start in on migrations for styles

features/regenerating_styles.feature

@@ -0,0 +1,53 @@
+Feature: Regenerating styles
+
+  Scenario: Adding a new style
+    Given I generate a new rails application
+    And I have made a simple avatar on the user model
+    And I start the rails application
+    And I upload an avatar to the user model
+    When I add the following style to the user avatar:
+    """
+    large: '124x124#'
+    """
+    And I change the user show page to show the large avatar
+    Then I see a missing large avatar on the user show page
+    When I generate the "add_large_thumbnail_to_user_avatar" migration as follows:
+    """
+    def up
+      add_style :users, :avatar, large: '124x124#'
+    end
+
+    def down
+      remove_style :users, :avatar, :large
+    end
+    """
+    And I run the up database migration
+    Then I see the large avatar on the user show page
+    When I run the down database migration
+    Then I see a missing large avatar on the user show page
+
+  Scenario: Changing an existing style
+    Given I generate a new rails application
+    And I have made the following avatar style on the user model:
+    """
+    thumbnail: '32x32'
+    """
+    And I upload an avatar to the user model
+    When I change the avatar style on the user model to:
+    """
+    thumbnail: '16x16'
+    """
+    Then I see a "32x32" thumbnail avatar on the user show page
+    When I generate the "change_user_avatar_thumbnail_size" migration
+    And the "up" migration for "change_user_avatar_thumbnail_size" is:
+    """
+    change_style :users, :avatar, thumbnail: '16x16'
+    """
+    And the "down" migration for "change_user_avatar_thumbnail_size" is:
+    """
+    change_style :users, :avatar, thumbnail: '32x32'
+    """
+    And I run the up database migration
+    Then I see a "16x16" thumbnail avatar on the user show page
+    When I run the down database migration
+    Then I see a "32x32" thumbnail avatar on the user show page

features/step_definitions/mvc_steps.rb

@@ -0,0 +1,88 @@
+Given /^I have made a simple avatar on the user model$/ do
+  run_simple(%{bundle exec #{generator_command} scaffold user})
+  run_simple(%{bundle exec #{generator_command} paperclip user avatar})
+  run_simple(%{bundle exec rake db:migrate})
+  write_file('app/views/users/new.html.erb', <<-VIEW)
+    <%= form_for @user, :html => { :multipart => true } do |f| %>
+      <%= f.label :avatar %>
+      <%= f.file_field :avatar %>
+      <%= submit_tag 'Submit' %>
+    <% end %>
+  VIEW
+  write_file('app/views/users/show.html.erb', <<-VIEW)
+    <p>Attachment: <%= image_tag @user.avatar.url(:thumbnail) %></p>
+  VIEW
+  write_file('app/models/user.rb', <<-MODEL)
+    class User < ActiveRecord::Base
+      has_attached_file :avatar, styles: { thumbnail: '8x8#' }
+      attr_accessible :avatar
+    end
+  MODEL
+end
+
+Given /^I upload an avatar to the user model$/ do
+  visit '/users/new'
+  attach_file('Avatar', File.expand_path('test/fixtures/5k.png'))
+  click_button 'Submit'
+end
+
+When /^I add the following style to the user avatar:$/ do |string|
+  write_file('app/models/user.rb', <<-MODEL)
+    class User < ActiveRecord::Base
+      has_attached_file :avatar, styles: { thumbnail: '8x8#', #{string} }
+      attr_accessible :avatar
+    end
+  MODEL
+end
+
+When /^I change the user show page to show the large avatar$/ do
+  write_file('app/views/users/show.html.erb', <<-VIEW)
+    <p>Attachment: <%= image_tag @user.avatar.url(:large) %></p>
+  VIEW
+end
+
+Then /^I see a missing large avatar on the user show page$/ do
+  user = User.last
+  user.should_not be_nil
+  visit "/users/#{user.to_param}"
+
+  page.source =~ %r{img alt="5k" src="([^"]+)?.*"}
+  image_path = $1
+  image_path.should_not be_blank
+
+  File.should_not be_exist(Rails.root.join('public',image_path))
+end
+
+When /^I generate the "(.*?)" migration as follows:$/ do |migration_name, code|
+  run_simple(%{bundle exec ./script/rails generate migration #{migration_name}})
+  migration_filename = Dir[Rails.root.join('db', 'migrate', "*#{migration_name}.rb")].first
+  write_file(migration_filename, <<-MIGRATION)
+    class #{migration_name.classify} < ActiveRecord::Migration
+      #{code}
+    end
+  MIGRATION
+end
+
+When /^I run the up database migration$/ do
+  run_simple('bundle exec rake db:migrate')
+end
+
+When /^I run the down database migration$/ do
+  migration_filename = Dir[Rails.root.join('db', 'migrate', '*')].last
+  migration_filename =~ %r{.*/(\d+)_[^/]+.rb}
+  version = $1
+  version.should_not be_blank
+  run_simple("bundle exec rake db:migrate:down VERSION=#{version}")
+end
+
+Then /^I see the large avatar on the user show page$/ do
+  user = User.last
+  user.should_not be_nil
+  visit "/users/#{user.to_param}"
+
+  page.source =~ %r{img alt="5k" src="([^"]+)?.*"}
+  image_path = $1
+  image_path.should_not be_blank
+
+  File.should be_exist(Rails.root.join('public',image_path))
+end

test/schema_test.rb

@@ -64,7 +64,7 @@ def teardown
       Dummy.connection.create_table :dummies, :force => true
     end
 
-    context "migrating up" do
+    context '#add_attachment' do
       context "with single attachment" do
         setup do
           Dummy.connection.add_attachment :dummies, :avatar
@@ -111,7 +111,7 @@ def teardown
       end
     end
 
-    context "migrating down" do
+    context "#remove_attachment" do
       setup do
         Dummy.connection.change_table :dummies do |t|
           t.column :avatar_file_name, :string
@@ -196,5 +196,19 @@ def teardown
         end
       end
     end
+
+    context '#add_style' do
+      should 'process the specific style'
+
+      should 'raise if the style is missing' do
+        assert_raise ArgumentError do
+          Dummy.connection.add_style :dummies, :avatar, missing_style: '24x24'
+        end
+      end
+
+      should 'raise if the attachment is missing'
+
+      should 'raise if the model is missing'
+    end
   end
 end