If you have incomplete requirements then you have to do Exploratory Testing where you need to communicate with business analyst seniors developers team mates for better understanding of the functionality and also while research on the AUT so that you can understanding the flow and functionality.
If the requirements are incomplete / Unclear it is the tester's responsibility to get the details from various sources like BA Designers Developers etc. You cannot proceed further unless you are clear with requirements.
If the requirements are unclear then I can follow the below steps.
1. First of all I will prepare the review report with all clarifications/doubts about the unclear requirements. 2. Next sent to the concerned persons like BA if available and get the required information. 3. If you (tester) have a direct contact with client then ask him directly via emails or phone in my project we are using a common tool we can post all our doubts there and concerned persons will respond to them.
The first thing needs to be done is the Requirement analysis. The testing process should be started if and only if the requirement is freezed. Infact the estimation of testing will vary depends on the requirement updations and clarifications.
If requirements are unavailable or incomplete it makes a difficult task to go about with test case design. In such a case the following can help:
1) Arrange a session on project requirements with BA/SA to fill in the incomplete gaps.
2) Understand the requirements from them. Draw use cases or high level scenarios and get it reviewed from BA to check that you are on a right track.
3) From these uses cases/ high level scenarios come up with test cases and again get it reviewed so that you rework on the same and your final set of test cases are ready.
4) If possible even prioritize the test cases in order of each requirement's criticality which will help in effective test execution.
If the Requirement is in completed then we can do Exploratory Testing. While executing the Test what ever queries arised should be notable and send to the concern for answer. That should be clear and understandable.
