the Test Pyramid introduced by Mike Cohn in 2009

In brief it says

Unit Testing is foundational because

• It is earliest in the development cycle
• It gives specific information on the source of the bug (down to the line number in code)
• It is easiest to automate

UI tests should be kept to a minimum because they

• Are brittle, expensive, and time consuming
• Often redundant with Unit Tests, hitting the same code paths repeatedly through multiple UI tests

And service level testing is necessary to fill the gap that unit testing cannot test, but that we do not want to test through the UI.

Dog-bone

Take the pyramid and turn it on its side, and you have a great start to testing in your development cycle.  But I maintain that if your goal for testing is to understand the quality of your system, then something is missing especially after you go to production.   You must leverage the rich data from real users and real usage in production to understand the quality of your system.

The techniques by which we use this production data are called Testing in Production, therefore we get the dog-bone approach to testing