RSpec和ActiveRecord：示例在無效方案上失敗

Question

我是Rails的新手，並試圖用TDD和BDD編寫應用程序。

現在在其中一個模型中有一個字段長度驗證。有一個RSpec有一個例子來檢查這個特定字段的長度驗證。

下面是Model類

class Section < ActiveRecord::Base 

    # Validations 
    validates_presence_of :name, length: { maximum: 50 } 

end 

和RSpec

require 'spec_helper' 

describe Section do 
    before do 
     @section = Section.new(name:'Test') 
    end 

    subject { @section } 

    # Check for attribute accessor methods 
    it { should respond_to(:name) } 


    # Sanity check, verifying that the @section object is initially valid 
    it { should be_valid } 

    describe "when name is not present" do 
     before { @section.name = "" } 
     it { should_not be_valid } 
    end 

    describe "when name is too long" do 
     before { @section.name = "a" * 52 } 
     it { should_not be_valid } 
    end 
end 

當我敲響該規範例如失敗，以下錯誤

....F...... 

Failures: 

    1) Section when name is too long 
    Failure/Error: it { should_not be_valid } 
     expected valid? to return false, got true 
    # ./spec/models/section_spec.rb:24:in `block (3 levels) in <top (required)>' 

Finished in 0.17311 seconds 
11 examples, 1 failure 

我失去了一些東西在這裏？

另外請建議我一些參考，以瞭解如何使用RSpec（和Shoulda）測試模型，尤其是關係。

Answer 1

validates_presence_of方法沒有length選項。 您應該驗證長度validates_length_of方法：

class Section < ActiveRecord::Base 
    # Validations 
    validates_presence_of :name 
    validates_length_of :name, maximum: 50 
end 

或者使用Rails3中新的驗證語法：

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