autotest.rb

# Watch for source changes
watch(/^.*cs$/i) do |m| rake end
# Watch for test output processing changes
watch(/^Rakefile$/i) do |m| rake 'myproject:test' end

def rake(task = 'myproject')
  system 'rake', task
end

Rakefile

require 'albacore'
require 'rexml/document'

# Will submit this as a patch when github starts letting me push again.
module Rake
  class MSBuildTask
    def define
      task name do
        fail unless @msbuild.build
      end
    end
  end
end

desc 'Build and test MyProject.Tests'
task 'myproject' => %W(myproject:build myproject:test)

namespace 'myproject' do
  Configuration = 'Debug'

  desc 'Build MyProject.Tests'
  Rake::MSBuildTask.new(:build) do |msb|
    msb.properties :configuration => Configuration, :platform => 'x86'
    msb.targets %W( MyProject_Tests )
    msb.solution = 'MySolution.sln'
  end

  desc 'Run MyProject.Tests'
  task :test do 
    rm 'results.trx' if File.exist? 'results.trx'
    mstest_cmd =%W(mstest
      /testcontainer:MyProject.Tests\\bin\\x86\\#{Configuration}\\MyProject.Tests.dll
      /runconfig:ContinuousBuild.testrunconfig
      /resultsfile:results.trx)
    sh(*mstest_cmd) do |ok, status|
      process('results.trx')
    end
  end

  def process(results_file)
    fail_count = 0
    File.open(results_file) do |file|
      xml =REXML::Document.new(file)
      xml.elements.each '//UnitTestResult[@outcome="Failed"]' do |e|
        puts ''
        puts '**********************************'
        puts e.attributes['testName']
        puts e.elements['Output/ErrorInfo/Message'].get_text.value
        puts e.elements['Output/ErrorInfo/StackTrace'].get_text.value
        puts ''
        fail_count = fail_count.succ
      end
    end
    fail "#{fail_count} tests failed" if fail_count > 0
  end
end