Positive, Negative testing and test execution

Ideal flow of test execution , some days before a friend of mine (a fresher is testing field) asked me about positive, negative testing and the flow of test execution and his understanding inspired me for this post. As per my understanding, positive testing is ‘Test to pass’ that is testing done to confirm that the system meets the specified requirements. In these types of tests we usually do not input invalid conditions and main concentration should be on finding out the defects/bugs by executing the system as per the normal functionality. Under this we concentrate on the written requirements and normal flows and validate the system against it. In other words we validate that the system is working as per the documented requirements.

Coming on to negative testing, it is ‘Test to break’. Now that we are done with the normal testing we try to break the system by trying negative scenarios on it such as invalid inputs, unusual load and other negative scenarios so as to know the behavior of the system with such conditions. Suppose that a website is expected to have load of 1000 hits at a time then in negative testing we may try to overload along with the abnormal communication conditions.

Coming on to the test execution part, I follow a thumb rule that as a tester my job is to first validate that the system is working as per the written requirements (TEST TO PASS) and then after this I should try the negative scenarios (TEST TO BREAK). Remember, our first job is to execute the documented test cases since this is what we have agreed to deliver to the client and these are the test for which client is expecting the test report. So the order of execution should be first the positive tests and then the negative tests that is after positive testing we can try our hands on some undocumented testing (Ad-hoc and exploratory testing)