paper_trail is an excellent gem to track record versions and changes.

You almost never want to reimplement something like it yourself. If you need to log some extra information, you can add them on top.

It comes with a really good README file that holds lots of examples. I'll show you only some of its features here:

• Setting up a model to track changes

  Just add has_paper_trail to it:
  class User < ActiveRecord::Base
  has_paper_trail
  end

• Accessing a previous version

  Saying user.previous_version gi...

When we looked at this card together a year ago, we were no longer sure if unquote is actually useful. I now found a good example for when you need unquote, and rewrote the card accordingly.

The will_paginate gem will show a default of 30 records per page.
If you want to test pagination in a Cucumber feature, you don't want to create 31 records just for that.

Instead, you probably want to modify the number of items shown, by saying something like this:

Given we paginate after 2 users

Using the following step definition, you now can! :)

require 'cucumber/rspec/doubles'

Given /^paginate after (\d+) (.*)$/ do |per_page, model_name|
  model = model_name.singularize.gsub(/...

The $.cssHooks object provides a way to define functions for getting and setting particular CSS values. It can also be used to create new cssHooks for normalizing CSS3 features such as box shadows and gradients.

For example, some versions of Webkit-based browsers require -webkit-border-radius to set the border-radius on an element, while earlier Firefox versions require -moz-border-radius. A css hook can normalize these vendor-prefixed properties to let .css() accept a single, standard property name (border-radius, or with DOM property synt...

• The step we used in the past (Then "foo" should not be visibile) doesn't reliably work in Selenium features.
• I overhauled the entire step so it uses Javascript to detect visibility in Selenium.
• The step has support for jQuery and Prototype projects, so it should be a drop-in replacement for all your projects.
• For Rack::Test the step no longer uses XPath so you should be able to understand it when you are not a cyborg :)
• There were some other cards detailing alternative steps to detect visibility. I deleted all these other cards s...

I highly recommend that you make use of RubyMine's feature to pin tabs.

When you pin all "important" files, you can follow method definitions, wildly open files from search results and have a ton of open tabs -- without the problem of finding the stuff you were working on before.

Guide

1. Pin the tabs of files that are currently in the focus of your work (important models, specs, etc):
   • Right-click a tab and select "Pin tab"
   • Or use a shortcut (see below)
2. Work as usual.
3. Once you opened other tabs because you searched ...

When you use method_missing to have an object return something on a method call, always make sure you also redefine respond_to_missing?.

If you don't do it, nothing will break at a first glance, but you will run into trouble eventually.

Consider this class:

class Dog
  
  def method_missing(method_name, *args, &block)
    if method_name == :bark
      'woof!'
    else
      super
    end
  end
  
end

This will allow you to say:

Dog.new.bark
=> "woof!"

But:

Dog.new.respond_to? :bark
=> false
```...

Applications often show or hide elements based on viewport dimensions, or may have components that behave differently (like mobile vs desktop navigation menus).
Since you want your integration tests to behave consistently, you want to set a specific size for your tests' browser windows.

Using WebDriver options / Chrome device metrics

For Google Chrome, the preferred way is setting "device metrics". This allows you to configure dimensions larger than your display and enable/disable touch behavior.

Simply use register_driver to set up...

You can specify the version of bundler to execute a command (most often you need an older version of bundler, but don't want to uninstall newer ones):

bundle _1.0.10_ -v
Bundler version 1.0.10

An example is rails 3.2, which freezes bundler at version ~> 1.0:

Bundler could not find compatible versions for gem "bundler":
  In Gemfile: rails (~> 3.2) was resolved to 3.2.0, which depends on bundler (~> 1.0)

Current Bundler version: bundler (1.13.6)

You can solve this with:

gem install bundler -v 1....

When you are scrolling up to investigate a test failure it is super annoying when the terminal scrolls back down whenever the running test outputs another line. Luckily you can disable this behavior:

• Gnome terminal: *Edit -> Profile preferences -> Scrolling", uncheck Scroll on output
• Terminator: Right click on terminal screen, Preferences -> Profile -> (for each profile) -> Scrolling, uncheck Scroll on output

Updated the card with our current best practice (shared app code and specs via symlinks).

If you use rails_admin, your specs pass with the rspec binary, but not using rake spec (or rake parallel:spec etc), put this at the top of your spec_helper:

ENV['SKIP_RAILS_ADMIN_INITIALIZER'] = 'false'

Don't ask.

This is probably also true for cucumber, your env.rb would be the right place.

RSpec's be_false behaves unexpectedly:

nil.should be_false
# passes, as the expectation returns true

If you want to check for false, you need to do it like this:

nil.should == false
# fails as expected

Wat?

See also

RSpec: be_true does not actually check if a value is true

Ruby 1.9.2 is very slow when loading files, especially starting Rails servers or running specs takes forever.

Do yourself a favor and upgrade to 1.9.3.

Note that this seems to affect only recent Rails 2 versions.

You will not encounter this until you are writing to the cookie more than once, but when doing so, integration tests (Cucumber) may break for you with this error:

You have a nil object when you didn't expect it!
You might have expected an instance of ActiveRecord::Base.
The error occurred while evaluating nil.[] (NoMethodError)

Background

The regular/short cucumber backtrace is not of any help but looking at the full trace reveals that ActionPack's `actio...

The Rails community has been abuzz with object-oriented programming, SOLID principles, laws, design patterns, and other principles, practices, and patterns. We’ve (re)discovered new tools and techniques to separate and reuse logic, making code easier to test, understand, and maintain. Now that we’ve learned about all these new tools, when do we use them?

Recent rails security updates have shown that people make incorrect assumptions about the possible contents of the params hash.

Just don't make any! Treat it as what it is: potentially unsafe user input. For example:

/pages/edit?foo=   --> params == {:foo => ""}
/pages/edit?foo    --> params == {:foo => nil}
/pages/edit?foo[]  --> params == {:foo => [nil]} # at least in older rails 3 and in rails 2.x

Be especially wary about stuff like

User.find_by_password_reset_token(params[:password_reset_token])

I...

Why string sorting sucks in vanilla Ruby

Ruby's sort method doesn't work as expected with special characters (like German umlauts):

["Schwertner", "Schöler"].sort
# => ["Schwertner", "Schöler"] # you probably expected ["Schöler", "Schwertner"]

Also numbers in strings will be sorted character by character which you probably don't want:

["1", "2", "11"].sort
# => ["1", "11", "2"] # you probably expected ["1", "2", "11"]

Also the sorting is case sensitive:

...

The problem

When using the asset pipeline your assets (images, javascripts, stylesheets, fonts) live in folders inside app:

app/assets/fonts
app/assets/images
app/assets/javascripts
app/assets/stylesheets

With the asset pipeline, you can use the full power of Ruby to generate assets. E.g. you can have ERB tags in your Javascript. Or you can have an ERB template which generates Haml which generates HTML. You can chain as many preprocessors as you want.

When you deploy, Rails runs assets:precompile...

Some progress was made by browsers on implementing CSS filters like blur, greyscale or some other effects. You might already know the legacy CSS filter attribute that old IE versions used to perform DirectX transformations. Luckily these legacy filters are removed in IE10. The good news is, newest WebKit-based browsers like Chrome (18.0+) Safari and Mozilla Firefox expe...

If you are using VNC to run Selenium tests, it may be hard to see what's going on since by default there is no list of open windows and Alt+Tab won't work.

Solving that is easy:

1. Install a panel of your choice (like lxpanel) which offers task switching:

   sudo apt-get install lxpanel
   

   (You can't use gnome-panel because it won't start twice -- but lxpanel does a good job)

2. To have that panel appear on VNC screens by default, edit ~/.vnc/xstartup...