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Friday, March 19, 2010

How does a conventional tester fit into an agile environment?

When I think 'agile' I think test driven development (TDD). In TDD, the programmers actually write the tests first then write code to make the tests pass. If you look at something like Eclipse IDE, I can write a jUnit class that creates the code to instantiates a class that does not exist yet. Eclipse will complain about the non-existent class and offer to create the class for me (without the body). If I write calls to methods which do not exist, Eclipse will complain about the non-existent methods and offer to write the method for me (without the body).

In Agile development you have sprints. A sprint is typically a week. On most agile projects I have worked on, the QA staff are involved from the very beginning of each sprint. Every Monday (or some other day) all the stakeholders (developers, business analysts, testers, etc.) get together to decide what will be completed in the next sprint. They will come up with "user stories" (sort of like requirements). Everyone signs off on the sprint (meaning the stories should cover all the requirements and from that all the test scenarios plus test cases).

As each feature is written, there is daily deployment (or more often). As QA Tester I would write automation to conduct Integration and System level tests.

The most important aspect of agile development is fast turn around. On a traditional SDLC, I would often not see a functioning application until weeks after a developer has created it. By the time I am testing the first feature the developer could be done with that feature and working on something totally different. If I file a defect report on a feature a developer completed 3 weeks ago, she has to stop what she is working on, recall the code for the feature I am testing, fix the bug then get back to the new feature she was originally working on. This can be quite disruptive.

With agile development, a developer makes a change, compiles the code, runs the unit tests. If something she did breaks a unit test she knows in seconds. If it passes the unit test she can check the change in. The QA Tester can then build and test the application.

With the frameworks I worked on, the application would get built automatically by a nightly build process. All unit tests would get run on it. There might also be static analysis tools run on the project before compiling. Once the project is built and unit tests pass it would get deployed to test machines and the QA automation suite would be run. This all happens after business hours. In the morning, I would examine the test results. Sometimes a change in the program breaks my automation so I would do some maintenance on the automation and re-run the tests which failed. If there was an actual failure in the application and my automation found it, I would file a defect report.

On a daily basis the team would meet to talk about what was done the previous 24 hours and what would be the goal for each person in the next 24 hours (this is scrum, a form of agile development). I would bring up any defects I found at the scrum.

Fast turn around and immediate feedback is key to a good agile development. I would write regression tests to make sure defects found and fixed do not creep back into the product but I would also work with the developers to bring the regression tests into the unit test framework. This way the defect can be caught sooner should it creep back in.

Because the number of regression test grow with each iteration (sprint), it is recommended that they be automated. This frees the test team to conduct manual test efforts towards new features.

The most important thing to understand as a tester in an agile development environment is that there is a STRONG belief in minimal documentation. Source code should be self-documenting. The reason for this, and I have seen this on EVER traditional development team, is because the documentation is often neglected. No documentation is often better than wrong documentation. If there is no documentation and the developer has not gotten to the point were their code is self-documenting, they will be forced to look at the code and figure out what it does, rather than read outdated documentation and believe it does something different than it really does.

To understand the requirements of the software, you look at the unit tests. These should also be self-documenting and there should be one unit test for each requirement (user story).

As a tester, I will not expect to get a set of requirements. If I need to, I will take notes at the planning meeting (beginning of each sprint) and update them at each daily meeting (scrum).

The key to success for the tester will be communication. Without communication between the tester, the developer, business analysts and project stakeholders, it will be extremely difficult for the tester to properly test the application.

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