A technique used in software quality assurance, this method focuses on the valid transformations a system can undergo. It involves modeling the various operational modes of a system and the permissible shifts between them. For example, consider a simple online shopping cart. It may exist in an ‘Empty’ state initially. Adding an item transitions it to a ‘Populated’ state. Clicking ‘Checkout’ could lead to a ‘Payment Processing’ state, and finally, a ‘Order Confirmed’ state. Each of these changes, triggered by specific inputs or events, forms the basis of this testing approach.
This methodology offers significant advantages in identifying flaws in system behavior and design. By mapping out all possible operational modes and the permitted transitions between them, testers can ensure that the application responds correctly to all expected inputs and handles unexpected ones gracefully. Historically, this approach has been particularly valuable in testing embedded systems, communication protocols, and applications where the order of operations is critical for correct functionality. The clarity and structure it provides helps to uncover errors that might be missed by other testing approaches.
