15 files changed, 84 insertions, 50 deletions

diff --git a/guides/source/3_0_release_notes.md b/guides/source/3_0_release_notes.md
index d398cd680c..cf9d694de7 100644
--- a/guides/source/3_0_release_notes.md
+++ b/guides/source/3_0_release_notes.md
@@ -73,8 +73,6 @@ You can see an example of how that works at [Rails Upgrade is now an Official Pl
 
 Aside from Rails Upgrade tool, if you need more help, there are people on IRC and [rubyonrails-talk](http://groups.google.com/group/rubyonrails-talk) that are probably doing the same thing, possibly hitting the same issues. Be sure to blog your own experiences when upgrading so others can benefit from your knowledge!
 
-More information - [The Path to Rails 3: Approaching the upgrade](http://omgbloglol.com/post/353978923/the-path-to-rails-3-approaching-the-upgrade)
-
 Creating a Rails 3.0 application
 --------------------------------
 
diff --git a/guides/source/active_model_basics.md b/guides/source/active_model_basics.md
index 1d87646e49..0019d08328 100644
--- a/guides/source/active_model_basics.md
+++ b/guides/source/active_model_basics.md
@@ -120,8 +120,8 @@ class Person
   end
 
   def save
-    @previously_changed = changes
     # do save work...
+    changes_applied
   end
 end
 ```
diff --git a/guides/source/active_record_basics.md b/guides/source/active_record_basics.md
index ad08cb01f7..34baae509b 100644
--- a/guides/source/active_record_basics.md
+++ b/guides/source/active_record_basics.md
@@ -48,10 +48,10 @@ overall database access code.
 Active Record gives us several mechanisms, the most important being the ability
 to:
 
-* Represent models and their data
-* Represent associations between these models
-* Represent inheritance hierarchies through related models
-* Validate models before they get persisted to the database
+* Represent models and their data.
+* Represent associations between these models.
+* Represent inheritance hierarchies through related models.
+* Validate models before they get persisted to the database.
 * Perform database operations in an object-oriented fashion.
 
 Convention over Configuration in Active Record
@@ -78,9 +78,9 @@ of two or more words, the model class name should follow the Ruby conventions,
 using the CamelCase form, while the table name must contain the words separated
 by underscores. Examples:
 
-* Database Table - Plural with underscores separating words (e.g., `book_clubs`)
+* Database Table - Plural with underscores separating words (e.g., `book_clubs`).
 * Model Class - Singular with the first letter of each word capitalized (e.g.,
-`BookClub`)
+`BookClub`).
 
 | Model / Class | Table / Schema |
 | ------------- | -------------- |
@@ -101,7 +101,7 @@ depending on the purpose of these columns.
   fields that Active Record will look for when you create associations between
   your models.
 * **Primary keys** - By default, Active Record will use an integer column named
-  `id` as the table's primary key. When using [Rails
+  `id` as the table's primary key. When using [Active Record
   Migrations](migrations.html) to create your tables, this column will be
   automatically created.
 
@@ -116,7 +116,7 @@ to Active Record instances:
   locking](http://api.rubyonrails.org/classes/ActiveRecord/Locking.html) to
   a model.
 * `type` - Specifies that the model uses [Single Table
-  Inheritance](http://api.rubyonrails.org/classes/ActiveRecord/Base.html)
+  Inheritance](http://api.rubyonrails.org/classes/ActiveRecord/Base.html).
 * `(association_name)_type` - Stores the type for
   [polymorphic associations](association_basics.html#polymorphic-associations).
 * `(table_name)_count` - Used to cache the number of belonging objects on
@@ -368,6 +368,6 @@ Rails keeps track of which files have been committed to the database and
 provides rollback features. To actually create the table, you'd run `rake db:migrate`
 and to roll it back, `rake db:rollback`.
 
-Note that the above code is database-agnostic: it will run in MySQL, postgresql,
-Oracle and others. You can learn more about migrations in the [Active Record
-Migrations guide](migrations.html)
+Note that the above code is database-agnostic: it will run in MySQL,
+PostgreSQL, Oracle and others. You can learn more about migrations in the
+[Active Record Migrations guide](migrations.html).
diff --git a/guides/source/active_record_querying.md b/guides/source/active_record_querying.md
index 28013beeae..faa37efd37 100644
--- a/guides/source/active_record_querying.md
+++ b/guides/source/active_record_querying.md
@@ -1358,7 +1358,7 @@ COMMIT
 
 The new record might not be saved to the database; that depends on whether validations passed or not (just like `create`).
 
-Suppose we want to set the 'locked' attribute to true if we're
+Suppose we want to set the 'locked' attribute to `false` if we're
 creating a new record, but we don't want to include it in the query. So
 we want to find the client named "Andy", or if that client doesn't
 exist, create a client named "Andy" which is not locked.
diff --git a/guides/source/association_basics.md b/guides/source/association_basics.md
index c58dd2e90a..91b268d766 100644
--- a/guides/source/association_basics.md
+++ b/guides/source/association_basics.md
@@ -261,7 +261,10 @@ With `through: :sections` specified, Rails will now understand:
 
 ### The `has_one :through` Association
 
-A `has_one :through` association sets up a one-to-one connection with another model. This association indicates that the declaring model can be matched with one instance of another model by proceeding _through_ a third model. For example, if each supplier has one account, and each account is associated with one account history, then the customer model could look like this:
+A `has_one :through` association sets up a one-to-one connection with another model. This association indicates
+that the declaring model can be matched with one instance of another model by proceeding _through_ a third model.
+For example, if each supplier has one account, and each account is associated with one account history, then the
+supplier model could look like this:
 
 ```ruby
 class Supplier < ActiveRecord::Base
@@ -337,7 +340,7 @@ class CreateAssembliesAndParts < ActiveRecord::Migration
       t.timestamps
     end
 
-    create_table :assemblies_parts do |t|
+    create_table :assemblies_parts, id: false do |t|
       t.belongs_to :assembly
       t.belongs_to :part
     end
diff --git a/guides/source/command_line.md b/guides/source/command_line.md
index 6f792be8ae..ef645c3d2d 100644
--- a/guides/source/command_line.md
+++ b/guides/source/command_line.md
@@ -1,8 +1,6 @@
 The Rails Command Line
 ======================
 
-Rails comes with every command line tool you'll need to
-
 After reading this guide, you will know:
 
 * How to create a Rails application.
diff --git a/guides/source/configuring.md b/guides/source/configuring.md
index 5f170474ee..c499cd0727 100644
--- a/guides/source/configuring.md
+++ b/guides/source/configuring.md
@@ -759,4 +759,15 @@ Since the connection pooling is handled inside of Active Record by default, all
 
 Any one request will check out a connection the first time it requires access to the database, after which it will check the connection back in, at the end of the request, meaning that the additional connection slot will be available again for the next request in the queue.
 
+If you try to use more connections than are available, Active Record will block
+and wait for a connection from the pool. When it cannot get connection, a timeout
+error similar to given below will be thrown.
+
+```ruby
+ActiveRecord::ConnectionTimeoutError - could not obtain a database connection within 5 seconds. The max pool size is currently 5; consider increasing it:
+```
+
+If you get the above error, you might want to increase the size of connection 
+pool by incrementing the `pool` option in `database.yml`
+
 NOTE. If you have enabled `Rails.threadsafe!` mode then there could be a chance that several threads may be accessing multiple connections simultaneously. So depending on your current request load, you could very well have multiple threads contending for a limited amount of connections.
diff --git a/guides/source/engines.md b/guides/source/engines.md
index ec51fb9234..c71b728ef7 100644
--- a/guides/source/engines.md
+++ b/guides/source/engines.md
@@ -307,7 +307,11 @@ create      test/models/blorgh/comment_test.rb
 create      test/fixtures/blorgh/comments.yml
 ```
 
-This generator call will generate just the necessary model files it needs, namespacing the files under a `blorgh` directory and creating a model class called `Blorgh::Comment`.
+This generator call will generate just the necessary model files it needs, namespacing the files under a `blorgh` directory and creating a model class called `Blorgh::Comment`. Now run the migration to create our blorgh_comments table:
+
+```bash
+$ rake db:migrate
+```
 
 To show the comments on a post, edit `app/views/blorgh/posts/show.html.erb` and add this line before the "Edit" link:
 
@@ -950,7 +954,7 @@ INFO. Remember that in order to use languages like Sass or CoffeeScript, you sho
 
 There are some situations where your engine's assets are not required by the host application. For example, say that you've created
 an admin functionality that only exists for your engine. In this case, the host application doesn't need to require `admin.css`
-or `admin.js`. Only the gem's admin layout needs these assets. It doesn't make sense for the host app to include `"blorg/admin.css"` in it's stylesheets. In this situation, you should explicitly define these assets for precompilation.
+or `admin.js`. Only the gem's admin layout needs these assets. It doesn't make sense for the host app to include `"blorgh/admin.css"` in it's stylesheets. In this situation, you should explicitly define these assets for precompilation.
 This tells sprockets to add your engine assets when `rake assets:precompile` is ran.
 
 You can define assets for precompilation in `engine.rb`
diff --git a/guides/source/form_helpers.md b/guides/source/form_helpers.md
index 0287b3df73..4b6d8a93f0 100644
--- a/guides/source/form_helpers.md
+++ b/guides/source/form_helpers.md
@@ -973,4 +973,4 @@ As a convenience you can instead pass the symbol `:all_blank` which will create
 
 ### Adding Fields on the Fly
 
-Rather than rendering multiple sets of fields ahead of time you may wish to add them only when a user clicks on an 'Add new child' button. Rails does not provide any builtin support for this. When generating new sets of fields you must ensure the key of the associated array is unique - the current javascript date (milliseconds after the epoch) is a common choice.
+Rather than rendering multiple sets of fields ahead of time you may wish to add them only when a user clicks on an 'Add new address' button. Rails does not provide any builtin support for this. When generating new sets of fields you must ensure the key of the associated array is unique - the current JavaScript date (milliseconds after the epoch) is a common choice.
diff --git a/guides/source/generators.md b/guides/source/generators.md
index a8a34d0ac4..e06b13deba 100644
--- a/guides/source/generators.md
+++ b/guides/source/generators.md
@@ -35,7 +35,7 @@ $ rails generate helper --help
 Creating Your First Generator
 -----------------------------
 
-Since Rails 3.0, generators are built on top of [Thor](https://github.com/wycats/thor). Thor provides powerful options parsing and a great API for manipulating files. For instance, let's build a generator that creates an initializer file named `initializer.rb` inside `config/initializers`.
+Since Rails 3.0, generators are built on top of [Thor](https://github.com/erikhuda/thor). Thor provides powerful options parsing and a great API for manipulating files. For instance, let's build a generator that creates an initializer file named `initializer.rb` inside `config/initializers`.
 
 The first step is to create a file at `lib/generators/initializer_generator.rb` with the following content:
 
@@ -47,7 +47,7 @@ class InitializerGenerator < Rails::Generators::Base
 end
 ```
 
-NOTE: `create_file` is a method provided by `Thor::Actions`. Documentation for `create_file` and other Thor methods can be found in [Thor's documentation](http://rdoc.info/github/wycats/thor/master/Thor/Actions.html)
+NOTE: `create_file` is a method provided by `Thor::Actions`. Documentation for `create_file` and other Thor methods can be found in [Thor's documentation](http://rdoc.info/github/erikhuda/thor/master/Thor/Actions.html)
 
 Our new generator is quite simple: it inherits from `Rails::Generators::Base` and has one method definition. When a generator is invoked, each public method in the generator is executed sequentially in the order that it is defined. Finally, we invoke the `create_file` method that will create a file at the given destination with the given content. If you are familiar with the Rails Application Templates API, you'll feel right at home with the new generators API.
 
@@ -171,7 +171,7 @@ Before we customize our workflow, let's first see what our scaffold looks like:
 ```bash
 $ rails generate scaffold User name:string
       invoke  active_record
-      create    db/migrate/20091120125558_create_users.rb
+      create    db/migrate/20130924151154_create_users.rb
       create    app/models/user.rb
       invoke    test_unit
       create      test/models/user_test.rb
@@ -193,6 +193,9 @@ $ rails generate scaffold User name:string
       create      app/helpers/users_helper.rb
       invoke      test_unit
       create        test/helpers/users_helper_test.rb
+      invoke    jbuilder
+      create      app/views/users/index.json.jbuilder
+      create      app/views/users/show.json.jbuilder
       invoke  assets
       invoke    coffee
       create      app/assets/javascripts/users.js.coffee
@@ -221,11 +224,18 @@ To demonstrate this, we are going to create a new helper generator that simply a
 
 ```bash
 $ rails generate generator rails/my_helper
+      create  lib/generators/rails/my_helper
+      create  lib/generators/rails/my_helper/my_helper_generator.rb
+      create  lib/generators/rails/my_helper/USAGE
+      create  lib/generators/rails/my_helper/templates
 ```
 
-After that, we can delete both the `templates` directory and the `source_root` class method from our new generators, because we are not going to need them. So our new generator looks like the following:
+After that, we can delete both the `templates` directory and the `source_root`
+class method call from our new generator, because we are not going to need them.
+Add the method below, so our generator looks like the following:
 
 ```ruby
+# lib/generators/rails/my_helper/my_helper_generator.rb
 class Rails::MyHelperGenerator < Rails::Generators::NamedBase
   def create_helper_file
     create_file "app/helpers/#{file_name}_helper.rb", <<-FILE
@@ -241,6 +251,7 @@ We can try out our new generator by creating a helper for users:
 
 ```bash
 $ rails generate my_helper products
+      create  app/helpers/products_helper.rb
 ```
 
 And it will generate the following helper file in `app/helpers`:
@@ -279,6 +290,7 @@ Since Rails 3.0, this is easy to do due to the hooks concept. Our new helper doe
 To do that, we can change the generator this way:
 
 ```ruby
+# lib/generators/rails/my_helper/my_helper_generator.rb
 class Rails::MyHelperGenerator < Rails::Generators::NamedBase
   def create_helper_file
     create_file "app/helpers/#{file_name}_helper.rb", <<-FILE
@@ -351,7 +363,7 @@ Now, if you create a Comment scaffold, you will see that the shoulda generators
 ```bash
 $ rails generate scaffold Comment body:text
       invoke  active_record
-      create    db/migrate/20091120151323_create_comments.rb
+      create    db/migrate/20130924143118_create_comments.rb
       create    app/models/comment.rb
       invoke    shoulda
       create      test/models/comment_test.rb
@@ -373,6 +385,9 @@ $ rails generate scaffold Comment body:text
       create      app/helpers/comments_helper.rb
       invoke      shoulda
       create        test/helpers/comments_helper_test.rb
+      invoke    jbuilder
+      create      app/views/comments/index.json.jbuilder
+      create      app/views/comments/show.json.jbuilder
       invoke  assets
       invoke    coffee
       create      app/assets/javascripts/comments.js.coffee
@@ -422,7 +437,7 @@ Generator methods
 
 The following are methods available for both generators and templates for Rails.
 
-NOTE: Methods provided by Thor are not covered this guide and can be found in [Thor's documentation](http://rdoc.info/github/wycats/thor/master/Thor/Actions.html)
+NOTE: Methods provided by Thor are not covered this guide and can be found in [Thor's documentation](http://rdoc.info/github/erikhuda/thor/master/Thor/Actions.html)
 
 ### `gem`
 
diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md
index e5bc5ef038..400615878b 100644
--- a/guides/source/getting_started.md
+++ b/guides/source/getting_started.md
@@ -22,8 +22,8 @@ with Rails. However, to get the most out of it, you need to have some
 prerequisites installed:
 
 * The [Ruby](http://www.ruby-lang.org/en/downloads) language version 1.9.3 or newer
-* The [RubyGems](http://rubygems.org/) packaging system
-    * To learn more about RubyGems, please read the [RubyGems User Guide](http://docs.rubygems.org/read/book/1)
+* The [RubyGems](http://rubygems.org) packaging system
+    * To learn more about RubyGems, please read the [RubyGems Guides](http://guides.rubygems.org)
 * A working installation of the [SQLite3 Database](http://www.sqlite.org)
 
 Rails is a web application framework running on the Ruby programming language.
@@ -262,7 +262,7 @@ of code:
 ### Setting the Application Home Page
 
 Now that we have made the controller and view, we need to tell Rails when we
-want Hello Rails! to show up. In our case, we want it to show up when we
+want `Hello, Rails!` to show up. In our case, we want it to show up when we
 navigate to the root URL of our site, <http://localhost:3000>. At the moment,
 "Welcome Aboard" is occupying that spot.
 
@@ -687,7 +687,7 @@ invoking the command: `rake db:migrate RAILS_ENV=production`.
 
 ### Saving data in the controller
 
-Back in `posts_controller`, we need to change the `create` action
+Back in `PostsController`, we need to change the `create` action
 to use the new `Post` model to save the data in the database. Open `app/controllers/posts_controller.rb`
 and change the `create` action to look like this:
 
@@ -846,7 +846,7 @@ Open `app/views/welcome/index.html.erb` and modify it as follows:
 
 ```html+erb
 <h1>Hello, Rails!</h1>
-<%= link_to "My Blog", controller: "posts" %>
+<%= link_to 'My Blog', controller: 'posts' %>
 ```
 
 The `link_to` method is one of Rails' built-in view helpers. It creates a
@@ -1013,7 +1013,7 @@ errors with `@post.errors.full_messages`.
 arguments. If the number is greater than one, the string will be automatically
 pluralized.
 
-The reason why we added `@post = Post.new` in `posts_controller` is that
+The reason why we added `@post = Post.new` in the `PostsController` is that
 otherwise `@post` would be `nil` in our view, and calling
 `@post.errors.any?` would throw an error.
 
@@ -1031,7 +1031,7 @@ attempt to do just that on the new post form [(http://localhost:3000/posts/new)]
 We've covered the "CR" part of CRUD. Now let's focus on the "U" part, updating
 posts.
 
-The first step we'll take is adding an `edit` action to `posts_controller`.
+The first step we'll take is adding an `edit` action to the `PostsController`.
 
 ```ruby
 def edit
@@ -1338,7 +1338,7 @@ class Comment < ActiveRecord::Base
 end
 ```
 
-This is very similar to the `post.rb` model that you saw earlier. The difference
+This is very similar to the `Post` model that you saw earlier. The difference
 is the line `belongs_to :post`, which sets up an Active Record _association_.
 You'll learn a little about associations in the next section of this guide.
 
@@ -1816,6 +1816,7 @@ class CommentsController < ApplicationController
     @post = Post.find(params[:post_id])
     ...
   end
+
   # snipped for brevity
 ```
 
diff --git a/guides/source/i18n.md b/guides/source/i18n.md
index 948b6f167c..33daa79133 100644
--- a/guides/source/i18n.md
+++ b/guides/source/i18n.md
@@ -843,6 +843,7 @@ So, for example, instead of the default error message `"can not be blank"` you c
 | numericality | :equal_to                 | :equal_to                 | count         |
 | numericality | :less_than                | :less_than                | count         |
 | numericality | :less_than_or_equal_to    | :less_than_or_equal_to    | count         |
+| numericality | :only_integer             | :not_an_integer           | -             |
 | numericality | :odd                      | :odd                      | -             |
 | numericality | :even                     | :even                     | -             |
 
diff --git a/guides/source/migrations.md b/guides/source/migrations.md
index ab39b39a1c..0f5379059e 100644
--- a/guides/source/migrations.md
+++ b/guides/source/migrations.md
@@ -301,6 +301,7 @@ braces. You can use the following modifiers:
 * `precision`    Defines the precision for the `decimal` fields
 * `scale`        Defines the scale for the `decimal` fields
 * `polymorphic`  Adds a `type` column for `belongs_to` associations
+* `null`         Allows or disallows `NULL` values in the column.
 
 For instance, running
 
@@ -313,7 +314,7 @@ will produce a migration that looks like this
 ```ruby
 class AddDetailsToProducts < ActiveRecord::Migration
   def change
-    add_column :products, :price, precision: 5, scale: 2
+    add_column :products, :price, :decimal, precision: 5, scale: 2
     add_reference :products, :supplier, polymorphic: true, index: true
   end
 end
@@ -703,9 +704,9 @@ The `rake db:reset` task will drop the database and set it up again. This is
 functionally equivalent to `rake db:drop db:setup`.
 
 NOTE: This is not the same as running all the migrations. It will only use the
-contents of the current schema.rb file. If a migration can't be rolled back,
-'rake db:reset' may not help you. To find out more about dumping the schema see
-'[schema dumping and you](#schema-dumping-and-you).'
+contents of the current `schema.rb` file. If a migration can't be rolled back,
+`rake db:reset` may not help you. To find out more about dumping the schema see
+[Schema Dumping and You](#schema-dumping-and-you) section.
 
 ### Running Specific Migrations
 
diff --git a/guides/source/plugins.md b/guides/source/plugins.md
index b52504b104..ca55ee0df2 100644
--- a/guides/source/plugins.md
+++ b/guides/source/plugins.md
@@ -15,7 +15,7 @@ After reading this guide, you will know:
 This guide describes how to build a test-driven plugin that will:
 
 * Extend core Ruby classes like Hash and String.
-* Add methods to ActiveRecord::Base in the tradition of the 'acts_as' plugins.
+* Add methods to `ActiveRecord::Base` in the tradition of the `acts_as` plugins.
 * Give you information about where to put generators in your plugin.
 
 For the purpose of this guide pretend for a moment that you are an avid bird watcher.
@@ -126,8 +126,8 @@ $ rails console
 Add an "acts_as" Method to Active Record
 ----------------------------------------
 
-A common pattern in plugins is to add a method called 'acts_as_something' to models. In this case, you
-want to write a method called 'acts_as_yaffle' that adds a 'squawk' method to your Active Record models.
+A common pattern in plugins is to add a method called `acts_as_something` to models. In this case, you
+want to write a method called `acts_as_yaffle` that adds a `squawk` method to your Active Record models.
 
 To begin, set up your files so that you have:
 
@@ -162,9 +162,9 @@ end
 
 ### Add a Class Method
 
-This plugin will expect that you've added a method to your model named 'last_squawk'. However, the
-plugin users might have already defined a method on their model named 'last_squawk' that they use
-for something else. This plugin will allow the name to be changed by adding a class method called 'yaffle_text_field'.
+This plugin will expect that you've added a method to your model named `last_squawk`. However, the
+plugin users might have already defined a method on their model named `last_squawk` that they use
+for something else. This plugin will allow the name to be changed by adding a class method called `yaffle_text_field`.
 
 To start out, write a failing test that shows the behavior you'd like:
 
diff --git a/guides/source/testing.md b/guides/source/testing.md
index 5b8829b89a..50115607c9 100644
--- a/guides/source/testing.md
+++ b/guides/source/testing.md
@@ -438,10 +438,12 @@ Now that we have used Rails scaffold generator for our `Post` resource, it has a
 Let me take you through one such test, `test_should_get_index` from the file `posts_controller_test.rb`.
 
 ```ruby
-test "should get index" do
-  get :index
-  assert_response :success
-  assert_not_nil assigns(:posts)
+class PostsControllerTest < ActionController::TestCase
+  test "should get index" do
+    get :index
+    assert_response :success
+    assert_not_nil assigns(:posts)
+  end
 end
 ```