KEY IDEA Use a diversified test strategy that will serve the mission.

Test Strategy “How we plan to cover the product so as to develop an adequate assessment of quality.” A good test strategy is: Product-Specific Risk-focused Diversified Practical

Test Strategy Test Approach and Test Architecture are other terms commonly used to describe what I’m calling test strategy. Example of a poorly stated (and probably poorly conceived) test strategy: “We will use black box testing, cause-effect graphing, boundary testing, and white box testing to test this product against its specification.”

Test Strategy Makes use of test techniques. May be expressed by test procedures and cases. Not to be confused with test logistics, which involve the details of bringing resources to bear on the test strategy at the right time and place. You don’t have to know the entire strategy in advance. The strategy should change as you learn more about the product and its problems.

Test Cases/Procedures Test cases and procedures should manifest the test strategy. If your strategy is to “execute the test suite I got from Joe Third-Party”, how does that answer the prime strategic questions: How will you cover the product and assess quality? How is that practical and justified with respect to the specifics of this project and product? If you don’t know, then your real strategy is that you’re trusting things to work out.

Produce a test strategy for DecideRight Exercise Produce a test strategy for DecideRight

Test Strategy Heuristic: Diverse Half-Measures There is no single technique that finds all bugs. We can’t do any technique perfectly. We can’t do all conceivable techniques. Use “diverse half-measures”-- lots of different points of view, approaches, techniques, even if no one strategy is performed completely.

Strategy Heuristic: Function/Data Square Functions smoke testing Function testing Data reliability testing risk testing

The Fallacy of Repeated Tests: Clearing Mines

Totally Repeatable Tests Won’t Clear the Minefield mines fixes

Variable Tests are Therefore More Effective mines fixes

Exercise Find at least two situations where the heuristic: “Variable tests are better than repeated tests” is WRONG.