Updates documentation with valid string interpolation syntax

[naveedkakal]

Bumped into this while copy pasting some code from the docs.

[brendon]

Thanks @naveedkakal :)

[brendon]

Wait a minute, if you use double quotes the interpolation will happen straight away. Normally we don't want this, we want the string to be interpolated in relation to the current record.

Can you double check this for me? Might have to revert this doc.

[naveedkakal]

I think you may be right - let's revert it for now.

[naveedkakal]

define_method :scope_condition do
  eval "%{#{scope}}"
 end

Looks like this is what I missed - i didn't realize it was an eval happening there.

Apologies!

[brendon]

That's all good :)

[brendon]

No worries man, it's a messed up configuration syntax anyway!

[naveedkakal]

Interestingly the thing I was trying to solve for is actually an open issue with the PG::DEADLOCK issues.

For my case what I really needed to do is have some logic around the scoping attribute

acts_as_list scope: '#{plan_id ? "plan_id = \'" + plan_id + "\'": "1=0"}'

I was tinkering with a PR for acts_as_list to also accept a proc as a scope - do you think something like that would be a good idea? My reasons for it were related to another known issue so this may be just be a workaround that doesn't belong as supported functionality.

Any thoughts?

[brendon]

Accepting a proc might be a good idea. Alternatively you can override the scope_condition and scope_changed? methods to do what you want. This is an example:

  def scope_condition
    ['notice_area_id = ? AND ? >= CURDATE()', notice_area_id, end_date]
  end

  # A custom acts_as_list scope requires a custom scoped_changed? method
  def scope_changed?
    changed.include?('notice_area_id') ||
    changed.include?('end_date') && (
      changes['end_date'][0] >= Time.zone.now.beginning_of_day &&
      changes['end_date'][1] < Time.zone.now.beginning_of_day ||
      changes['end_date'][1] >= Time.zone.now.beginning_of_day &&
      changes['end_date'][0] < Time.zone.now.beginning_of_day
    )
  end

I hope that helps :)