https://github.com/cldwalker/debugger
gem install debugger
In ~/.rdebugrc (You'll want to set these)
set autolist
set autoeval
set autoreload
In the location you want to debug, add the following line:
require 'debugger'; debugger; puts 'stay';
(The puts 'stay' is not technically required, but is useful if you are placing the debugger at the end of a block.)
While debugging, or in your IRB/Rails console, the following methods may be helpful:
object.instance_variables
object.instance_variable_get("@name_of_variable")
Class.constants
object.methods.grep(/regexp_for_method/)
object.method(:method_name).source_location # Ruby 1.9
https://github.com/ryanlecompte/method_locator
gem install method_locator
object.methods_for(:method_name)
An array of each defintion for that object's method.
object.methods_for(:method_name).each {|m| puts "#{m.source_location.first}:#{m.source_location.last}" }
The above prints the location of all method definitions for the given object's method.
object.method_lookup_path
An array of all of the classes and modules that compose the object.
Where is the gem I am using located on my machine
$ bundle show <gemname>
Open the gem in my editor
$ bundle open <gemname>
https://blog.engineyard.com/2013/bundler-hacking
$ gem server or $ bundle exec gem server
Go to http://0.0.0.0:8808/ and view all of the gems, their locations and descriptions. If you installed the gems with RDoc, then you will also have access to the RDocs.
I hope you are using git.
Find when an error was introduced:
$ git bisect
Have a test script that exits status 0 on success; and not 0 on failure
- This could be a test script in your project or an external script
Mark one commit as good and another as bad, then run bisect.
- It will point out exactly which commit broke your test script
- As an aside, keep your git commits as small as possible, with each commit being a single concern.
http://www.askbjoernhansen.com/2010/04/30/git_bisect_mini_tutorial.html
A demo that you run from command line, walking through a handful of git commands, performing actions on a repo it creates:
https://github.com/jeremyf/git-demo
https://github.com/michaeldv/awesome_print
You may appreciate formatted output in IRB