如何测试validate_uniqueness_of？

Question

我遇到了一个心理障碍。有人能给我解释一下如何为validate_uniqueness_of写一个规范测试吗？

Answer 1

或者使用Shoulda：

before do
  @user = Factory(:user)
end

subject { @user }

it { should validate_uniqueness_of(:name) }

Answer 2

class Foo < ActiveRecord::Base
  validates_uniqueness_of :name
end

# spec
describe Foo do
  it "should have a unique name" do
    Foo.create!(:name=>"Foo")
    foo = Foo.new(:name=>"Foo")
    foo.should_not be_valid
    foo.errors[:name].should include("has already been taken")
  end
end

Answer 3

使用Shoulda让它变得简短：

it "validates uniqueness of name" do
  FactoryGirl.create(:tag, name: 'unique name')
  should validate_uniqueness_of(:name)
end