1 files changed, 119 insertions, 1 deletions
diff --git a/railties/lib/rails/test_unit/sub_test_task.rb b/railties/lib/rails/test_unit/sub_test_task.rb
index 87b6f9b5a4..6fa96d2ced 100644
--- a/railties/lib/rails/test_unit/sub_test_task.rb
+++ b/railties/lib/rails/test_unit/sub_test_task.rb
@@ -1,6 +1,124 @@
+require 'rake/testtask'
+
 module Rails
+  class TestTask < Rake::TestTask # :nodoc: all
+    # A utility class which is used primarily in "rails/test_unit/testing.rake"
+    # to help define rake tasks corresponding to <tt>rake test</tt>.
+    #
+    # This class takes a TestInfo class and defines the appropriate rake task
+    # based on the information, then invokes it.
+    class TestCreator # :nodoc:
+      def initialize(info)
+        @info = info
+      end
+
+      def invoke_rake_task
+        if @info.files.any?
+          create_and_run_single_test
+          reset_application_tasks
+        else
+          Rake::Task[ENV['TEST'] ? 'test:single' : 'test:run'].invoke
+        end
+      end
+
+      private
+
+        def create_and_run_single_test
+          Rails::TestTask.new('test:single') { |t|
+            t.test_files = @info.files
+          }
+          ENV['TESTOPTS'] ||= @info.opts
+          Rake::Task['test:single'].invoke
+        end
+
+        def reset_application_tasks
+          Rake.application.top_level_tasks.replace @info.tasks
+        end
+    end
+
+    # This is a utility class used by the <tt>TestTask::TestCreator</tt> class.
+    # This class takes a set of test tasks and checks to see if they correspond
+    # to test files (or can be transformed into test files). Calling <tt>files</tt>
+    # provides the set of test files and is used when initializing tests after
+    # a call to <tt>rake test</tt>.
+    class TestInfo # :nodoc:
+      def initialize(tasks)
+        @tasks = tasks
+        @files = nil
+      end
+
+      def files
+        @files ||= @tasks.map { |task|
+          [task, translate(task)].find { |file| test_file?(file) }
+        }.compact
+      end
+
+      def translate(file)
+        if file =~ /^app\/(.*)$/
+          "test/#{$1.sub(/\.rb$/, '')}_test.rb"
+        else
+          "test/#{file}_test.rb"
+        end
+      end
+
+      def tasks
+        @tasks - test_file_tasks - opt_names
+      end
+
+      def opts
+        opts = opt_names
+        if opts.any?
+          "-n #{opts.join ' '}"
+        end
+      end
+
+      private
+
+      def test_file_tasks
+        @tasks.find_all { |task|
+          [task, translate(task)].any? { |file| test_file?(file) }
+        }
+      end
+
+      def test_file?(file)
+        file =~ /^test/ && File.file?(file) && !File.directory?(file)
+      end
+
+      def opt_names
+        (@tasks - test_file_tasks).reject { |t| task_defined? t }
+      end
+
+      def task_defined?(task)
+        Rake::Task.task_defined? task
+      end
+    end
+
+    def self.test_creator(tasks)
+      info = TestInfo.new(tasks)
+      TestCreator.new(info)
+    end
+
+    def initialize(name = :test)
+      super
+      @libs << "test" # lib *and* test seem like a better default
+    end
+
+    def define
+      task @name do
+        if ENV['TESTOPTS']
+          ARGV.replace Shellwords.split ENV['TESTOPTS']
+        end
+        libs = @libs - $LOAD_PATH
+        $LOAD_PATH.unshift(*libs)
+        file_list.each { |fl|
+          FileList[fl].to_a.each { |f| require File.expand_path f }
+        }
+      end
+    end
+  end
+
   # Silence the default description to cut down on `rake -T` noise.
-  class SubTestTask < Rake::TestTask
+  class SubTestTask < Rake::TestTask # :nodoc:
     def desc(string)
       # Ignore the description.
     end