> if you are good enough to write perfect tests for your code, just write perfect code. If you aren’t perfect at writing tests, how do you know the tests are complete, bug free, and actually useful?
This sentence makes no sense. Tests are infinitely more straightforward than code. I always go back to my dad's work as a winder before he retired:
After repairing a generator, they'd test it can handle the current that it's expected to take by putting it in a platform and... running electricity through it. They'd occasionally melt all the wiring on the generator and have to rewind it.
By your logic, since they weren't "good enough" to fix it perfectly, how could they know their test even worked? Should they have just shipped the generator back to the customer without testing it?
> if you are good enough to write perfect tests for your code, just write perfect code. If you aren’t perfect at writing tests, how do you know the tests are complete, bug free, and actually useful?
This was the original quote. Just because one aspect of a system is difficult to test doesn't make this quote true.
> No, they often aren't, and UI can be complex to test.
It can be but I've seen different ways to get confidence through testing. Just because it's complex doesn't mean we shouldn't do things to improve our confidence that what we're building works.
Go back to my example above: I guarantee that a repair has been tested, returned to the customer and failed the test after it was fitted. Why? The fault was elsewhere. But testing gave him confidence the generator wasn't the source of the problem.
This sentence makes no sense. Tests are infinitely more straightforward than code. I always go back to my dad's work as a winder before he retired:
After repairing a generator, they'd test it can handle the current that it's expected to take by putting it in a platform and... running electricity through it. They'd occasionally melt all the wiring on the generator and have to rewind it.
By your logic, since they weren't "good enough" to fix it perfectly, how could they know their test even worked? Should they have just shipped the generator back to the customer without testing it?