Let's talk about fixing bugs. My second favorite activity after creating them.
How do I know the bug is fixed? Well, I've been taught by wiser and more experienced people than me (way back when), that if you want to make sure the bug never shows its face again - write an automated test for it.
Ok, I admit that there were times I didn't write a test. Some fixes are so trivial, that sometimes a test is a luxury.
But even then, I was working on a hidden assumption. Just like in Fallout, code never changes. Until it does. But between those times it never changes.
I fix the bug. From this point until it actually changes by a human, or a bot or someone in-between - that code will compile, or transpile, or whatever we call "runs" the same way. A statement will execute, a condition evaluated, an exception caught - every time in the same way.
