Allow rake to run ActiveRecord test case(s).

Author: metaskills

Rakefile

@@ -2,7 +2,15 @@ require 'rake/testtask'
 require_relative 'test/support/paths_sqlserver'
 
 def test_files
-  return ENV['TEST_FILES'].split(',') if ENV['TEST_FILES']
+  if files = ENV['AR_TEST_FILES']
+    files = files.split(',').map do |file|
+      File.join ARTest::SQLServer.root_activerecord, file.strip
+    end
+    return files.unshift 'test/cases/helper_sqlserver.rb'
+  end
+  if files = ENV['TEST_FILES']
+    return files.split(',').map(&:strip)
+  end
   sqlserver_cases = Dir.glob('test/cases/**/*_test_sqlserver.rb')
   ar_cases = Dir.glob("#{ARTest::SQLServer.root_activerecord}/test/cases/**/*_test.rb")
   if ENV['SQLSERVER_ONLY']