Add 'foo:install:migrations' task to copy migrations from foo engine

railties/lib/rails/engine.rb

@@ -522,6 +522,20 @@ def load_seed
       # consistently executed after all the initializers above across all engines.
     end
 
+    rake_tasks do
+      next if self.is_a?(Rails::Application)
+
+      namespace railtie_name do
+        namespace :install do
+          desc "Copy migrations from #{railtie_name} to application"
+          task :migrations do
+            ENV["FROM"] = railtie_name
+            Rake::Task["railties:install:migrations"].invoke
+          end
+        end
+      end
+    end
+
   protected
     def routes?
       defined?(@routes)

railties/test/railties/shared_tests.rb

@@ -43,7 +43,7 @@ class CreateYaffles < ActiveRecord::Migration
       add_to_config "ActiveRecord::Base.timestamped_migrations = false"
 
       Dir.chdir(app_path) do
-        output = `rake railties:install:migrations FROM=bukkits 2>&1`
+        output = `rake bukkits:install:migrations 2>&1`
 
         assert File.exists?("#{app_path}/db/migrate/2_create_users.rb")
         assert File.exists?("#{app_path}/db/migrate/3_add_last_name_to_users.rb")