I have experience with AI generated test suites, and while its good for generating coverage, it isn’t so good for actually ensuring correctness, which is the actual point.
I’ve watched the robot happily introduce bugs to pass broken tests, and also break tests to match code, and everything in between.
You have to prompt for that, I do that regularly along with refactors. ‘Examine all tests to ensure they are testing functionality and not just passing a test.’ It finds them and will work on it. I think the problem continues to be engineering discipline. People are lazy with AI on multiple levels, not just copy pasta slop.
This code is clearly functional, it’ll compile and execute.
However, the customer actually needs the code to do a saturating add.
With that knowledge, we can clearly see that the code is not correct. It will not saturate, it will wrap around instead.
Without that knowledge, an LLM will happily write some basic unit tests that won’t cover the saturation edge case, and the bug would live on until its hit in prod.
If you’re lucky, and your function doco is good, the LLM might spot the bug, and notify you.
My personal preference for how to generate tests is to ask the agent to write specific tests. E.g: “write a test for add that demonstrates that it saturates”.
Yeah, I had testers that tested the functionality of a delay… But had set the delay parameter to zero. Well good thing this one case worked, but you didn’t check anything beyond that for correctness at all.
We continuously create tests that ensure a process completes in an set amount of time, and every time, we don’t give them enough leeway, and the test will fail randomly if the CI runner gets overloaded.
Interested in how much actual experience you have with AI geneated testsuites.
My code was never tested this well.
I have experience with AI generated test suites, and while its good for generating coverage, it isn’t so good for actually ensuring correctness, which is the actual point.
I’ve watched the robot happily introduce bugs to pass broken tests, and also break tests to match code, and everything in between.
I don’t want lots of tests, I want good tests.
You have to prompt for that, I do that regularly along with refactors. ‘Examine all tests to ensure they are testing functionality and not just passing a test.’ It finds them and will work on it. I think the problem continues to be engineering discipline. People are lazy with AI on multiple levels, not just copy pasta slop.
Testing functionality isn’t the same as correctness.
Oh excuse me then, what is correctness?
int add(int a, int b) { return a + b; }This code is clearly functional, it’ll compile and execute.
However, the customer actually needs the code to do a saturating add.
With that knowledge, we can clearly see that the code is not correct. It will not saturate, it will wrap around instead.
Without that knowledge, an LLM will happily write some basic unit tests that won’t cover the saturation edge case, and the bug would live on until its hit in prod.
If you’re lucky, and your function doco is good, the LLM might spot the bug, and notify you.
My personal preference for how to generate tests is to ask the agent to write specific tests. E.g: “write a test for add that demonstrates that it saturates”.
Yeah, I had testers that tested the functionality of a delay… But had set the delay parameter to zero. Well good thing this one case worked, but you didn’t check anything beyond that for correctness at all.
Timing and tests, name a better migraine duo :D.
We continuously create tests that ensure a process completes in an set amount of time, and every time, we don’t give them enough leeway, and the test will fail randomly if the CI runner gets overloaded.