[nullserver]

I inherited an ancient project that had literally tens of thousands of test.

I reviewed hundreds of them, tried rewriting dozens of them. Eventually, realize that essentially all of the tests were just testing that mock data being manually manipulated by the test gave the result of test expected.

Absolutely nothing useful was actually being tested.

Some team spent a couple of years writing an unholy number of tests as a complete waste of time. Basically just checking off a box that code had tests.

[randomdata]

The first box on the testing checklist states that the test should first fail. I wonder how they managed to not test anything while seeing the tests transition from failure to success.

[bluGill]

From the GP: mock data being manually manipulated by the test gave the result of test expected.

These tests are easy to write - your mock returns something, and then you verify that the API does nothing (thus the test fails), then returns whatever the mock does and the test passes. These tests are easy to write and they do fail until code is written. However they are of negative value - you cannot refactor anything as the code only calls a mock, and returns some data from the mock.

[randomdata]

I can't imagine writing a function that is nothing more than an identity function would be easy to write (unless it was explicitly intended to be an identity function, I suppose). There must be some terrible gut wrenching feeling that goes along with it, if nothing else? Frankly, I don't understand how this situation is possible in practice, but perhaps I misunderstand what is written?

[drewcoo]

I've never seen that but I've heard the claim before.

So . . . is the team of devs who spent years writing and maintaining those tests incompetent or is it the new dev with the complaint? If it was the whole team, how did that happen?