How to test a random feature in MS Excel/WORD/PPT

Question

Interviewers often ask questions about testing a random feature in Excel, Word, Notepad etc.. I am someone who will be interviewing for a SDET position and has a SDE background not specifically SDET background. I am extremely interested in testing though so applied for a SDET position. So how should one go about testing a random feature in a software, especially word/excel/notepad kind of software? Exploratory testing? What about a feature like File-> open dialog in word/Excel/ How to tackle such interview questions? What is an interviewer specifically looking for in an experienced candidate when he/she asks such questions?

Answer 1

A few things that I believe will be valued:

• Creativity: do things that, if a user did them, the programmers would call the user stupid.
• Corner cases. Invent as many as you can.
• Illegal/unsupported actions - Are they handeled gracefully?
• Failure situations when interacting with external systems (such as the file system). E.g., in the File Open dialog, what happens if the file you choose to open is deleted by another user, or is located on a network drive to which the connection is lost, between the time it is selected and the time the user clicks OK?
• Performance. What happens if you open a folder with thousands of files?
• Security. What happens if you try to open a directory to which you do not have access?
• Internationalization. What happens if files or folders contain non-English characters?
• Unusual ways of doing things (overlaps with "Creativity"): What happens in the above scenarios if, instead of navigating to a folder and selecting a file, the user enters the full path of the file in the text box and hit enter?

Answer 2

Start by describing the different types of tests:

1. There is a BVT test (Build Verification Test) runs after every check-in made by a developer. It should run fast, and cover basic functionality
2. Functionality test: Covers all the features to verify the product matches the spec
3. Performance test: Measure performance of specific scenarios against benchmark
4. Stress test: A test running long time, to test memory leaks and robustness over time
5. More: code coverage, automated test, manual test, unit test, regression test, security test, penetration test, etc.

Assuming the interviewer will ask you to focus on functionality test, the trick would be to identify the equivalency classes. For example, when asked to test a @sum formula of excel, the equivalency classes may be: Positive numbers, Negative numbers, zero, result is MAX_INT, result is more than MAX_INT, result is less than MIN_INT, strings in cell, other non numeric values in cells, etc.

Other type of tests would have different characteristics. For example, for security tests, you should model the attack surface, follow the data, and basically see if the system has any security weakness.

For performance, you need to agree first what are the scenarios you want to benchmark. There is no performance work, unless you define the benchmark, and preferably automate it.

etc.