Remove legacy finder for LFS objects

This removes the legacy finder for LFS objects since
we made Foreign Data Wrapper (FDW) a hard requirement
for Geo on GitLab 12.0.

ee/app/finders/geo/legacy_lfs_object_registry_finder.rb

-# frozen_string_literal: true
-
-module Geo
-  class LegacyLfsObjectRegistryFinder < RegistryFinder
-    def syncable
-      current_node.lfs_objects.syncable
-    end
-  end
-end

ee/app/finders/geo/lfs_object_registry_finder.rb

@@ -23,9 +23,7 @@ module Geo
     end
 
     def syncable
-      if use_legacy_queries_for_selective_sync?
-        legacy_finder.syncable
-      elsif selective_sync?
+      if selective_sync?
         fdw_geo_node.lfs_objects.syncable
       else
         LfsObject.syncable
@@ -74,12 +72,6 @@ module Geo
 
     private
 
-    # rubocop:disable CodeReuse/Finder
-    def legacy_finder
-      @legacy_finder ||= Geo::LegacyLfsObjectRegistryFinder.new(current_node: current_node)
-    end
-    # rubocop:enable CodeReuse/Finder
-
     def fdw_geo_node
       @fdw_geo_node ||= Geo::Fdw::GeoNode.find(current_node.id)
     end

ee/spec/finders/geo/lfs_object_registry_finder_spec.rb

 require 'spec_helper'
 
-describe Geo::LfsObjectRegistryFinder, :geo do
+describe Geo::LfsObjectRegistryFinder, :geo_fdw do
   include ::EE::GeoHelpers
 
   # Using let() instead of set() because set() does not work properly
@@ -31,27 +31,6 @@ describe Geo::LfsObjectRegistryFinder, :geo do
     stub_lfs_object_storage
   end
 
-  shared_examples_for 'a file registry finder' do
-    it 'responds to file registry finder methods' do
-      file_registry_finder_methods = %i{
-        syncable
-        count_syncable
-        count_synced
-        count_failed
-        count_synced_missing_on_primary
-        count_registry
-        find_unsynced
-        find_migrated_local
-        find_retryable_failed_registries
-        find_retryable_synced_missing_on_primary_registries
-      }
-
-      file_registry_finder_methods.each do |method|
-        expect(subject).to respond_to(method)
-      end
-    end
-  end
-
   shared_examples 'counts all the things' do
     describe '#count_syncable' do
       before do
@@ -663,138 +642,25 @@ describe Geo::LfsObjectRegistryFinder, :geo do
     end
   end
 
-  context 'FDW', :geo_fdw do
-    context 'with use_fdw_queries_for_selective_sync disabled' do
-      before do
-        stub_feature_flags(use_fdw_queries_for_selective_sync: false)
-      end
+  it 'responds to file registry finder methods' do
+    file_registry_finder_methods = %i{
+      syncable
+      count_syncable
+      count_synced
+      count_failed
+      count_synced_missing_on_primary
+      count_registry
+      find_unsynced
+      find_migrated_local
+      find_retryable_failed_registries
+      find_retryable_synced_missing_on_primary_registries
+    }
 
-      include_examples 'counts all the things'
-      include_examples 'finds all the things'
+    file_registry_finder_methods.each do |method|
+      expect(subject).to respond_to(method)
     end
-
-    context 'with use_fdw_queries_for_selective_sync enabled' do
-      before do
-        stub_feature_flags(use_fdw_queries_for_selective_sync: true)
   end
 
   include_examples 'counts all the things'
   include_examples 'finds all the things'
-    end
-  end
-
-  context 'Legacy' do
-    before do
-      stub_fdw_disabled
-    end
-
-    describe '#count_syncable' do
-      before do
-        allow_any_instance_of(LfsObjectsProject).to receive(:update_project_statistics).and_return(nil)
-
-        create(:lfs_objects_project, project: synced_project, lfs_object: lfs_object_1)
-        create(:lfs_objects_project, project: synced_project_in_nested_group, lfs_object: lfs_object_2)
-        create(:lfs_objects_project, project: unsynced_project, lfs_object: lfs_object_3)
-        create(:lfs_objects_project, project: project_broken_storage, lfs_object: lfs_object_4)
-        create(:lfs_objects_project, project: project_broken_storage, lfs_object: lfs_object_5)
-      end
-
-      it 'counts LFS objects' do
-        expect(subject.count_syncable).to eq 5
-      end
-
-      it 'ignores remote LFS objects' do
-        lfs_object_1.update_column(:file_store, ObjectStorage::Store::REMOTE)
-
-        expect(subject.count_syncable).to eq 4
-      end
-
-      context 'with selective sync by namespace' do
-        before do
-          secondary.update!(selective_sync_type: 'namespaces', namespaces: [synced_group])
-        end
-
-        it 'counts LFS objects' do
-          expect(subject.count_syncable).to eq 2
-        end
-
-        it 'ignores remote LFS objects' do
-          lfs_object_1.update_column(:file_store, ObjectStorage::Store::REMOTE)
-
-          expect(subject.count_syncable).to eq 1
-        end
-      end
-
-      context 'with selective sync by shard' do
-        before do
-          secondary.update!(selective_sync_type: 'shards', selective_sync_shards: ['broken'])
-        end
-
-        it 'counts LFS objects' do
-          expect(subject.count_syncable).to eq 2
-        end
-
-        it 'ignores remote LFS objects' do
-          lfs_object_5.update_column(:file_store, ObjectStorage::Store::REMOTE)
-
-          expect(subject.count_syncable).to eq 1
-        end
-      end
-    end
-
-    describe '#count_registry' do
-      it 'counts file registries for LFS objects' do
-        create(:geo_file_registry, :lfs, file_id: lfs_object_remote_1.id)
-        create(:geo_file_registry, :lfs, file_id: lfs_object_2.id)
-        create(:geo_file_registry, :lfs, file_id: lfs_object_3.id)
-        create(:geo_file_registry, :avatar)
-
-        expect(subject.count_registry).to eq 3
-      end
-
-      context 'with selective sync by namespace' do
-        before do
-          allow_any_instance_of(LfsObjectsProject).to receive(:update_project_statistics).and_return(nil)
-
-          create(:lfs_objects_project, project: synced_project, lfs_object: lfs_object_1)
-          create(:lfs_objects_project, project: synced_project_in_nested_group, lfs_object: lfs_object_2)
-          create(:lfs_objects_project, project: unsynced_project, lfs_object: lfs_object_3)
-
-          secondary.update!(selective_sync_type: 'namespaces', namespaces: [synced_group])
-        end
-
-        it 'does not apply the selective sync restriction' do
-          create(:geo_file_registry, :lfs, file_id: lfs_object_remote_1.id)
-          create(:geo_file_registry, :lfs, file_id: lfs_object_2.id)
-          create(:geo_file_registry, :lfs, file_id: lfs_object_3.id)
-          create(:geo_file_registry, :avatar)
-
-          expect(subject.count_registry).to eq 3
-        end
-      end
-
-      context 'with selective sync by shard' do
-        before do
-          allow_any_instance_of(LfsObjectsProject).to receive(:update_project_statistics).and_return(nil)
-
-          create(:lfs_objects_project, project: synced_project, lfs_object: lfs_object_1)
-          create(:lfs_objects_project, project: synced_project_in_nested_group, lfs_object: lfs_object_2)
-          create(:lfs_objects_project, project: unsynced_project, lfs_object: lfs_object_3)
-          create(:lfs_objects_project, project: project_broken_storage, lfs_object: lfs_object_4)
-          create(:lfs_objects_project, project: project_broken_storage, lfs_object: lfs_object_remote_1)
-
-          secondary.update!(selective_sync_type: 'shards', selective_sync_shards: ['broken'])
-        end
-
-        it 'does not apply the selective sync restriction' do
-          create(:geo_file_registry, :lfs, file_id: lfs_object_remote_1.id)
-          create(:geo_file_registry, :lfs, file_id: lfs_object_2.id)
-          create(:geo_file_registry, :lfs, file_id: lfs_object_4.id)
-          create(:geo_file_registry, :avatar)
-
-          expect(subject.count_registry).to eq 3
-        end
-      end
-    end
-  end
 end