如何使用 Shoulda 测试辅助方法并设置参数和请求值？

Question

我正在使用 Rails 2.2.2，想知道如何设置参数值来测试我的辅助方法。

我找到了一些示例，可以让您使用辅助方法运行测试，但当我直接在方法中使用请求或参数值时，它对我不起作用。

require 'test_helper'

class ProductHelperTest < Test::Unit::TestCase
  include ProductHelper

  context 'ProductHelper' do
    should 'build the link' do
      assert_equal '', build_link
    end
  end
end

当使用请求或参数值时，我会收到一个错误，指出局部变量或方法未定义。我将如何设置该值？

使用请求值时应该出现错误，并且使用参数值时会出现相同的消息。

1) Error:
test: ProductHelper should build the link. (ProductHelperTest):
NameError: undefined local variable or method `request` for #<ProductHelperTest:0x33ace6c>
  /vendor/rails/actionpack/lib/action_controller/test_process.rb:471:in `method_missing`
  /app/helpers/products_helper.rb:14:in `build_link`
  ./test/unit/product_helper_test.rb:10:in `__bind_1251902384_440357`
  /vendor/gems/thoughtbot-shoulda-2.0.5/lib/shoulda/context.rb:254:in `call`
  /vendor/gems/thoughtbot-shoulda-2.0.5/lib/shoulda/context.rb:254:in `test: ProductHelper should build the link. `
  /vendor/rails/activesupport/lib/active_support/testing/setup_and_teardown.rb:94:in `__send__`
  /vendor/rails/activesupport/lib/active_support/testing/setup_and_teardown.rb:94:in `run`

Answer 1

我想您必须使用 mocha 或通过在测试中定义模拟对象来模拟对 request 和 params 的调用：

# Assuming ProductHelper implementation
module ProductHelper
  def build_link
    "#{request.path}?#{params[:id]}"
  end
end

class ProductHelperTest < Test::Unit::TestCase
  include ProductHelper

  # mock by defining a method
  def params
    { :controller => "test", :id => "23" }
  end

  # mock request.path using `mocha` # => "my_url"
  def request
    mock(:path => "my_url")
  end

  context 'ProductHelper' do
    should 'build the link' do
      assert_equal 'my_url?23', build_link
    end
  end
end

我希望这会有所帮助:)

Answer 2

这也有效：
controller.params = {:filter =>; {:user_id =>; 1}

这是一个示例：

require 'test_helper'

class BookmarksHelperTest < ActionView::TestCase

  def test_some_helper_method
    controller.params = {:filter => {:user_id => 1}
    #... Rest of your test
  end
end

Answer 3

请注意，如果您使用 Rails 2.3.x 或任何使用 ActionView::TestCase 的东西 - 那么您真正需要做的只是在测试中定义一个私有 params 方法。

例如，

require 'test_helper'

class BookmarksHelperTest < ActionView::TestCase

  context "with an applied filter of my bookmarks" do
    setup do
      expects(:applied_filters).returns({:my_bookmarks => true})
    end

    should "not be able to see it when other filters are called using my_bookmarks_filter" do
      assert_equal other_filters(:my_bookmarks), {}
    end
  end

  private

    def params
      {}
    end

end

您甚至可以通过将 params 定义为 ActionView::TestCase 内部的方法来做得更好