The process was a HackerRank test they asked me to do before they would speak to me. I was fine with it because they said it would only be 2-4 hours.

The test asked you to build a cloning service in C#. Basically, a thing that could do a deep clone on any object. They also added some attributes that could be put on any property or field, and would control whether that got a deep clone, a shallow clone, or was ignored.

I actually thought the test was well-written, as cloning is not that hard, but the addition of these attributes prevented just copy-pasting someone else's solution.

So, I was able to solve the problem easily in the time allotted. HOWEVER - they provided hardcoded test cases that your solution needed to pass.

The problem is that the test cases were WRONG. In one of them, they clearly marked a field as IGNORE, and then the test case tried to verify that they were equal. Well, of course, they aren't equal; you specifically asked me to IGNORE that field when cloning.

The sad part is, if I had just ignored the attributes altogether, I would have passed all the test cases. It's like they added the attributes afterward and forgot to update their tests? I don't know.

I chose to submit my solution as-is, and explained that it didn't pass all the tests but that I thought their tests were wrong, and I hoped they would give me a chance to defend the solution.

In the end, they never even responded to me. I'll never know if the test cases were indeed wrong, or if I misunderstood something.

Either way, I learned that you should probably never do coding tests without speaking to somebody at the company first.

How to build a cloning service in C#