Listing only deleted files between master and a given branch in git

git diff --name-status master..some-branch-name | sed '/^M/ d' | sed '/^A/ d' | mate

Could not find 'railties' (>= 0) among 46 total gems

This happened in a Rails 5 alpha installation. Use:

bundle exec rails -v
bundle exec rails c

to resolve this issue.

Rails 5 Quickly Book

I am updating my Rails 4.2 Quickly book to Rails 5. If you want to read it online, here are the links:

Chapter 1 : Running the Server
Chapter 2 : Hello Rails
Chapter 3 : Model
Chapter 4 : Model View Controller
Chapter 5 : View to Model
Chapter 6 : Update Article
Chapter 7 : Show Article
Chapter 8 : Delete Article
Chapter 9 : View Duplication
Chapter 10 : Relationships
Chapter 11 : Delete Comment
Chapter 12 : Restricting Operations

For initial setup, checkout this article : Creating a Rails 5 Project

JSON::ParserError:

JSON::ParserError:
       757: unexpected token at

Solution:

Escape the double quotes:
"{\"foo\":\"bar\"}"

`class_exec': no block given (LocalJumpError)

This happens in Rspec if you miss the it() method. For example:

describe Car
   expect(Car.speed).to eq(0)
end

The error message is not beginner friendly and can be improved.

Killing the process running on a given port on Mac OS 10.10.5

$ lsof -i tcp:3000

$ kill -9

Rename all .css.scss to .scss file

Stolen script to make upgrade to Rails 4.2 easier: Save it as .sh file, run chmod 755 renamer.sh

#! /usr/bin/env bash
	for f in $(find . -type f -iname '*.css.scss'); do
	renamed=$(echo "${f}" | sed 's/.css.scss$/.scss/g')
	cmd="git mv ${f} ${renamed}"
	echo $cmd
	eval $cmd
	done

Wait for External calls to finish

Note to myself: Create an utility similar to this : https://robots.thoughtbot.com/automatically-wait-for-ajax-with-capybara to fix the sleep hack in Stripe project.

# spec/support/wait_for_external_call.rb
module WaitForExternalCall
  def wait_for_remote_call
    Timeout.timeout(Capybara.default_wait_time) do
      loop until custom_assertion_passed?
    end
  end

  def custom_assertion_passed?
   
  end
end

RSpec.configure do |config|
  config.include WaitForExternalCall, type: :feature
end

How to set default editor for bundle open

 export BUNDLER_EDITOR='mate'

Testing Tip

Instead of checking each attribute of a JSON response in your test, you can use json-schema for api validation. Use jsonschema.net to generate a valid JSON schema from a valid sample data. You can delete all the links that point to jsonschema.net and save the json file in the fixtures directory.

Could not find 'railties' (>= 0) among 46 total gem(s) (Gem::LoadError) in Rails 5 Project

Problem

zepho-mac-pro:rails5 zepho$ rails -v
/Users/zepho/.rvm/rubies/ruby-2.2.3/lib/ruby/2.2.0/rubygems/dependency.rb:315:in `to_specs': Could not find 'railties' (>= 0) among 46 total gem(s) (Gem::LoadError)
Checked in 'GEM_PATH=/Users/zepho/.rvm/gems/ruby-2.2.3@r5blog:/Users/zepho/.rvm/gems/ruby-2.2.3@global', execute `gem env` for more information
from /Users/zepho/.rvm/rubies/ruby-2.2.3/lib/ruby/2.2.0/rubygems/dependency.rb:324:in `to_spec'
from /Users/zepho/.rvm/rubies/ruby-2.2.3/lib/ruby/2.2.0/rubygems/core_ext/kernel_gem.rb:64:in `gem'
from /Users/zepho/.rvm/gems/ruby-2.2.3@r5blog/bin/rails:22:in `

'

Fix:

zepho-mac-pro:rails5 zepho$ bundle check
Resolving dependencies...
The Gemfile's dependencies are satisfied
zepho-mac-pro:rails5 zepho$ gem list rails

*** LOCAL GEMS ***

jquery-rails (4.0.5)
rails-deprecated_sanitizer (1.0.3)
rails-dom-testing (1.0.7)
rails-html-sanitizer (1.0.2)
sprockets-rails (2.3.3)
zepho-mac-pro:rails5 zepho$ gem list railties

*** LOCAL GEMS ***


zepho-mac-pro:rails5 zepho$ gem install rails
Fetching: rack-1.6.4.gem (100%)
Successfully installed rack-1.6.4
Fetching: activesupport-4.2.5.gem (100%)
Successfully installed activesupport-4.2.5
Fetching: actionview-4.2.5.gem (100%)
Successfully installed actionview-4.2.5
Fetching: actionpack-4.2.5.gem (100%)
Successfully installed actionpack-4.2.5
Fetching: railties-4.2.5.gem (100%)
Successfully installed railties-4.2.5
Fetching: activejob-4.2.5.gem (100%)
Successfully installed activejob-4.2.5
Fetching: actionmailer-4.2.5.gem (100%)
Successfully installed actionmailer-4.2.5
Fetching: arel-6.0.3.gem (100%)
Successfully installed arel-6.0.3
Fetching: activemodel-4.2.5.gem (100%)
Successfully installed activemodel-4.2.5
Fetching: activerecord-4.2.5.gem (100%)
Successfully installed activerecord-4.2.5
Fetching: rails-4.2.5.gem (100%)
Successfully installed rails-4.2.5
11 gems installed
zepho-mac-pro:rails5 zepho$ rails -v
Rails 5.0.0.alpha

Creating a Rails 5 Project

1. Create a Gemfile

source "https://rubygems.org"

ruby '2.2.3'

gem 'rack', github: 'rack/rack'
gem 'rails', git: 'git://github.com/rails/rails.git'
gem 'arel', git: 'git://github.com/rails/arel.git'

2. bundle

3. bundle exec rails new . --dev --force

4. bundle exec rails s

Go to localhost:3000, you should now see 5.0.0.alpha in the environment.

Reference

Setting up Rails 5 app from edge

ActionController::UnknownHttpMethod:

In Rails 4.x:

In your tests, call process method like this:

 process :some_action, 'OPTIONS'

Redefining a Private Method in Ruby

class ActiveRecord

  private

  def hi
    'I am private'
  end
end

class ActiveRecord

  def greet
    hi
  end


  private

  def hi
    'I am redining you'
  end

end

a = ActiveRecord.new

p a.greet

Monkey patching (Coding Horror):

class ActiveRecord

  private

  def hi
    'I am private'
  end
end

class MyActiveRecord < ActiveRecord

  def greet
    hi
  end


  private

  def hi
    'I am redefining you'
  end

end

a = MyActiveRecord.new

p a.greet

Unnecessary Complication:

class Client

  def print
    say
  end

  private
 
  def say
    "hello"
  end
end

# Create a subclass of Client
MyClient = Class.new(Client) do
  define_method(:say) do
    "hello from an overridden private method"
  end
end

puts MyClient.superclass

my_client = MyClient.new
puts my_client.print

Simpler Way to Accomplish the Same Thing:

class Client

  def print
    say
  end

  private
 
  def say
    "hello"
  end
end

class MyClient < Client
  def say
    "hello from an overridden private method"
  end
end

puts MyClient.superclass

my_client = MyClient.new
puts my_client.print

Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true rails 4.2.4

In application.rb, inside the class add:

Rails.application.routes.default_url_options[:host] =  "load url that is appropriate for different environments in your app here"

Now you can go to the rails console:

 > include Rails.application.routes.url_helpers

and call different url_helpers like this:

profile_url

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

on Mac OS 10.10.5

Resolution: 

bundle update json

The scope body needs to be callable.

Change :

scope :world_has_not_ended, where('end_time >= ?', Time.now)

to

scope :world_has_not_ended, -> { where('end_time >= ?', Time.now) }

undefined method `pry' for #

Add:

require 'pry'

statement in spec_helper.rb