How to Debug Ruby on Rails

Can you tell me how to debug Ruby on Rails?

A fast and easy solution might be installing the ruby-debug gym.

Gems are code modules.

And ruby-debug is like the spell check of Ruby code, helping you find the really obvious errors.

If they were obvious, I wouldn’t be asking for help now.

Once you install ruby-debug, you install the cheat sheet gem before running rails via RDEBUG.

I might not be able to figure out which lines of code it is tripping over.

That’s why you add break points to your code, so that you have to hit a key to progress but you know that an error is in the lines after the last breakpoint if the debugger finds one.

How do I add a breakpoint?

In Ruby, that’s b line. Use N for next, C for continue and other commands like the Perl debug.

Smart little bugger.

If you’re in Ruby on Rails, you launch the debugger from the server with the script/server –debugger command.

I’ve never heard of RDEBUG before.

You could use Pry. That’s on GitHub.

Ruby NPM is on GitHub, too.

Everything for Ruby on Rails is on GitHub short of any code you create.

Can I put my code there for others to debug?

You can save your code to GitHub and run collaborative projects through the site, but you can’t ask others to debug what you upload there for free. But you could check stackoverflow.com for other programmer’s advice on what to do.

Any other ideas on how to debug Ruby code?

Turn warnings on so you can actually see what Ruby is trying to tell you about the errors as it runs. For example, you’ll get errors for uninitialized variables that may make it obvious where you went wrong.

I heard about using printing.

Print debugging is its own discussion, but you’ve got lots of other ways to find the bugs in your code.

I hope something works, because this is driving me buggy.