Add specs for snippet_repository replication helper

- Added specs for in_replicables_for_current_secondary? to
  EE:SnippetRepostiory

Relates to https://gitlab.com/gitlab-org/gitlab/issues/287763

ee/spec/models/snippet_repository_spec.rb

@@ -11,7 +11,7 @@ RSpec.describe SnippetRepository, :request_store, :geo, type: :model do
     stub_current_geo_node(node)
   end
 
-  describe '#replicables_for_current_secondary' do
+  context 'with 3 groups, 2 projects, and 5 snippets' do
     let(:group_1) { create(:group) }
     let(:group_2) { create(:group) }
     let(:nested_group_1) { create(:group, parent: group_1) }
@@ -30,6 +30,53 @@ RSpec.describe SnippetRepository, :request_store, :geo, type: :model do
     let!(:snippet_repository_4) { create(:snippet_repository) }
     let!(:snippet_repository_5) { create(:snippet_repository, snippet: project_snippet_2) }
 
+    describe '#in_replicables_for_current_secondary?' do
+      it 'all returns true if all are replicated' do
+        [
+          snippet_repository_1,
+          snippet_repository_2,
+          snippet_repository_3,
+          snippet_repository_4,
+          snippet_repository_5
+        ].each do |repository|
+          expect(repository.in_replicables_for_current_secondary?).to be true
+        end
+      end
+
+      context 'with selective sync by namespace' do
+        before do
+          node.update!(selective_sync_type: 'namespaces', namespaces: [group_1])
+        end
+
+        it 'returns true for snippets in the namespace' do
+          expect(snippet_repository_1.in_replicables_for_current_secondary?).to be true
+        end
+
+        it 'returns true for personal snippets' do
+          expect(snippet_repository_2.in_replicables_for_current_secondary?).to be true
+        end
+
+        it 'returns false for project snippets not in an included namespace' do
+          expect(snippet_repository_5.in_replicables_for_current_secondary?).to be false
+        end
+      end
+
+      context 'with selective sync by shard' do
+        before do
+          node.update!(selective_sync_type: 'shards', selective_sync_shards: ['default'])
+        end
+
+        it 'returns true for snippets in the shard' do
+          expect(snippet_repository_1.in_replicables_for_current_secondary?).to be true
+        end
+
+        it 'returns false for project snippets not in an included shard' do
+          expect(snippet_repository_3.in_replicables_for_current_secondary?).to be false
+        end
+      end
+    end
+
+    describe '#replicables_for_current_secondary' do
       it 'returns all snippet_repositories without selective sync' do
         expect(described_class.replicables_for_current_secondary(1..described_class.last.id)).to match_array([
           snippet_repository_1,
@@ -72,4 +119,5 @@ RSpec.describe SnippetRepository, :request_store, :geo, type: :model do
         expect(described_class.replicables_for_current_secondary(1..described_class.last.id)).to be_empty
       end
     end
+  end
 end