在 RSpec 中获取'Bad value for range'

Question

下面是我的代码:

#app/models/user.rb
class User < ActiveRecord::Base
  def display_name
    name.split(' ').try(:first)
  end
end
#spec/models/user_spec.rb
require 'rails_helper'
RSpec.describe User, :type => :model do
  let(:user) { FactoryGirl.create :user }
  it "should return the correct display name" do
    expect ( user.display_name ).to eql("Chuck")
  end
end
#spec/factories/users.rb
FactoryGirl.define do
  factory :user do
    provider "MyString"
    uid "MyString"
    name "Chuck Norris"
    oauth_token "MyString"
    oauth_expires_at "2014-07-24 07:31:36"
  end
end 

但是当我运行这个规范时，我得到了以下错误:

Failure/Error: expect ( user.display_name ).to eql("Chuck")
     ArgumentError:
       bad value for range

，似乎它检查to方法从轨道active support，但我认为to应该是一个方法在rspec。以下是我的backtrace

# /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.2/lib/active_support/core_ext/string/access.rb:62:in `to'
     # ./spec/models/user_spec.rb:7:in `block (2 levels) in <top (required)>'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:148:in `instance_exec'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:148:in `block in run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:210:in `call'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:210:in `block (2 levels) in <class:Procsy>'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-rails-3.0.2/lib/rspec/rails/adapters.rb:72:in `block (2 levels) in <module:MinitestLifecycleAdapter>'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:294:in `instance_exec'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:294:in `instance_exec'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/hooks.rb:430:in `block (2 levels) in run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:210:in `call'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:210:in `block (2 levels) in <class:Procsy>'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/hooks.rb:432:in `run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/hooks.rb:485:in `run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:303:in `with_around_example_hooks'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example.rb:145:in `run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example_group.rb:494:in `block in run_examples'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example_group.rb:490:in `map'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example_group.rb:490:in `run_examples'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/example_group.rb:457:in `run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:112:in `block (2 levels) in run_specs'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:112:in `map'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:112:in `block in run_specs'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/reporter.rb:54:in `report'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:108:in `run_specs'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:86:in `run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:70:in `run'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/lib/rspec/core/runner.rb:38:in `invoke'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/gems/rspec-core-3.0.3/exe/rspec:4:in `<top (required)>'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/bin/rspec:23:in `load'
     # /Users/sameera/.rvm/gems/ruby-2.0.0-p247/bin/rspec:23:in `<main>'

我检查了这个解决方案，它不起作用。

我在

Rails 4.0.2
• Rspec 3.0.0

Answer 1

删除expect(user.display_name)之间的空格。如果需要，可以在圆括号内设置一个，但不能在圆括号前设置。

Answer 2

你能不能先给var赋值，像这样:

RSpec.describe User, :type => :model do
  let(:user) { FactoryGirl.create :user }
  it "should return the correct display name" do
    user_display_name = user.display_name
    expect (user_display_name).to eql("Chuck")
  end
end

Answer 3

使用说明:

  def display_name
    name.split(' ')[0]
  end

或更好:

  def display_name
    name.blank? ? "" : name.split(' ')[0]
  end