Spring is a Rails application preloader. When debugging e.g. the rails gem, you'll be wondering why your raise, puts or debugger debugging statements have no effect. That's because Spring preloads and caches your application once and all consecutive calls to it will not see any changes in your debugged gem.

Howto

Disable spring with export DISABLE_SPRING=1 in your terminal. That will keep Spring at bay in that terminal session.

In Ruby, [you can only write environment variables that subproc...

MenuetOS is an Operating System in development for the PC written entirely in 32/64 bit assembly language. Menuet64 is released under License and Menuet32 under GPL. Menuet supports 32/64 bit x86 assembly programming for smaller, faster and less resource hungry applications.

• Fits on a single floppy, boots also from CD and USB drives
• Responsive GUI with resolutions up to 1920x1080, 16 million colours
• Free-form, transparent and skinnable application windows, drag'n drop
• SMP multiprocessor support with currently up to 8 cpus
• IDE: E...

General

Programatically invoke Rails generators

Require the generator, instantiate it and invoke it (because generators are Thor::Groups, you need to invoke them with invoke_all). Example:

 require 'generators/wheelie/haml/haml_generator'
 Generators::HamlGenerator.new('argument').invoke_all

Other ways: Rails invokes its generators with Rails::Generators.invoke ARGV.shift, ARGV. From inside a Rails generator, you may call the [inherited Thor method invoke(args=[], options={}, config={})](https://github...

docopt helps you define interface for your command-line app, and automatically generate parser for it.

docopt is based on conventions that are used for decades in help messages and man pages for program interface description. Interface description in docopt is such a help message, but formalized. Here is an example:

Naval Fate.

Usage:
  naval_fate ship new <name>...
  naval_fate ship <name> move <x> <y> [--speed=<kn>]
  naval_fate ship shoot <x> <y>
  naval_fate mine (set|remove) <x> <y> [--moored|--drifting]
  naval_fate -h |...

If you regularly get ActionView::MissingTemplate exceptions, maybe some bot visits your site requesting silly formats like:

http://www.rails-app.com/makandra.html-username-2000 # => Rails tries to retrieve 'makandra' with format 'html-username-2000'

Just restrict accepted format parameters for the whole application like this:

class ApplicationController < ActionController::Base

  before_filter :refuse_silly_formats

  private

  def refuse_silly_formats
    acceptable_formats = %w[html xml pdf]

    if par...

If you are using Angular and want something like Rails' simple_format which HTML-formats a plain-text input into paragraphs and line breaks, this directive is for you.

Any HTML fragments inside that text will still be escaped properly.

Use it like this, where your text attribute specifies something available in your current scope:

<simple-format text="email.message"></simple-format>

This is the directive, in CoffeeScript syntax:

@app.directive 'simpleFor...

If you want to do JavaScript-style camelization, ActiveSupport's String#camelize method can actually help you out. Simply pass a :lower argument to it.

>> 'foo_bar_baz'.camelize
=> "FooBarBaz"
>> 'foo_bar_baz'.camelize(:lower)
=> "fooBarBaz"

If you come across an (older) application that is using Prototype instead of jQuery, you may often see events bound to single elements only, like this:

$('foo').observe('change', updateThings);
$('bar').observe('change', updateThings);
$('baz').observe('change', updateThings);

If you are calling only one method in each case, this is unnecessarily ugly. Also, when your page contents have been replaced via AJAX (like sections of a form after choosing something), those event hooks will no longer wo...

When using TextMate2 with the cucumber bundle, it does not recognize step definitions (e.g. custom_steps.rb) as such but believes they are plain Ruby files. But there is help!

Solution

Add these lines to the bottom of your .tm_properties file (in ~/ for global settings, in any directory for per-project settings):

[ "*_steps.rb" ]
fileType = "source.ruby.rspec.cucumber.steps"

Apparently, this works for any files. Define a regex and specify custom settings. The attached article lists all available configuration options (whic...

We now have a gem that supports our form model approach.

How to remove/disable the automatic XSS protection helper html escaping for Rails 3.

This is probably a horrible idea.

Alternatives to drop-down menus to consider in form design.

Did you know?

rake stats # => LOC per controllers, models, helpers; code ratios, and more
rake notes # => collects TODO, FIXME and other Tags from comments and displays them
rake about # (Rails 3+) => Rails, Ruby, Rake, Rack etc. versions, used middlewares, root dir, etc.

I had to deal with JavaScript Undefined Error while accessing a specific CKEditor instance to fill in text.

Ensure everything is loaded with

patiently do
  page.execute_script("return isCkeditorLoaded('#{selector}');").should be_true
end

Example

The fill in text snippet for Cucumber:

When /^I fill in the "([^\"]+)" WYSIWYG editor with:$/ do |selector, html|
  patiently do
    page.execute_script("return isCkeditorLoaded('#{selector}');").should be_true
  end
  html.gsub!(/\n+/, "") # otherwise: unterminated string lit...

Ask before leaving an unsaved CKEditor

Vanilla JavaScript way, but removes any other onbeforeunload handlers:

  $(function(){
    document.body.onbeforeunload = function() {
      for(editorName in CKEDITOR.instances) {
        if (CKEDITOR.instances[editorName].checkDirty()) {
          return "Unsaved changes present!"
        }
      }
    }
  }

A robuster implementation example

Note: Don't forget to mark the 'search as you type' forms with the skip_pending_changes_warning class.

var WarnBeforeAccidentallyDiscard...

If you have a text that is edited by WSYIWYG-Editor but want some length checking nevertheless, you need to strip all tags and then the special characters:

  def hard_sanitize(text)
    ActionController::Base.helpers.strip_tags(text).gsub(/[^[:word:]]+/, " ")
  end

   :001 > hard_sanitize("This is <strong>beautiful</strong> <h1>markup<h1>")
   => "This is beautiful markup" 

If you allready have nokogiri on board, you can use that as well, though it has no extra benefit:

   :001 > Nokogiri::HTML("This is <strong>beau...

After I upgraded to Mac OS X Mavericks, I regularly got this error message when running Cucumber features with Selenium:

Element cannot be scrolled into view:[object XrayWrapper [object HTMLInputElement]] (Selenium::WebDriver::Error::MoveTargetOutOfBoundsError)

I had the Terminal window running the test on my secondary screen, whereas the Selenium-webdriven Firefox always started on my primary one. Now if I had focused the secondary screen when running the tests, Selenium could not start Firefox and switch to it (probably because t...

Warning: Because of (unclear) rounding issues and missing decimal places (see examples below),
do NOT use this when dealing with money. Use our amount helper instead.

In Ruby, you can easily format strings using % (short for Kernel#sprintf):

'%.2f' % 1.23456 #=> 1.23
'%.2f' % 2 #=> 2.00

However, what if you only want the decimals to be shown if they matter? There is g! It will limit the total number of displayed digits, disregarding...

Alternative approach to form models.

Great slide deck about various forms of refactorings.

If you have a FooController and also have a layout app/views/layouts/foo.html, Rails will use this without being told so.

This is super convenient except never.

TLDR: This card explains which threads and processes interact with each other when you run a Selenium test with Capybara. This will help you understand "impossible" behavior of your tests.

When you run a Rack::Test (non-Javascript) test with Capybara, there is a single process in play. It runs both your test script and the server responding to the user interactions scripted by your test.

A Selenium (Javascript) test has a lot more moving parts:

1. One process runs your test script. This is the process you...