Guardfile

guard :bundler do
  watch('Gemfile')
end

guard :minitest, spring: true, env: {GUARD: 'true'}, all_env: :GUARD_COVERAGE, all_after_pass: false, all_on_start: false do
  # with Minitest::Unit
  watch(%r{^test/(.*)\/?test_(.*)\.rb$})
  watch(%r{^lib/(.*/)?([^/]+)\.rb$})     { |m| "test/#{m[1]}test_#{m[2]}.rb" }
  watch(%r{^test/test_helper\.rb$})      { 'test' }

  # Rails 4
  watch(%r{^app/(.+)\.rb})                                { |m| "test/#{m[1]}_test.rb" }
  watch(%r{^app/controllers/application_controller\.rb$}) { 'test/controllers' }
  watch(%r{^app/controllers/(.+)_controller\.rb$})        { |m| "test/integration/#{m[1]}_test.rb" }
  watch(%r{^app/jobs/(.+)\.rb$})                          { |m| "test/jobs/#{m[1]}_test.rb" }
  watch(%r{^lib/(.+)\.rb$})                               { |m| "test/lib/#{m[1]}_test.rb" }
  watch(%r{^test/.+_test\.rb$})
  watch(%r{^test/test_helper\.rb$})                       { 'test' }
  watch(%r{^test/factories/(.+)_factory\.rb$})            { |m| "test/models/#{m[1]}_test.rb" }
end