Add vaccinations check to school transfer rake task

lib/tasks/schools.rake

@@ -52,6 +52,20 @@ namespace :schools do
 
     raise "Could not find one or both schools." if old_loc.nil? || new_loc.nil?
 
+    unless PatientSession
+             .joins(:patient, :session)
+             .where(
+               patient: {
+                 school: old_loc
+               },
+               session: {
+                 location: old_loc
+               }
+             )
+             .all?(&:safe_to_destroy?)
+      raise "Some patient sessions at #{old_loc.urn} are not safe to destroy. Cannot complete transfer."
+    end
+
     if !new_loc.team_id.nil? && new_loc.team_id != old_loc.team_id
       raise "#{new_loc.urn} belongs to #{new_loc.team.name}. Could not complete transfer."
     end

spec/lib/tasks/schools_rake_spec.rb

@@ -51,6 +51,31 @@
     expect(school_move.school).to eq(target_school)
   end
 
+  context "when some patient sessions are not safe to destroy" do
+    let!(:patient_session) { create(:patient_session, patient:, session:) } # rubocop:disable RSpec/LetSetup
+
+    before do
+      # rubocop:disable RSpec/AnyInstance
+      allow_any_instance_of(PatientSession).to receive(
+        :safe_to_destroy?
+      ).and_return(false)
+      # rubocop:enable RSpec/AnyInstance
+    end
+
+    it "raises an error and does not transfer records" do
+      expect { invoke }.to raise_error(
+        RuntimeError,
+        /Some patient sessions at #{source_school.urn} are not safe to destroy/
+      )
+
+      expect(patient.reload.school).to eq(source_school)
+      expect(consent_form.reload.school).to eq(source_school)
+      expect(consent_form.reload.location).to eq(source_school)
+      expect(session.reload.location).to eq(source_school)
+      expect(school_move.reload.school).to eq(source_school)
+    end
+  end
+
   context "when source school ID is invalid" do
     let(:source_urn) { "999999" }