在视图测试中，什么时候使用 before(:all)？

Question

我正在应用程序中编写一些视图测试，我的测试需要类似以下内容：

describe 'form' do
  it 'has a search form' do
    render
    expect(rendered).to have_selector 'form[id=mock_search]'
  end
  it 'has a name filter' do
    render
    expect(rendered).to have_selector 'label[for=q_name_cont]', text: 'Nome do simulado'
    expect(rendered).to have_selector 'input[id=q_name_cont]'
  end
  it 'has a submit button' do
    render
    expect(rendered).to have_selector 'input[type=submit][value="Buscar"][name=commit]'
  end
  it 'has a reset button' do
    render
    expect(rendered).to have_selector 'input[type=submit][value="Limpar filtros"]'
  end
end

但是我和 before(:each) 在应用程序上重复太多请求，使我的测试花费 25 秒到运行。我改成 before(:all) 然后变成 4 seconds.

我还应该使用 before(:each) 吗？
为什么不推荐 before(:all)？

编辑： 我之前的迭代：

before(:each) do
  @school = build(:school)
  @teacher = build(:teacher)
  build_list(:mock_with_proccessed_statistics, 2, school: @school, teacher: @teacher)
  @mocks = Mock.page(nil)
  @q = Mock.ransack
  allow(view).to receive(:current_school).and_return(@school)
  allow(view).to receive(:format_date) { |date, format| date.strftime(format) }
end

Answer 1

before(:each) 在每个测试用例执行之前执行。和 before(:all) 在当前上下文中的所有测试用例之前一次。

Answer 2

describe 'form' do
  # 
  #let! will create create instance variable school 
  #inside your test case and assign your school build. Different between 
  #let! and let is: let! create before every task. You won't need it to put 
  #on before block and let doesn't do that you have to call it explicitly to 
  #create that mock and get values..   
  let!(:school) { build(:school) }
  let!(:teacher) { build(:teacher) }
  let!(:statistics) { build_list(:mock_with_proccessed_statistics, 2, school: @school, teacher: @teacher) }
  let!(:mocks) { Mock.page(nil) }

  subject { render }

  it 'has a search form' do
    expect{ subject }.to have_selector 'form[id=mock_search]'
  end

  it 'has a name filter' do
    expect{ subject }.to have_selector 'label[for=q_name_cont]', text: 'Nome do simulado'
    expect{ subject }.to have_selector 'input[id=q_name_cont]'
  end
end

在视图测试中，什么时候使用 before(:all)？

In views tests, when to use before(:all)?

ruby

ruby-on-rails

rspec-rails