In SCRUM approach User Story is used as a requirement. The best way to write the user story is “As a ___, I want___ so that I can ___.”

Example: As a user, I want to login to the screen so that I can book the tickets.

The test for determining whether or not a story is well understood and ready for the team to begin working on it is the INVEST acronym:

• I – Independent
• N – Negotiable
• V – Valuable
• E – Estimable
• S – Small
• T – Testable

This is a very common scenario seen in the projects which are using Scrum Approach. The team should always be PREPARED for that. But try to have a good conversation with the Product owner to not include in the current sprint and deferred to the next sprint. Changes in requirements sometimes taken as a feedback from the customer so that the product can be improved. We should be ready to embrace this change.

As a tester, they should take the generic approach by writing the generic test CASES (Login screen, user credentials). TILL the requirements are stable, try to wait if you are PLANNING to automate the test cases.

As a developer same approach can be used where chances of changes are minimal. Try to code using design PATTERNS and oops concepts (Components or package independent of each other), so that change in one component make minimal changes in another.