Broaden set of theses returned by not_consented_to_proquest scope

Why these changes are being introduced:

This is a similar issue to the one solved in #1108, but in the
not_consented_to_proquest scope. Here, the scope excludes all
theses with an author ProQuest consent value of 'true'. This
works in most cases, except when one author has opted in and
another hasn't, that thesis should still be partially harvested.
With the current logic, it will not show up in the export preview
because the scope sees a 'true' consent value and thus excludes
the thesis.

Relevant ticket(s):

* https://mitlibraries.atlassian.net/browse/ETD-603

How this addresses that need:

This inverts the logic of the not_consented_to_proquest scope.
Instead of excluding theses with at least one ProQuest consent
value of true, it includes theses with at least one ProQuest consent
value of false or nil, using the 'or' method to return the union.

Side effects of this change:

Since 'includes' is not compatible with the 'or' method, the scope
now uses 'left_joins' to load the author records. This also means
that the the result will be an ActiveRecord assocation rather than
an array. ActiveJob does not accept associations as params, so
we are now casting the params as arrays. I've done with this with
both the full and partial export sets to avoid confusion, even
though it's only needed at this stage for the partial export set.

app/controllers/thesis_controller.rb

@@ -141,7 +141,7 @@ def proquest_export_preview
  # TODO: we need to generate and send a budget report CSV for partially harvested theses (spec TBD).
  def proquest_export
  if Thesis.ready_for_proquest_export.any?
- ProquestExportJob.perform_later(Thesis.partial_proquest_export, Thesis.full_proquest_export)
+ ProquestExportJob.perform_later(Thesis.partial_proquest_export.to_a, Thesis.full_proquest_export.to_a)
  flash[:success] = 'The theses you selected will be exported. ' \
  'Status updates are not immediate.'
  else

app/models/thesis.rb

@@ -122,7 +122,8 @@ class Thesis < ApplicationRecord
  .where(authors: { proquest_allowed: nil }))
  }
  scope :not_consented_to_proquest, lambda {
- excluding(includes(authors: :user).where(authors: { proquest_allowed: true }))
+ left_joins(authors: :user).where(authors: { proquest_allowed: nil })
+ .or(where(authors: { proquest_allowed: false }))
  }
  scope :exported_to_proquest, -> { where(proquest_exported: ['Partial harvest', 'Full harvest']) }
  scope :not_exported_to_proquest, -> { where(proquest_exported: 'Not exported') }

test/models/thesis_test.rb

@@ -1318,17 +1318,33 @@ def attach_file_with_purpose_to(thesis, purpose = 'thesis_pdf')
  thesis = theses(:one)
  assert_not_includes Thesis.not_consented_to_proquest, thesis
 
+ # multi-author thesis that has opted in is excluded
+ thesis = theses(:two)
+ assert_not_includes Thesis.not_consented_to_proquest, thesis
+
  # multi-author thesis with all opt-outs is included
  thesis = theses(:with_hold)
  assert_includes Thesis.not_consented_to_proquest, thesis
 
- # multi-author thesis with one opt-in and one opt-out is excluded
+ # multi-author thesis with one opt-in and one opt-out is included
  thesis = theses(:doctor)
- assert_not_includes Thesis.not_consented_to_proquest, thesis
+ assert_includes Thesis.not_consented_to_proquest, thesis
 
- # multi-author thesis that has opted in is excluded
- thesis = theses(:two)
- assert_not_includes Thesis.not_consented_to_proquest, thesis
+ # multi-author thesis with one opt-in and one null is included
+ assert_equal 2, thesis.authors.count
+ first_author = thesis.authors.first
+ second_author = thesis.authors.second
+ assert_equal true, first_author.proquest_allowed
+ assert_equal false, second_author.proquest_allowed
+
+ second_author.proquest_allowed = nil
+ second_author.save
+ assert_includes Thesis.not_consented_to_proquest, thesis
+
+ # multi-author thesis with one opt-out and one null is included
+ first_author.proquest_allowed = false
+ first_author.save
+ assert_includes Thesis.not_consented_to_proquest, thesis
  end
 
  test 'exported_to_proquest scope includes theses flagged for partial harvest' do