在 `rake test` 之后执行 rake 任务

Executing a rake task after `rake test`

我正在尝试为 Rails 4.0.2 (Ruby 2.2.3) 项目创建一个 rake 任务,该项目创建测试数据库和播种,然后运行测试套件,最后通过删除测试数据库进行清理。下面是一个简单的例子:

task better_test: :environment do
  Rake::Task["test:setup"].execute
  Rake::Task["test"].execute
  Rake::Task["test:cleanup"].execute
end

上面的任务确实调用了 test:setup rake 任务(create/seed 测试数据库),然后调用了 test rake 任务,最后调用了 test:cleanup rake任务。然而,问题是最后一个 test:cleanuptest rake 任务完成 运行 之前被调用。在前面的任务完成后,是否仍然可以调用清理 rake 任务?

这是 运行 跟踪任务的输出:

$ RAILS_ENV=test be rake better_test --trace
/usr/local/rvm/gems/ruby-2.2.3/gems/activesupport-4.0.2/lib/active_support/values/time_zone.rb:282: warning: circular argument reference - now
/usr/local/rvm/gems/ruby-2.2.3/gems/honeybadger-1.16.3/lib/honeybadger/rack/user_feedback.rb:51: warning: circular argument reference - action
** Invoke better_test (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute better_test
** Execute test:setup
Creating test database.
** Execute db:test:setup
** Execute db:test:create
** Execute db:create
** Execute db:test:load
** Execute db:schema:load
** Execute db:test_project:setup
** Execute db:test_project:create
** Invoke db:create (first_time)
** Invoke environment
** Execute db:create
** Execute db:test_project:migrate:down
** Execute db:test_project:migrate:up
** Execute db:test_project:seed
** Execute test
** Invoke test:run (first_time)
** Invoke test:units (first_time)
** Invoke test:prepare (first_time)
** Invoke db:test:prepare (first_time)
** Invoke db:abort_if_pending_migrations (first_time)
** Invoke environment
** Invoke db:migrate:load (first_time)
** Invoke environment
** Execute db:migrate:load
** Execute db:abort_if_pending_migrations
** Execute db:test:prepare
** Execute db:drop
** Execute db:create
** Execute db:load
** Invoke db:schema:load (first_time)
** Invoke environment
** Execute db:schema:load
** Execute test:prepare
** Execute test:units
** Invoke test:functionals (first_time)
** Invoke test:prepare
** Execute test:functionals
** Invoke test:integration (first_time)
** Invoke test:prepare
** Execute test:integration
** Execute test:run
** Invoke test:decorators (first_time)
** Invoke test:prepare
** Execute test:decorators
** Execute test:cleanup
** Execute db:test:drop
** Execute db:drop
** Execute db:test_project:drop
** Invoke db:drop (first_time)
** Invoke environment
** Execute db:drop
Run options: --seed 19360

# Running tests:

EE....

Finished tests in 0.037493s, 160.0278 tests/s, 106.6852 assertions/s.

如您所见,任务是按顺序调用的,但清理任务是在测试完成之前执行的。有解决这个问题的想法吗?

尝试使用 rake 标准语法调用多个任务:

task better_test: ["test:setup", "test", "test:cleanup"]

也许这会解决您的问题。

此外,似乎 Rake 在执行之前实际上构建了它应该 运行 的所有任务的列表,并且 运行 每个任务只构建一次。例如:

task :a
task :b
task :c

task better_test: ["a", "b", "c", "b"]

结果:

$ rake better_test -t
** Invoke better_test (first_time)
** Invoke a (first_time)
** Execute a
** Invoke b (first_time)
** Execute b
** Invoke c (first_time)
** Execute c
** Execute better_test

如您所见,任务b只有一次运行(第一个)。我相信您的 test:setuptest 在某种程度上取决于 test:cleanup 任务。所以它比预期的更早被调用。

Rake::Task["test"].enhance do
  Rake::Task["test:cleanup"].invoke
end

事实证明,这与 rake 关系不大,而与 Minitest 执行测试的方式有关。我在问题中提到,rake 任务似乎以正确的顺序被调用,但测试由于某种原因稍后执行。原因是因为 Minitest 使用 ruby 内核方法 at_exit 来执行测试。测试文件在调用 rake test 时读入,但所有测试都在 ruby 程序结束时执行,即使在我的后续 rake 任务之后也是如此。这里有一篇博客文章更详细地解释了这个问题:http://blog.arkency.com/2013/06/are-we-abusing-at-exit/.