When
As per the Test Process (STLC), test cases are developed during the Test Design activity. Once all the requirements have been gathered, analysed and the test cases have been developed. This is exactly the time to decide on which test cases to be automated.
How
Not all test cases will be automated. The following criteria will be used in determining which test cases to be automated:
- Features/Functionalities or flows that are critical to business.
- Tests that need to be run repeatedly e.g. smoke, sanity and regression tests.
- Tests that need to run against multiple configurations — different OS & Browser combinations.
- Tests that execute the same workflow but use different data for its inputs for each test run e.g. data-driven.
- Tests that involve entering large volumes of data i.e. very tedious
- Tests that can be used for performance testing.
- Tests that take a long time to perform i.e. complex test cases that may take overnight or days.