rake railties:install:migrations respects the order of railties

This PR fixes #8930 and some stuff from #8985

2 files changed, 41 insertions, 0 deletions

diff --git a/railties/lib/rails/application.rb b/railties/lib/rails/application.rb
index 2fde974732..362713eb75 100644
--- a/railties/lib/rails/application.rb
+++ b/railties/lib/rails/application.rb
@@ -364,6 +364,10 @@ module Rails
       end
     end
 
+    def migration_railties # :nodoc:
+      (ordered_railties & railties_without_main_app).reverse
+    end
+
   protected
 
     alias :build_middleware_stack :app
@@ -394,6 +398,11 @@ module Rails
       super
     end
 
+    def railties_without_main_app # :nodoc:
+      @railties_without_main_app ||= Rails::Railtie.subclasses.map(&:instance) +
+        Rails::Engine.subclasses.map(&:instance)
+    end
+
     # Returns the ordered railties for this application considering railties_order.
     def ordered_railties #:nodoc:
       @ordered_railties ||= begin
diff --git a/railties/test/railties/engine_test.rb b/railties/test/railties/engine_test.rb
index 6240dc04ec..ec64ce5941 100644
--- a/railties/test/railties/engine_test.rb
+++ b/railties/test/railties/engine_test.rb
@@ -112,6 +112,38 @@ module RailtiesTest
       end
     end
 
+    test 'respects the order of railties when installing migrations' do
+      @blog = engine "blog" do |plugin|
+        plugin.write "lib/blog.rb", <<-RUBY
+          module Blog
+            class Engine < ::Rails::Engine
+            end
+          end
+        RUBY
+      end
+
+      @plugin.write "db/migrate/1_create_users.rb", <<-RUBY
+        class CreateUsers < ActiveRecord::Migration
+        end
+      RUBY
+
+      @blog.write "db/migrate/2_create_blogs.rb", <<-RUBY
+        class CreateBlogs < ActiveRecord::Migration
+        end
+      RUBY
+
+      add_to_config("config.railties_order = [Bukkits::Engine, Blog::Engine, :all, :main_app]")
+
+      boot_rails
+
+      Dir.chdir(app_path) do
+        output  = `bundle exec rake railties:install:migrations`.split("\n")
+
+        assert_match(/Copied migration \d+_create_users.bukkits.rb from bukkits/, output.first)
+        assert_match(/Copied migration \d+_create_blogs.blog_engine.rb from blog_engine/, output.last)
+      end
+    end
+
     test "mountable engine should copy migrations within engine_path" do
       @plugin.write "lib/bukkits.rb", <<-RUBY
         module Bukkits