Survey: a third of senior developers say over half their code is AI-generated

In terms of LOCs maybe, in terms of importance I think is much less. At least that's how I use LLMs.

While I understand that <Enter model here> might produce the meaty bits as well, I believe that having a truck factor of basically 0 (since no-one REALLY understands the code) is a recipe for a disaster and I dare say long term maintainability of a code base.

I feel that you need to have someone in any team that needs to have that level of understanding to fix non trivial issues.

However, by all means, I use the LLM to create all the scaffolding, test fixtures, ... because that is mental energy that I can use elsewhere.

Agreed. If I use an LLM to generate fairly exhaustive unit tests of a trivial function just because I can, that doesn’t mean those lines are as useful as core complex business logic that it would almost certainly make subtle mistakes in.

> If I … generate fairly exhaustive unit tests of a trivial function

… then you are not a senior software engineer

Neither are you if that's your understanding of a senior engineer

I think the parent commentors point was that it is nearly trivial to generate variations on unit tests in most (if not all) unit test frameworks. For example:

Java: https://docs.parasoft.com/display/JTEST20232/Creating+a+Para...

C# (nunit, but xunit has this too): https://docs.nunit.org/articles/nunit/technical-notes/usage/...

Python: https://docs.pytest.org/en/stable/example/parametrize.html

cpp: https://google.github.io/googletest/advanced.html

A belief that the ability of LLMs to generate parameterizations is intrinsically helpful to a degree which cannot be trivially achieved in most mainstream programming languages/test frameworks may be an indicator that an individual has not achieved a substantial depth of experience.

The useful part is generating the mocks. The various auto mocking frameworks are so hit or miss I end up having to manually make mocks which is time consuming and boring. LLMs help out dramatically and save literally hours of boring error prone work.

Why mock at all? Spend the time making integration tests fast. There is little reason a database, queue, etc. can't be set up in a per-test group basis and be made fast. Reliable software is built upon (mostly) reliable foundations.

Because if part of my tests involve calling an OpenAI endpoint, I don't want to pay .01 cent every time I run my tests.

Because my tests shouldn't fail when a 3rd party dependency is down.

Because I want to be able to fake failure conditions from my dependencies.

Because unit tests have value and mocks make unit tests fast and useful.

Even my integration tests have some mocks in them, especially for any services that have usage based pricing.

But in general I'm going to mock out things that I want to simulate failure states for, and since I'm paranoid, I generally want to simulate failure states for everything.

End to End tests are where everything is real.