Centralization leads to mediocrity at best.
Today I went to a seminar, organized by HP to promote their offerings in the quality management area. What struck me most was the 'Center of Excellence' notion. Basically the idea is that (big) organizations should centralize their quality-related activities into one unit (boldly named Center of Excellence), in order to reduce costs. HP is willing to support you in this endeavor with software and consulting. They even came up with their own maturity model which ranks organizations on one of several levels - the lowest called for some reason 'Manual Testing' and the highest of course being 'Center of Excellence'.
Somehow I don’t buy into this. I realize that cost saving measures are in vogue now, but my experience shows that centralization leads to mediocrity at best, not excellence.
Record/Playback does not work, but we all know this, don't we?
If you have ever had anything to do with UI test automation, you should know about recording. It is an ability that most tools (commercial or open source) have - you start the recording session in the tool and then just happily click through the test scenario on the application you are testing. Meanwhile the tool sits silently and records your actions, getting ready to replay them automatically when you want to. The ability to record the UI interactions is a marketing highlight for most automation tools. There are even some tools, where recording is the only way you can create test scripts.
On the surface it can really look like the best way to automate - you will be testing manually anyway, so why don't just record your tests to replay them at a later stage? Unfortunately the view that test automation is something as simple as pressing the record button has spread widely, mostly fueled by the hype of the tool vendors.
If you do not have any hands-on experience with test automation, you might miss a very important fact about the whole thing - it is not only about creating the scripts. In fact the actual script creation rarely takes more than 20-30% of the time you invest in automation. Here is a rough outline of all the things you have to do:
- Prepare the test environment
With automation you want to have a very consistent environment, with known data and configuration, where you execute your tests. Sometimes this is not possible - maybe you have to test in a live system, or you don't control every part of the system landscape. In such cases you can succeed only if you create smart automated tests that can anticipate and cope with all the expected changes in the environment. I will write more about this topic in the future, but for now let's just say that recording is not smart at all.
- Create the test scripts
This is the actual thing that recording addresses. It might seem that it is a very efficient way of creating test scripts, however in reality it is not. You will make errors while recording (like misclicks or mistypings). Correcting those errors in recorded scripts is most often difficult or even impossible. Also if you limit yourself to just repeating recorded sequences, you will not benefit from all the good things that automation can offer compared with manual testing (like data-driven tests for example).
- Execute the scripts
Or maybe I should say try to execute the scripts. My experience shows that unless you are testing something that has a very simple UI, recording tools often fail to create working scripts out of the box, even if you have managed to ensure absolutely consistent environment for the test execution. Recording lacks the intelligence to understand what you are doing and what your actual intentions are in a complex UI.
- Analyze the results
In case you are executing recorded scripts, you will be hoping desperately that they pass successfully. In case something goes wrong (which will be most of the time), you will have extremely hard time trying to understand if it was a bug in the product, an issue with the test script or maybe a change in the application UI.
The time spent in analysis of test results is probably the greatest time-waster in test automation and you can optimize this only by having proper logging on a higher semantic level than UI interactions. Again this is something that I intend to write about.
- Update your scripts
Software changes and you will either have to adapt your tests or throw them away. With recording it is mostly about throwing away. It is true that most of the tools now provide some ways to cope with simple changes in the UI, but those are still very limited. For example if a caption of a button changes from 'New' to 'New...', in most cases you will be able to adjust your scripts. With the good tools you will have to add the '...' only in one place, no matter how many times you click the button in your test. However, imagine that this button is replaced by a context menu. Most tools will let you somehow change this in their recorded scripts, but you will have to do this change every single place where the button was clicked in your scenario. Most probably you will just want to re-record it from scratch.
If you plan to do any serious automation, do not base the choice of your tool on how well it handles record and playback. In my opinion writing tests using the scripting language (and doing it right) is the only way to make UI automation really work.
I find recording only useful when I am testing with a new UI technology or a new automation tool and I want to quickly find out how it recognizes a particular UI control. In such cases recording a few mouse clicks and then looking at the generated script can be useful.