ruby-on-rails - Rails 4 和 RSpec 3 : Testing models and allow_blank

Question

我在测试模型验证时遇到问题，allow_blank。我对 RSpec 比较陌生，但在这种情况下，我认为问题在于验证。

这是我的模型:

class ComicBook < ActiveRecord::Base
  belongs_to :user

  # ensure a user_id is present
  validates :user_id, presence: true

  # ensure that title is present and at least 3 characters long
  validates :title, length: { minimum: 3 }, presence: true

  # ensure publisher is present and is at least 2 characters long
  validates :publisher, length: { minimum: 2 }, presence: true

  # ensure issue number is present and is at least 1 integer long.
  validates :issue_number, length: { minimum: 1 }, numericality: true, presence: true

  # ensure writer is is at least 2 characters long, allow to be blank
  validates :writer, length: {minimum: 2}, allow_blank: true

  # ensure illustrator is is at least 2 characters long, allow to be blank
  validates :illustrator, length: {minimum: 2}, allow_blank: true

  # ensures summary is at least than 100 characters long, allow to be blank
  validates :summary, length: { maximum: 100  }, allow_blank: true
end

这是我的规范:

describe "Comic Book" do
  it "is valid with a user id, title, publisher name, issue number and summary" do
    comic_book = ComicBook.new(
      user_id:       1,
      title:         'The Best Comic Book',
      publisher:     'IPC',
      issue_number:  1,
      writer:        'GW',
      illustrator:   'GI',
      summary:       'This comic book is good.  That is all.'
    )
    expect(comic_book).to be_valid
  end

  it "is invalid without a user_id" do
    expect(ComicBook.new(user_id: nil)).not_to be_valid
  end

  it "is invalid without a title" do
    expect(ComicBook.new(title: nil)).not_to be_valid
  end

  it "is invalid without a publisher name" do
     expect(ComicBook.new(publisher: nil)).not_to be_valid
  end

  it "is invalid without a issue number" do
    expect(ComicBook.new(issue_number: nil)).not_to be_valid
  end

  it "is valid without a writer" do
    expect(ComicBook.new(writer: "")).to be_valid
  end

  it "is valid without an illustrator" do
    expect(ComicBook.new(illustrator: "" )).to be_valid
  end

  it "is valid without a summary" do
     expect(ComicBook.new(summary: "")).to be_valid
  end
end

输出:

Failures:

      1) Comic Book is valid without a summary
         Failure/Error: expect(ComicBook.new(summary: "")).to be_valid
           expected #<ComicBook id: nil, title: nil, publisher: nil, issue_number: nil, summary: "", created_at: nil, updated_at: nil, user_id: nil, writer: nil, illustrator: nil> to be valid, but got errors: User can't be blank, Title is too short (minimum is 3 characters), Title can't be blank, Publisher is too short (minimum is 2 characters), Publisher can't be blank, Issue number is too short (minimum is 1 character), Issue number is not a number, Issue number can't be blank
         # ./spec/models/comic_book_spec.rb:41:in `block (2 levels) in <top (required)>'

      2) Comic Book is valid without a writer
         Failure/Error: expect(ComicBook.new(writer: " ")).to be_valid
           expected #<ComicBook id: nil, title: nil, publisher: nil, issue_number: nil, summary: nil, created_at: nil, updated_at: nil, user_id: nil, writer: " ", illustrator: nil> to be valid, but got errors: User can't be blank, Title is too short (minimum is 3 characters), Title can't be blank, Publisher is too short (minimum is 2 characters), Publisher can't be blank, Issue number is too short (minimum is 1 character), Issue number is not a number, Issue number can't be blank
         # ./spec/models/comic_book_spec.rb:33:in `block (2 levels) in <top (required)>'

      3) Comic Book is valid without an illustrator
         Failure/Error: expect(ComicBook.new(illustrator: "" )).to be_valid
           expected #<ComicBook id: nil, title: nil, publisher: nil, issue_number: nil, summary: nil, created_at: nil, updated_at: nil, user_id: nil, writer: nil, illustrator: ""> to be valid, but got errors: User can't be blank, Title is too short (minimum is 3 characters), Title can't be blank, Publisher is too short (minimum is 2 characters), Publisher can't be blank, Issue number is too short (minimum is 1 character), Issue number is not a number, Issue number can't be blank
         # ./spec/models/comic_book_spec.rb:37:in `block (2 levels) in <top (required)>'

    Finished in 1.06 seconds (files took 2.36 seconds to load)
    10 examples, 3 failures

    Failed examples:

    rspec ./spec/models/comic_book_spec.rb:40 # Comic Book is valid without a summary
    rspec ./spec/models/comic_book_spec.rb:32 # Comic Book is valid without a writer
    rspec ./spec/models/comic_book_spec.rb:36 # Comic Book is valid without an illustrator

如您所见，最后三个规范未通过。我也试过将 illustrator、writer 和 summary 的值设置为 nil，但没有成功。

Answer 1

问题是它无效。您不仅要检查摘要中是否存在错误，还要检查整个模型。这将在标题存在时失败，例如，在最后一个。您可以检查特定错误，或者只使用类似 https://github.com/thoughtbot/shoulda-matchers 的内容使大部分过程自动化。