如何测试(ActiveRecord)对象相等性 [英] How to test for (ActiveRecord) object equality

问题描述

In Ruby 1.9.2 on Rails 3.0.3, I'm attempting to test for object equality between two Friend (class inherits from ActiveRecord::Base) objects.

The objects are equal, but the test fails:

Failure/Error: Friend.new(name: 'Bob').should eql(Friend.new(name: 'Bob'))

expected #<Friend id: nil, event_id: nil, name: 'Bob', created_at: nil, updated_at: nil>
     got #<Friend id: nil, event_id: nil, name: 'Bob', created_at: nil, updated_at: nil>

(compared using eql?)

Just for grins, I also test for object identity, which fails as I'd expect:

Failure/Error: Friend.new(name: 'Bob').should equal(Friend.new(name: 'Bob'))

expected #<Friend:2190028040> => #<Friend id: nil, event_id: nil, name: 'Bob', created_at: nil, updated_at: nil>
     got #<Friend:2190195380> => #<Friend id: nil, event_id: nil, name: 'Bob', created_at: nil, updated_at: nil>

Compared using equal?, which compares object identity,
but expected and actual are not the same object. Use
'actual.should == expected' if you don't care about
object identity in this example.

Can someone explain to me why the first test for object equality fails, and how I can successfully assert those two objects are equal?

解决方案

Rails deliberately delegates equality checks to the identity column. If you want to know if two AR objects contain the same stuff, compare the result of calling #attributes on both.

这篇关于如何测试(ActiveRecord)对象相等性的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！