Allow to use same periods for housekeeping tasks

This enables skipping a lesser housekeeping task
(incremental or full repack) by consistently
scheduling a higher task (respectively full repack or gc)
with the same period.
Cf. #34981

app/models/application_setting.rb

@@ -137,11 +137,11 @@ class ApplicationSetting < ActiveRecord::Base
   validates :housekeeping_full_repack_period,
             presence: true,
-            numericality: { only_integer: true, greater_than: :housekeeping_incremental_repack_period }
+            numericality: { only_integer: true, greater_than_or_equal_to: :housekeeping_incremental_repack_period }
   validates :housekeeping_gc_period,
             presence: true,
-            numericality: { only_integer: true, greater_than: :housekeeping_full_repack_period }
+            numericality: { only_integer: true, greater_than_or_equal_to: :housekeeping_full_repack_period }
   validates :terminal_max_session_time,
             presence: true,

changelogs/unreleased/13711-allow-same-period-housekeeping.yml

+---
+title: Allow to use same periods for different housekeeping tasks (effectively
+  skipping the lesser task)
+merge_request: 13711
+author: @cernvcs
+type: added

spec/models/application_setting_spec.rb

@@ -167,19 +167,33 @@ describe ApplicationSetting do
     context 'housekeeping settings' do
       it { is_expected.not_to allow_value(0).for(:housekeeping_incremental_repack_period) }
-      it 'wants the full repack period to be longer than the incremental repack period' do
+      it 'wants the full repack period to be at least the incremental repack period' do
         subject.housekeeping_incremental_repack_period = 2
         subject.housekeeping_full_repack_period = 1
         expect(subject).not_to be_valid
       end
-      it 'wants the gc period to be longer than the full repack period' do
-        subject.housekeeping_full_repack_period = 2
-        subject.housekeeping_gc_period = 1
+      it 'wants the gc period to be at least the full repack period' do
+        subject.housekeeping_full_repack_period = 100
+        subject.housekeeping_gc_period = 90
         expect(subject).not_to be_valid
       end
+
+      it 'allows the same period for incremental repack and full repack, effectively skipping incremental repack' do
+        subject.housekeeping_incremental_repack_period = 2
+        subject.housekeeping_full_repack_period = 2
+
+        expect(subject).to be_valid
+      end
+
+      it 'allows the same period for full repack and gc, effectively skipping full repack' do
+        subject.housekeeping_full_repack_period = 100
+        subject.housekeeping_gc_period = 100
+
+        expect(subject).to be_valid
+      end
     end
   end

spec/services/projects/housekeeping_service_spec.rb

@@ -75,7 +75,7 @@ describe Projects::HousekeepingService do
     end
   end
-  it 'uses all three kinds of housekeeping we offer' do
+  it 'goes through all three housekeeping tasks, executing only the highest task when there is overlap' do
     allow(subject).to receive(:try_obtain_lease).and_return(:the_uuid)
     allow(subject).to receive(:lease_key).and_return(:the_lease_key)