Merge branch 'master' into set_binds

* master: (2794 commits)
  doc, API example on how to use `Model#exists?` with multiple IDs. [ci skip]
  Restore DATABASE_URL even if it's nil in connection_handler test
  [ci skip] - error_messages_for has been deprecated since 2.3.8 - lets reduce any confusion for users
  Ensure Active Record connection consistency
  Revert "ask the fixture set for the sql statements"
  Check `respond_to` before delegation due to: https://github.com/ruby/ruby/commit/d781caaf313b8649948c107bba277e5ad7307314
  Adding Hash#compact and Hash#compact! methods
  MySQL version 4.1 was EOL on December 31, 2009 We should at least recommend modern versions of MySQL to users.
  clear cache on body close so that cache remains during rendering
  add a more restricted codepath for templates fixes #13390
  refactor generator tests to use block form of Tempfile
  Fix typo [ci skip]
  Move finish_template as the last public method in the generator
  Minor typos fix [ci skip]
  make `change_column_null` reversible. Closes #13576.
  create/drop test and development databases only if RAILS_ENV is nil
  Revert "Speedup String#to"
  typo fix in test name. [ci skip].
  `core_ext/string/access.rb` test what we are documenting.
  Fix typo in image_tag documentation
  ...

Conflicts:
	activerecord/lib/active_record/associations/join_dependency/join_association.rb
	activerecord/lib/active_record/relation/query_methods.rb

4 files changed, 19 insertions, 6 deletions

diff --git a/guides/code/getting_started/app/controllers/comments_controller.rb b/guides/code/getting_started/app/controllers/comments_controller.rb
index 0e3d2a6dde..b2d9bcdf7f 100644
--- a/guides/code/getting_started/app/controllers/comments_controller.rb
+++ b/guides/code/getting_started/app/controllers/comments_controller.rb
@@ -4,7 +4,7 @@ class CommentsController < ApplicationController
 
   def create
     @post = Post.find(params[:post_id])
-    @comment = @post.comments.create(params[:comment].permit(:commenter, :body))
+    @comment = @post.comments.create(comment_params)
     redirect_to post_path(@post)
   end
 
@@ -14,4 +14,10 @@ class CommentsController < ApplicationController
     @comment.destroy
     redirect_to post_path(@post)
   end
+
+  private
+
+    def comment_params
+      params.require(:comment).permit(:commenter, :body)
+    end
 end
diff --git a/guides/code/getting_started/app/controllers/posts_controller.rb b/guides/code/getting_started/app/controllers/posts_controller.rb
index 6aa1409170..02689ad67b 100644
--- a/guides/code/getting_started/app/controllers/posts_controller.rb
+++ b/guides/code/getting_started/app/controllers/posts_controller.rb
@@ -17,7 +17,7 @@ class PostsController < ApplicationController
   def update
     @post = Post.find(params[:id])
 
-    if @post.update(params[:post].permit(:title, :text))
+    if @post.update(post_params)
       redirect_to action: :show, id: @post.id
     else
       render 'edit'
@@ -29,7 +29,7 @@ class PostsController < ApplicationController
   end
 
   def create
-    @post = Post.new(params[:post].permit(:title, :text))
+    @post = Post.new(post_params)
 
     if @post.save
       redirect_to action: :show, id: @post.id
@@ -44,4 +44,10 @@ class PostsController < ApplicationController
 
     redirect_to action: :index
   end
+
+  private
+
+    def post_params
+      params.require(:post).permit(:title, :text)
+    end
 end
diff --git a/guides/code/getting_started/app/views/posts/_form.html.erb b/guides/code/getting_started/app/views/posts/_form.html.erb
index c9fb74af9c..f2f83585e1 100644
--- a/guides/code/getting_started/app/views/posts/_form.html.erb
+++ b/guides/code/getting_started/app/views/posts/_form.html.erb
@@ -1,6 +1,6 @@
 <%= form_for @post do |f| %>
   <% if @post.errors.any? %>
-  <div id="errorExplanation">
+  <div id="error_explanation">
     <h2><%= pluralize(@post.errors.count, "error") %> prohibited
       this post from being saved:</h2>
     <ul>
@@ -14,12 +14,12 @@
     <%= f.label :title %><br>
     <%= f.text_field :title %>
   </p>
- 
+
   <p>
     <%= f.label :text %><br>
     <%= f.text_area :text %>
   </p>
- 
+
   <p>
     <%= f.submit %>
   </p>
diff --git a/guides/code/getting_started/app/views/welcome/index.html.erb b/guides/code/getting_started/app/views/welcome/index.html.erb
index 738e12d7dc..56be8dd3cc 100644
--- a/guides/code/getting_started/app/views/welcome/index.html.erb
+++ b/guides/code/getting_started/app/views/welcome/index.html.erb
@@ -1,3 +1,4 @@
 <h1>Hello, Rails!</h1>
 
 <%= link_to "My Blog", controller: "posts" %>
+<%= link_to "New Post", new_post_path %>