For most of my career I thought there was always something missing with how I debugged, like I needed to set-up an advanced error reporting system that would log and track down every error seamlessly. Then, I would really know how to debug like a 1337 haxor.
Now that I have a big kid job, how has my debugging system evolved to be more professional?
The same things I did when I started, I still do. I still
console.log things. I still
print_r() arrays to see what’s going on. Even in extremely complex codebases and systems, the same ideas work.
Debugging is Problem Solving
What I understand now is that
var_dump isn’t debugging. Those are tools to help you debug. The real debugging happens with you.
I don’t consciously go through this checklist, but this is the general idea of how I debug.
Recreate the bug.
Can you reliably reproduce the bug? If you don’t know what environments and situations it happens in, it’s extremely hard to debug. Is it a certain browser? A certain device? Does it happen consistently after a certain action?
Check your assumptions.
Is that variable really what I think it is? Does that function really return what I think it does? This is where I will
console.log stuff, or code directly in the console to test basic functions and methods to make sure I really understand what does happen vs what is supposed to happen.
Reduce the scope of your issue to the tiniest bit of code you can. If you’re working on a complex CSS issue, how can you boil it down to the most basic test case possible?
If you’re not able to isolate the issue and reliably reproduce it, then you don’t really understand what the fix is. CodePen is great for helping with this, as you can isolate in a clean environment and then share results with your team.
There’s nothing incredible or advanced about debugging. It’s just about being persistent to understand the root cause of the issue. Some bugs take a long time, but the more you poke and prod at it, the more you’ll understand it.
You’re Debugging. Not the Tools.
Remember, you’re the one doing the debugging. To put it all together, we’ve got:
- Recreate the bug.
- Check your assumptions.
- Be persistent
We can easily remember this with RCIB, or BIRC, or hrmm.. CRIB? I bet you’ll be OK without an acronym, there are already enough things to remember.
The tools assist you, and can help guide you to the issue. In the end, you’re the one solving the problem, so use whatever tools you want to help you. 🙌