Model.new returning a pre-initialised object in class method

[sonal425chouhan]

Steps to reproduce

1. I have a Model named Project and a class method in project.rb called 'set_new_project'.

def self.set_new_project
Project.new
end

2. run the 'where' query on Project i.e a = Project.where(id: 1)
3. Call a.set_new_project

Expected behaviour

This should return an uninitialised object i.e
<Project id: nil, name: nil, description: nil>

Actual behaviour

It returns an id initialised object i.e
<Project id: 1, name: nil, description: nil>

Additional Information:

• if you run Project.new.reload in set_new_project then it will return an object with all fields initialised as that of 'a'
• if you run Project.all then it will return a

System configuration

Rails version:
Rails 5.2.0.rc1
Ruby version:
2.4.2

[rafaelfranca]

Could you create a reproduction script with this template https://github.com/rails/rails/blob/master/guides/bug_report_templates/active_record_master.rb?

[andrehjr]

Went ahead and created a template for you @sonal425chouhan https://gist.github.com/andrehjr/efda765d33883489d01ab603f7613047#file-issue35666-rb

What's happening is that when you call a 'class' method on a ActiveRecord::Relation. It creates a 'scope'. When you call Project.new, it gets created using the scope of that relation.

See:
https://github.com/rails/rails/blob/master/activerecord/lib/active_record/scoping.rb#L35-L45
https://github.com/rails/rails/blob/master/activerecord/lib/active_record/relation/delegation.rb#L102

A "quick fix" would be to calling Project.unscoped.new, which I'm not sure is the best solution.

[rails-bot]

This issue has been automatically closed because there has been no follow-up response from the original author. We currently don't have enough information in order to take action. Please reach out if you have any additional information that will help us move this issue forward.

[st0012]

IMO, initializing objects like this with scope attributes sounds legit, but the scope attributes shouldn't include primary key