Delegate some additional methods in querying.rb

[kenta-s]

I have seen many people write code like below so far.

if Person.count.zero?
  # do something
end

if they can code like this,

if Person.empty?
  # do something
end

the code will look more like RoR.
They can use exists? method of course. But I think there should be empty? method as well.

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[pixeltrix]

@kenta-s I agree that we should delegate empty? to all the same way as any? and many?, but there's no need to add an implementation since there's already one:

https://github.com/rails/rails/blob/master/activerecord/lib/active_record/relation.rb#L279-L288

Can you modify the PR to just have the delegation, the tests and can you also add a CHANGELOG entry - thanks!

[pixeltrix]

Also the test case should live in named_scoping_test.rb since that's where the ones for any? and many? live. Try to follow the existing patterns, so your test could be as simple as:

  def test_model_class_should_respond_to_empty
    assert !Topic.empty?
    Topic.delete_all
    assert Topic.empty?
  end

Thanks!

[egilburg]

In this case none? should also be delegated (and perhaps for completeness' sake, one?) as well.

[kenta-s]

Thank you for your feedback! I will modify this PR to just have the delegation soon. and I will also check none? and one? as well :)

[kenta-s]

@pixeltrix Done. And I also added none? and one? to the delegation as @egilburg pointed out.
I would appreciate any further feedback. Thank you :)

[pixeltrix]

This could be Topic.create!

[kenta-s]

@pixeltrix Done!

[vipulnsward]

An example for each case would be good here.

Topic.empty? # => false
Topic.one? # => true
Topic.none? # => false

[kenta-s]

Updated. @vipulnsward Thank you for your feedback! :)

[pixeltrix]

@kenta-s thanks for your contribution 👍