Rails 6(边缘) 'test_helper'，'rails_helper'，'spec_helper‘-有什么区别？

Question

我运行的是Rails 6应用程序(边缘分支)，默认情况下它附带了一个test_helper.rb文件，默认情况下，所有空测试都需要该文件：

require 'test_helper'

class UserTest < ActiveSupport::TestCase
  # test "the truth" do
  #   assert true
  # end
end

我对Rails的测试很陌生，当我读到其他宝石(如https://github.com/chrisalley/pundit-matchers)的信息时，他们都提到'spec_helper‘和'rails_helper’文件，但从来没有提到'test_helper‘。

它们都提到了调整_helper文件中的配置设置，但是我的默认test_helper文件如下所示：

ENV['RAILS_ENV'] ||= 'test'
require_relative '../config/environment'
require 'rails/test_help'

class ActiveSupport::TestCase
  # Run tests in parallel with specified workers
  parallelize(workers: :number_of_processors)

  # Setup all fixtures in test/fixtures/*.yml for all tests in alphabetical order.
  fixtures :all

  # Add more helper methods to be used by all tests here...
end

没有配置区域..。我在这里写什么才能得到它？

编辑：

所以我运行了rails generate rspec:install并生成了：

  create  .rspec
  create  spec
  create  spec/spec_helper.rb
  create  spec/rails_helper.rb

我想我还是有点困惑，为什么rails 6会为我提供一个test 目录，如果我要重新构建它呢？。

我想我的问题是，默认情况下(在test目录中)，与spec目录中提供的内容相比，什么功能不那么强大。例如，将上面的test_helper.rb与下面的spec_helper.rb进行比较：

# This file was generated by the `rails generate rspec:install` command. Conventionally, all
# specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
# The generated `.rspec` file contains `--require spec_helper` which will cause
# this file to always be loaded, without a need to explicitly require it in any
# files.
#
# Given that it is always loaded, you are encouraged to keep this file as
# light-weight as possible. Requiring heavyweight dependencies from this file
# will add to the boot time of your test suite on EVERY test run, even for an
# individual file that may not need all of that loaded. Instead, consider making
# a separate helper file that requires the additional dependencies and performs
# the additional setup, and require it from the spec files that actually need
# it.
#
# See http://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
RSpec.configure do |config|
  # rspec-expectations config goes here. You can use an alternate
  # assertion/expectation library such as wrong or the stdlib/minitest
  # assertions if you prefer.
  config.expect_with :rspec do |expectations|
    # This option will default to `true` in RSpec 4. It makes the `description`
    # and `failure_message` of custom matchers include text for helper methods
    # defined using `chain`, e.g.:
    #     be_bigger_than(2).and_smaller_than(4).description
    #     # => "be bigger than 2 and smaller than 4"
    # ...rather than:
    #     # => "be bigger than 2"
    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
  end

  # rspec-mocks config goes here. You can use an alternate test double
  # library (such as bogus or mocha) by changing the `mock_with` option here.
  config.mock_with :rspec do |mocks|
    # Prevents you from mocking or stubbing a method that does not exist on
    # a real object. This is generally recommended, and will default to
    # `true` in RSpec 4.
    mocks.verify_partial_doubles = true
  end

  # This option will default to `:apply_to_host_groups` in RSpec 4 (and will
  # have no way to turn it off -- the option exists only for backwards
  # compatibility in RSpec 3). It causes shared context metadata to be
  # inherited by the metadata hash of host groups and examples, rather than
  # triggering implicit auto-inclusion in groups with matching metadata.
  config.shared_context_metadata_behavior = :apply_to_host_groups

# The settings below are suggested to provide a good initial experience
# with RSpec, but feel free to customize to your heart's content.
=begin
  # This allows you to limit a spec run to individual examples or groups
  # you care about by tagging them with `:focus` metadata. When nothing
  # is tagged with `:focus`, all examples get run. RSpec also provides
  # aliases for `it`, `describe`, and `context` that include `:focus`
  # metadata: `fit`, `fdescribe` and `fcontext`, respectively.
  config.filter_run_when_matching :focus

  # Allows RSpec to persist some state between runs in order to support
  # the `--only-failures` and `--next-failure` CLI options. We recommend
  # you configure your source control system to ignore this file.
  config.example_status_persistence_file_path = "spec/examples.txt"

  # Limits the available syntax to the non-monkey patched syntax that is
  # recommended. For more details, see:
  #   - http://rspec.info/blog/2012/06/rspecs-new-expectation-syntax/
  #   - http://www.teaisaweso.me/blog/2013/05/27/rspecs-new-message-expectation-syntax/
  #   - http://rspec.info/blog/2014/05/notable-changes-in-rspec-3/#zero-monkey-patching-mode
  config.disable_monkey_patching!

  # Many RSpec users commonly either run the entire suite or an individual
  # file, and it's useful to allow more verbose output when running an
  # individual spec file.
  if config.files_to_run.one?
    # Use the documentation formatter for detailed output,
    # unless a formatter has already been configured
    # (e.g. via a command-line flag).
    config.default_formatter = "doc"
  end

  # Print the 10 slowest examples and example groups at the
  # end of the spec run, to help surface which specs are running
  # particularly slow.
  config.profile_examples = 10

  # Run specs in random order to surface order dependencies. If you find an
  # order dependency and want to debug it, you can fix the order by providing
  # the seed, which is printed after each run.
  #     --seed 1234
  config.order = :random

  # Seed global randomization in this process using the `--seed` CLI option.
  # Setting this allows you to use `--seed` to deterministically reproduce
  # test failures related to randomization by passing the same `--seed` value
  # as the one that triggered the failure.
  Kernel.srand config.seed
=end
end

Answer 1

您之所以获得test_helper.rb文件而不是spec_helper.rb文件，是因为rails附带了Minitest作为编写测试的默认框架，另一方面，rails可以使用其他测试框架，如您所提到的安装它的Rspec。

在这种情况下，例如https://github.com/chrisalley/pundit-matchers，它说这是一组用于测试专家的RSpec匹配器，所以在本例中，您需要使用Rspec才能使用这个匹配器。如果您想继续使用Minitest，您可能必须使用类似的matchers选项，但对于Minitest则是如此。

Rspec或Minispec是否更好地取决于项目和组织的不同方面，但这两个选项都是编写测试的强大选项。

在Stack溢出中有更多与Rspec和Minitest中的配置相关的文章，例如：

helper.rb？我需要它吗？。

您还可以查看Rspec和极小的文档。

还有一些工具可以将您的最小文件转换为Rspec文件，如：

rspec