> I have the feeling that the introduction of automatic QA may raise the bar of quality for new releases of software, and maybe partially compensate for the lower quality of the code produced at high speed with the use of automatic programming.
In theory. The only difference between today and "the aughts" is that we have machines that can spit out a ton of code very quickly.
Nothing has changed about the discipline or honesty around testing (you can skip automated tests even faster now if you wish). You can and should work with AI to write tests, but you have to know the difference between a good test and a "looks good on paper" test in order for it to truly be effective and raise the quality of what you're building.
Writing unit tests used to be the bane of my existence. I used to hate them. Often times, the LoC for unit tests was 3X the LoC of the actual code.
But not any more! Now I point the LLM to the code and order it to write unit tests, covering all edge cases, etc. I'd rather spend 3 hours arguing with the LLM than writing unit tests! :-D
Scenario testing is the new word for it and I think this is a game changer.
Two of the reasons I never liked writing tests is
- they didn’t seem to usually assert much internal logic
- they would have to be maintained along with the original code
I think scenario testing is much better instead because the actual way a person uses a feature hardly changes but the internals might change a lot.
So imagine I’m making an e-commerce website. There are lots of internal mechanisms. I’ll have an agent testing all the functionalities as if it were a customer. This gives me much much more confidence while writing code because it is more uncorellated with the code.
Tomorrow I can change a lot of internals but the testing agent stays the same.
There’s something to note though: not all code is possible to be scenario tested. Like data engineering and other things where the feedback time is huge.
Also the merits of documentation and specs. It’s been eye-opening to see the subset of developers who were almost disdainful about writing documentation for their colleagues but are now tripping over themselves to do so for their clanker.
People are rediscovering everything. Some people have proposed using a more formal language to tell the AI precisely what code to write. That's a compiler.
Are you an engineer ? You must test your "creation". Or would you expect that the microwave owen you just bougth will be tested by your child while getting burned ?
I believe this can work if done on top of traditional testing. I would feel very uneasy to replace deterministic (ok, not always but mostly) test suites with something that is not deterministic at all
I think this is just TDD or unit test dogma and I’m personally not a fan.
Unit tests and deterministic tests are hard to get right and need to be done at the correct boundary.
I have seen many people dogmatically pushing unit tests religiously but this often leads to very hard to maintain tests that mostly exist just to change along with the main code itself.
A good way to understand if your unit tests are good: are you changing them along with changing your actual code? Then it’s a bad test. I think the argument for “it’s just documentation” is weak.
I don’t disagree with your point, but there is still value in having unit tests that change along with the code. It’s less than a “proper” test, but when these tests break _unexpectedly_, it’s still more signal than you’d have without them. Like, always changing `file.go` alongside `file_test.go` may be acceptable if you catch errors that impact `serve_test.go` unexpectedly.
Of course, if you’re just watching Claude changing both and saying “LGTM” then it’s not very valuable.
13 comments:
> I have the feeling that the introduction of automatic QA may raise the bar of quality for new releases of software, and maybe partially compensate for the lower quality of the code produced at high speed with the use of automatic programming.
In theory. The only difference between today and "the aughts" is that we have machines that can spit out a ton of code very quickly.
Nothing has changed about the discipline or honesty around testing (you can skip automated tests even faster now if you wish). You can and should work with AI to write tests, but you have to know the difference between a good test and a "looks good on paper" test in order for it to truly be effective and raise the quality of what you're building.
Writing unit tests used to be the bane of my existence. I used to hate them. Often times, the LoC for unit tests was 3X the LoC of the actual code.
But not any more! Now I point the LLM to the code and order it to write unit tests, covering all edge cases, etc. I'd rather spend 3 hours arguing with the LLM than writing unit tests! :-D
Scenario testing is the new word for it and I think this is a game changer.
Two of the reasons I never liked writing tests is
- they didn’t seem to usually assert much internal logic
- they would have to be maintained along with the original code
I think scenario testing is much better instead because the actual way a person uses a feature hardly changes but the internals might change a lot.
So imagine I’m making an e-commerce website. There are lots of internal mechanisms. I’ll have an agent testing all the functionalities as if it were a customer. This gives me much much more confidence while writing code because it is more uncorellated with the code.
Tomorrow I can change a lot of internals but the testing agent stays the same.
There’s something to note though: not all code is possible to be scenario tested. Like data engineering and other things where the feedback time is huge.
are we just re-inventing playwright tests except 10x slower and infinity times more expensive?
i feel like im going insane
since the rise of agentic coding tools, it feels like we're in a new "eternal september" of people discovering ui end-to-end test automation.
Also the merits of documentation and specs. It’s been eye-opening to see the subset of developers who were almost disdainful about writing documentation for their colleagues but are now tripping over themselves to do so for their clanker.
People are rediscovering everything. Some people have proposed using a more formal language to tell the AI precisely what code to write. That's a compiler.
>Scenario testing is the new word
How is scenario different from a behavior (as in Behavior-Driven Development)?
Gherkin and things like Cucumber are not something new, are they?
> Two of the reasons I never liked writing tests
Are you an engineer ? You must test your "creation". Or would you expect that the microwave owen you just bougth will be tested by your child while getting burned ?
'I never liked writing tests' is not the same as 'I don't write tests'.
I believe this can work if done on top of traditional testing. I would feel very uneasy to replace deterministic (ok, not always but mostly) test suites with something that is not deterministic at all
I think this is just TDD or unit test dogma and I’m personally not a fan.
Unit tests and deterministic tests are hard to get right and need to be done at the correct boundary.
I have seen many people dogmatically pushing unit tests religiously but this often leads to very hard to maintain tests that mostly exist just to change along with the main code itself.
A good way to understand if your unit tests are good: are you changing them along with changing your actual code? Then it’s a bad test. I think the argument for “it’s just documentation” is weak.
I don’t disagree with your point, but there is still value in having unit tests that change along with the code. It’s less than a “proper” test, but when these tests break _unexpectedly_, it’s still more signal than you’d have without them. Like, always changing `file.go` alongside `file_test.go` may be acceptable if you catch errors that impact `serve_test.go` unexpectedly.
Of course, if you’re just watching Claude changing both and saying “LGTM” then it’s not very valuable.