Comment by siscia

You are not wrong but if we go deeper we will find more nuances.

> tests should test behaviour and not structure.

Of what?

The whole idea of software architecture, and underlying of my messages, is to structure the code so that it is easy, but before easy, possible, to work at the right abstraction level.

Which allows to tests the behaviour of components and not their structure.

Trivial example, say your code read from a socket and manage the bytes with some CPU operations and write them to another socket. (You may recognise it is basically what a compressor do)

The way in which you manage read and write to the sockets will make dramatically simpler or much more difficult to write good tests.

If you adopt strategies like sans-io, you will see that the testing is almost trivial.

If all the logic sprawl up from the read syscall in a loop, you will notice how more challenging testing becomes.

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To answer your question, the way I let LLMs write code is very DI (dependency injection) based.

A class never instantiates another class - all the dependencies are passed to the constructor. Including time. Including whatever DB iteraction.

The reason why I prefer this is that I can test each component at every level of abstraction. I don't have to. But I can.

My current approach is to force coverage higher than say 80% as default and then when a bug is discovered drill down to the components.