Tattletail

Introduction

Tattletail is a simple ruby debugging tool that provides Rubyists a way to tattle on methods.

Similar to 'poor mans' debugging with puts statements, Tattletail outputs whenever the method you tattle on gets called.

In addition, Tattletail will give you:

• A call chain tree
• The name of the method
• The instance id of the method's object
• The parameters passed into the method
• The location of the Ruby file (and line number) from whence the method was called
• A benchmark of the method's execution time

Requirements

You need Ruby 1.9.2.

Tattletail is a work in progress and has not been known to work on rubies other than 1.9.2.

Installation

Installing Tattletail is easy:

gem install tattletail

Usage

Using Tattletail has two steps:

1. Load it into your environment.
2. tattle_on a method.

Load it into your environment with:

require 'tattletail'

Or, place it in your gemfile.

gem 'tattletail'

tattle_on a method by simply adding tattle_on <method_name> somewhere in your class.

Example:

Say we have a class that looks like this:

class Sequences
  def fibonacci n
    return 1 if n <= 2
    fibonacci(n - 1) + fibonacci(n - 2)
  end
end

And we wonder why it gets called so often, so we tattle on the fibonacci method.

class Sequences
  def fibonacci n
    return 1 if n <= 2
    fibonacci(n - 1) + fibonacci(n - 2)
  end
  tattle_on :fibonacci
end

Then we call this method in irb (or better yet pry):

pry(main)> Sequences.new.fibonacci 4

And Tattletail outputs:

─┬─ #1 #<Sequences:0x007fa8eaa79960>.fibonacci(4) called
 │         /gems/tattletail-0.0.3/lib/tattletail/demo.rb:18
 │
 ├──┬─ #2 #<Sequences:0x007fa8eaa79960>.fibonacci(3) called
 │  │         /gems/tattletail-0.0.3/lib/tattletail/demo.rb:18
 │  │
 │  ├──┬─ #3 #<Sequences:0x007fa8eaa79960>.fibonacci(2) called
 │  │  │         /gems/ruby-1.9.2-p290@tattletail/gems/tattletail-0.0.3/lib/tattletail/demo.rb:18
 │  │  └─ #3 #<Sequences:0x007fa8eaa79960>.fibonacci(2) ⊢ 1
 │  │         0.0000 sec
 │  │
 │  ├──┬─ #4 #<Sequences:0x007fa8eaa79960>.fibonacci(1) called
 │  │  │         /gems/ruby-1.9.2-p290@tattletail/gems/tattletail-0.0.3/lib/tattletail/demo.rb:18
 │  │  └─ #4 #<Sequences:0x007fa8eaa79960>.fibonacci(1) ⊢ 1
 │  │         0.0001 sec
 │  │
 │  └─ #2 #<Sequences:0x007fa8eaa79960>.fibonacci(3) ⊢ 2
 │         0.0017 sec
 │
 ├──┬─ #5 #<Sequences:0x007fa8eaa79960>.fibonacci(2) called
 │  │         /gems/ruby-1.9.2-p290@tattletail/gems/tattletail-0.0.3/lib/tattletail/demo.rb:18
 │  └─ #5 #<Sequences:0x007fa8eaa79960>.fibonacci(2) ⊢ 1
 │         0.0000 sec
 │
 └─ #1 #<Sequences:0x007fa8eaa79960>.fibonacci(4) ⊢ 3
        0.0029 sec

More Information

Issues? Questions? Open an Issue on github.

If you need more usage examples, they can be found in lib/tattletail/demo.rb

Contributing

Want to contribute? Great!

1. Fork it.
2. Create a branch (git checkout -b my_feature).
3. Commit your changes (git commit -am "Added Awesomeness").
4. Push to the branch (git push origin my_feature).
5. Create an Issue with a link to your branch.
6. Enjoy a refreshing Diet Coke and wait.