使用 RSpec 测试多个 Rails 控制器的 RESTful 操作会产生大量代码重复。下面的代码是我第一次尝试使用共享示例来 DRY 事情。
以下是我不喜欢代码的地方，找不到更好的方法，希望您帮助改进：
- 共享示例要求在控制器规范(高耦合(
let块内设置特定变量。我尝试使用模型名称来推断工厂名称并在共享示例中创建测试数据。创建记录和记录变量效果很好。但是，某些模型需要存在关联，并且FactoryGirl.attributes_for不会创建关联的记录，因此验证失败。因此，valid_attributes为不同的模型创建的方式不同。我能想到的在共享示例中创建valid_attributes的唯一(可能不好的(方法是传递一个字符串，其中包含用于创建属性的代码并在共享示例中对其进行评估(eval( - 断言重定向的测试使用
eval来调用 Rails 的路由/路径帮助程序。此应用中的不同控制器具有不同的重定向行为。创建或更新记录后，某些控制器重定向到 #show 操作，其他控制器重定向到 #index。问题是，当期望重定向到 #show AFAIK 时，我们必须知道记录 ID 才能构建预期的 URL。而且我们不知道控制器规范中的记录 ID。我们只在共享的例子中知道它。那么，如果我们还不知道预期的重定向 URL 是什么(因为我们不知道记录 ID(，我们如何才能将预期的重定向 URL 从控制器规范传递到共享示例？
另外，如果您发现任何其他问题，请告诉我。
控制器规格：
# spec/controllers/quotes_controller_spec.rb
require "rails_helper"
RSpec.describe QuotesController, :focus, :type => :controller do
login_admin
let(:model) { Quote }
let(:record) { FactoryGirl.create(:quote) }
let(:records) { FactoryGirl.create_pair(:quote) }
let(:valid_attributes) { FactoryGirl.attributes_for(:quote, quote: "New quote") }
let(:invalid_attributes) { valid_attributes.update(quote: nil) }
include_examples "GET #index"
include_examples "GET #show"
include_examples "GET #new"
include_examples "GET #edit"
include_examples "POST #create", "quote_path(assigns(:quote))"
include_examples "PATCH #update", "quote_url"
include_examples "DELETE #destroy", "quotes_url"
end
共享示例：
# spec/support/shared_examples/controller_restful_actions.rb
def ivar_name(model, plural: false)
if plural
model.name.pluralize.underscore.to_sym
else
model.name.underscore.to_sym
end
end
def record_name(model)
model.name.underscore.to_sym
end
RSpec.shared_examples "GET #index" do
describe "GET #index" do
it "requires login" do
sign_out current_user
get :index
expect(response).to require_login
end
it "enforces authorization" do
get :index
expect(controller).to enforce_authorization
end
it "populates instance variable with an array of records" do
get :index
expect(assigns(ivar_name(model, plural: true))).to match_array(records)
end
end
end
RSpec.shared_examples "GET #show" do
describe "GET #show" do
it "requires login" do
sign_out current_user
get :show, id: record
expect(response).to require_login
end
it "enforces authorization" do
get :show, id: record
expect(controller).to enforce_authorization
end
it "assigns the requested record to an instance variable" do
get :show, id: record
expect(assigns(ivar_name(model))).to eq(record)
end
end
end
RSpec.shared_examples "GET #new" do
describe "GET #new" do
it "requires login" do
sign_out current_user
get :new
expect(response).to require_login
end
it "enforces authorization" do
get :new
expect(controller).to enforce_authorization
end
it "assigns a new record to an instance variable" do
get :new
expect(assigns(ivar_name(model))).to be_a_new(model)
end
end
end
RSpec.shared_examples "GET #edit" do
describe "GET #edit" do
let(:record) { FactoryGirl.create(factory_name(model)) }
it "requires login" do
sign_out current_user
get :edit, id: record
expect(response).to require_login
end
it "enforces authorization" do
get :edit, id: record
expect(controller).to enforce_authorization
end
it "assigns the requested record to an instance variable" do
get :edit, id: record
expect(assigns(ivar_name(model))).to eq(record)
end
end
end
RSpec.shared_examples "POST #create" do |redirect_path_helper|
describe "POST #create" do
it "requires login" do
sign_out current_user
post :create, { record_name(model) => valid_attributes }
expect(response).to require_login
end
it "enforces authorization" do
post :create, { record_name(model) => valid_attributes }
expect(controller).to enforce_authorization
end
context "with valid attributes" do
it "saves the new record in the database" do
expect{
post :create, { record_name(model) => valid_attributes }
}.to change(model, :count).by(1)
end
it "assigns a newly created but unsaved record to an instance variable" do
post :create, { record_name(model) => valid_attributes }
expect(assigns(ivar_name(model))).to be_a(model)
expect(assigns(ivar_name(model))).to be_persisted
end
it "redirects to #{redirect_path_helper}" do
post :create, { record_name(model) => valid_attributes }
expect(response).to redirect_to(eval(redirect_path_helper))
end
end
context "with invalid attributes" do
it "does not save the new record in the database" do
expect{
post :create, { record_name(model) => invalid_attributes }
}.not_to change(model, :count)
end
it "assigns a newly created but unsaved record an instance variable" do
post :create, { record_name(model) => invalid_attributes }
expect(assigns(ivar_name(model))).to be_a_new(model)
end
it "re-renders the :new template" do
post :create, { record_name(model) => invalid_attributes }
expect(response).to render_template(:new)
end
end
end
end
RSpec.shared_examples "PATCH #update" do |redirect_path_helper|
describe "PATCH #update" do
let(:record) { FactoryGirl.create(factory_name(model)) }
it "requires login" do
sign_out current_user
patch :update, { :id => record, record_name(model) => valid_attributes }
expect(response).to require_login
end
it "enforces authorization" do
patch :update, { :id => record, record_name(model) => valid_attributes }
expect(controller).to enforce_authorization
end
context "with valid attributes" do
it "updates the requested record" do
patch :update, { :id => record, record_name(model) => valid_attributes }
record.reload
expect(record).to have_attributes(valid_attributes)
end
it "assigns the requested record to an instance variable" do
put :update, { :id => record, record_name(model) => valid_attributes }
expect(assigns(ivar_name(model))).to eq(record)
end
it "redirects to #{redirect_path_helper}" do
patch :update, { :id => record, record_name(model) => valid_attributes }
expect(response).to redirect_to(eval(redirect_path_helper))
end
end
context "with invalid attributes" do
it "does not update the requested record" do
expect {
patch :update, { :id => record, record_name(model) => invalid_attributes }
}.not_to change { record.reload.attributes }
end
it "assigns the record to an instance variable" do
patch :update, { :id => record, record_name(model) => invalid_attributes }
expect(assigns(ivar_name(model))).to eq(record)
end
it "re-renders the :edit template" do
patch :update, { :id => record, record_name(model) => invalid_attributes }
expect(response).to render_template(:edit)
end
end
end
end
RSpec.shared_examples "DELETE #destroy" do |redirect_path_helper|
describe "DELETE #destroy" do
it "requires login" do
sign_out current_user
delete :destroy, id: record
expect(response).to require_login
end
it "enforces authorization" do
delete :destroy, id: record
expect(controller).to enforce_authorization
end
it "deletes the record" do
# Records are lazily created. Here we must force its creation.
record
expect{
delete :destroy, id: record
}.to change(model, :count).by(-1)
end
it "redirects to #{redirect_path_helper}" do
delete :destroy, id: record
expect(response).to redirect_to(eval(redirect_path_helper))
end
end
end
可能不是答案，但评论太长了：
首先，您可以将所有这些包装在一个shared_examples_for块中，例如
shared_examples_for 'a CRUD Controller' do
context "GET #index" do
it "requires login" do
sign_out current_user
get :index
expect(response).to require_login
end
####
end
context "GET #show" do
it "requires login" do
sign_out current_user
get :show, id: record
expect(response).to require_login
end
####
end
end
其次，您可以在共享示例中共享示例，以上可以是
shared_examples_for 'a CRUD Controller' do
shared_examples_for 'authenticatable' do |view:,params:{}|
it "requires login" do
sign_out current_user
get view, **params
expect(response).to require_login
end
end
context "GET #index" do
it_behaves_like 'authenticatable', view: :index
####
end
context "GET #show" do
it_behaves_like 'authenticatable', view: :show, id: record
####
end
end
第三，您可以在it_behaves_like块内分配变量，例如。
RSpec.describe QuotesController, :focus, :type => :controller do
login_admin
it_behaves_like 'a CRUD Controller' do
let(:model) { Quote }
let(:record) { FactoryGirl.create(:quote) }
let(:records) { FactoryGirl.create_pair(:quote) }
let(:valid_attributes) { FactoryGirl.attributes_for(:quote, quote: "New quote") }
let(:invalid_attributes) { valid_attributes.update(quote: nil) }
end
end
第四，这也可以简化
shared_examples_for 'a CRUD Controller' do |model:|
singular,plural = 2.times.map { |n| model.name.pluralize(n).underscore.to_sym }
let(:record) { FactoryGirl.create(singular)
let(:records) {FactoryGirl.create_pair(singular) }
let(:valid_attributes) do
# build should create the nested associations correctly as long
# as your factories are right
FactoryGirl.build(singular).attributes.delete_if do |k,_|
# this is because ActiveRecord#attributes contains columns
# you don't want to be considered updateable
["id","created_at","updated_at"].include?(k)
end
end
let(:invalid_attributes) do
# create an :invalid trait in your factory so that
# you don't have to worry about the model
FactoryGirl.build(singular, :invalid).attributes.delete_if do |k,_|
["id","created_at","updated_at"].include?(k)
end
end
####
end
RSpec.describe QuotesController, :focus, :type => :controller do
login_admin
it_behaves_like 'a CRUD Controller', model: Quote
end
最后，您会发现使用记忆let!将有很大帮助，因为您正在这些测试中创建大量记录。这将大大降低性能，如果您获得具有某些全局唯一属性的模型，您的测试将在任何地方失败。
希望这有助于开始为您指明正确的方向
更新以控制测试操作
shared_examples_for 'a CRUD Controller' do |model:|
accessible_method = ->(meth) { public_methods.include?(meth) }
context "GET #index", if: controller.method_defined?(:index) do
it_behaves_like 'authenticatable', view: :index
####
end
context "GET #show", if: controller.method_defined?(:show) do
it_behaves_like 'authenticatable', view: :show, id: record
####
end
end
这是改进的代码(基于工程师的建议(。欢迎任何进一步改进的建议。
控制器规格：
# spec/controllers/quotes_controller_spec.rb
require "rails_helper"
RSpec.describe QuotesController, :type => :controller do
it_behaves_like "a CRUD controller",
model: Quote,
create_redirect_path_helper: "quote_path(assigns(:quote))",
update_redirect_path_helper: "quote_url",
delete_redirect_path_helper: "quotes_url"
end
分享的例子：
# spec/support/shared_examples/controller_restful_actions.rb
RSpec.shared_examples "a CRUD controller" do |model:,
create_redirect_path_helper:,
update_redirect_path_helper:,
delete_redirect_path_helper:|
def self.controller_has_action?(action)
described_class.action_methods.include?(action.to_s)
end
resource_singular = model.name.underscore.to_sym
resource_plural = model.name.pluralize.underscore.to_sym
before(:each) { login_admin }
let(:record) { FactoryGirl.create(resource_singular) }
let(:records) { FactoryGirl.create_pair(resource_singular) }
# Models that validate the presence of associated records require some
# hacking in the factory to include associations in the attributes_for output.
let(:valid_attributes) { FactoryGirl.attributes_for(resource_singular) }
# All factories must have a trait called :invalid
let(:invalid_attributes) do
FactoryGirl.attributes_for(resource_singular, :invalid)
end
describe "GET #index", if: controller_has_action?(:index) do
it "requires login" do
logout
get :index
expect(response).to require_login_web
end
it "enforces authorization" do
get :index
expect(controller).to enforce_authorization
end
it "populates @#{resource_plural} with an array of #{resource_plural}" do
# Force records to be created before the request.
records
get :index
# Required when testing the User model, or else the user created
# by the Devise login helper skews the result of this test.
expected_records = assigns(resource_plural) - [@current_user]
expect(expected_records).to match_array(records)
end
end
describe "GET #show", if: controller_has_action?(:show) do
it "requires login" do
logout
get :show, id: record
expect(response).to require_login_web
end
it "enforces authorization" do
get :show, id: record
expect(controller).to enforce_authorization
end
it "assigns the requested #{resource_singular} to an instance variable" do
get :show, id: record
expect(assigns(resource_singular)).to eq(record)
end
end
describe "GET #new", if: controller_has_action?(:new) do
it "requires login" do
logout
get :new
expect(response).to require_login_web
end
it "enforces authorization" do
get :new
expect(controller).to enforce_authorization
end
it "assigns a new #{resource_singular} to @#{resource_singular}" do
get :new
expect(assigns(resource_singular)).to be_a_new(model)
end
end
describe "GET #edit", if: controller_has_action?(:edit) do
it "requires login" do
logout
get :edit, id: record
expect(response).to require_login_web
end
it "enforces authorization" do
get :edit, id: record
expect(controller).to enforce_authorization
end
it "assigns #{resource_singular} to @#{resource_singular}" do
get :edit, id: record
expect(assigns(resource_singular)).to eq(record)
end
end
describe "POST #create", if: controller_has_action?(:create) do
it "requires login" do
logout
post :create, { resource_singular => valid_attributes }
expect(response).to require_login_web
end
it "enforces authorization" do
post :create, { resource_singular => valid_attributes }
expect(controller).to enforce_authorization
end
context "with valid attributes" do
it "saves the new #{resource_singular} in the database" do
expect{
post :create, { resource_singular => valid_attributes }
}.to change(model, :count).by(1)
end
it "assigns the saved #{resource_singular} to @#{resource_singular}" do
post :create, { resource_singular => valid_attributes }
expect(assigns(resource_singular)).to be_an_instance_of(model)
expect(assigns(resource_singular)).to be_persisted
end
it "redirects to #{create_redirect_path_helper}" do
post :create, { resource_singular => valid_attributes }
expect(response).to redirect_to(eval(create_redirect_path_helper))
end
end
context "with invalid attributes" do
it "does not save the new #{resource_singular} in the database" do
expect{
post :create, { resource_singular => invalid_attributes }
}.not_to change(model, :count)
end
it "assigns the unsaved #{resource_singular} to @#{resource_singular}" do
post :create, { resource_singular => invalid_attributes }
expect(assigns(resource_singular)).to be_a_new(model)
end
it "re-renders the :new template" do
post :create, { resource_singular => invalid_attributes }
expect(response).to render_template(:new)
end
end
end
describe "PATCH #update", if: controller_has_action?(:update) do
it "requires login" do
logout
patch :update, { :id => record,
resource_singular => valid_attributes }
expect(response).to require_login_web
end
it "enforces authorization" do
patch :update, { :id => record,
resource_singular => valid_attributes }
expect(controller).to enforce_authorization
end
context "with valid attributes" do
it "updates the requested #{resource_singular}" do
patch :update, { :id => record,
resource_singular => valid_attributes }
record.reload
# Required when testing Devise's User model with reconfirmable on
record.try(:confirm)
expect(record).to have_attributes(valid_attributes)
end
it "assigns the #{resource_singular} to @#{resource_singular}" do
put :update, { :id => record,
resource_singular => valid_attributes }
expect(assigns(resource_singular)).to eq(record)
end
it "redirects to #{update_redirect_path_helper}" do
patch :update, { :id => record,
resource_singular => valid_attributes }
expect(response).to redirect_to(eval(update_redirect_path_helper))
end
end
context "with invalid attributes" do
it "does not update the #{resource_singular}" do
# Do not attempt to "refactor" the following to any of the following:
# not_to change { quote }
# not_to change { quote.attributes }
# not_to have_attributes(invalid_attributes)
# None of the above will work. See
# https://github.com/rspec/rspec-expectations/issues/996#issuecomment-310729685
expect {
patch :update, { :id => record,
resource_singular => invalid_attributes }
}.not_to change { record.reload.attributes }
end
it "assigns the #{resource_singular} to @#{resource_singular}" do
patch :update, { :id => record,
resource_singular => invalid_attributes }
expect(assigns(resource_singular)).to eq(record)
end
it "re-renders the :edit template" do
patch :update, { :id => record,
resource_singular => invalid_attributes }
expect(response).to render_template(:edit)
end
end
end
describe "DELETE #destroy", if: controller_has_action?(:destroy) do
it "requires login" do
logout
delete :destroy, id: record
expect(response).to require_login_web
end
it "enforces authorization" do
delete :destroy, id: record
expect(controller).to enforce_authorization
end
it "deletes the #{resource_singular}" do
# Force record to be created before the `expect` block.
# Otherwise, it is both created and deleted INSIDE the block, causing the
# count not to change.
record
expect{
delete :destroy, id: record
}.to change(model, :count).by(-1)
end
it "redirects to #{delete_redirect_path_helper}" do
delete :destroy, id: record
expect(response).to redirect_to(eval(delete_redirect_path_helper))
end
end
end
对于let块，如果像redirect_path_helper一样将模型作为参数传递给共享示例，它不起作用吗？
include_examples "GET #index", Quote
然后在您的shared_example您可以使用record_name方法从 FactoryGirl 创建record和records，并从那里生成valid_attributes和invalid_attributes(您也可以为无效属性创建一个:invalid_quote工厂，不确定这是否被认为是 FactoryGirl 的好做法/想法(。
对于第二个问题，您不需要使用命名的路由帮助程序，url_for(controller: :quote)和url_for(@quote)都应该都可以工作。