Merge branch 'sh-remove-matching-mr-db-sync-ff' into 'master'

Drop matching_merge_request_db_sync feature flag

See merge request gitlab-org/gitlab!49644

ee/changelogs/unreleased/sh-remove-matching-mr-db-sync-ff.yml

+---
+title: Drop matching_merge_request_db_sync feature flag
+merge_request: 49644
+author:
+type: changed

ee/config/feature_flags/development/matching_merge_request_db_sync.yml

----
-name: matching_merge_request_db_sync
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/42435
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/254488
-milestone: '13.5'
-type: development
-group: group::create
-default_enabled: true

ee/lib/ee/gitlab/checks/matching_merge_request.rb

@@ -11,7 +11,6 @@ module EE
 
         override :match?
         def match?
-          return super unless ::Feature.enabled?(:matching_merge_request_db_sync, default_enabled: true)
           return super unless ::Gitlab::Database::LoadBalancing.enable?
 
           # When a user merges a merge request, the following sequence happens:

ee/spec/lib/gitlab/checks/matching_merge_request_spec.rb

@@ -40,14 +40,15 @@ RSpec.describe Gitlab::Checks::MatchingMergeRequest do
 
     context 'with load balancing enabled', :request_store, :redis do
       let(:session) { ::Gitlab::Database::LoadBalancing::Session.current }
+      let(:all_caught_up) { true }
 
-      context 'on secondary that has caught up to primary' do
       before do
-          allow(::Gitlab::Database::LoadBalancing::Sticking).to receive(:all_caught_up?).and_return(true)
         expect(::Gitlab::Database::LoadBalancing).to receive(:enable?).and_return(true)
         expect(::Gitlab::Database::LoadBalancing::Sticking).to receive(:unstick_or_continue_sticking).and_call_original
+        allow(::Gitlab::Database::LoadBalancing::Sticking).to receive(:all_caught_up?).and_return(all_caught_up)
       end
 
+      context 'on secondary that has caught up to primary' do
         it 'continues to use the secondary' do
           expect(session.use_primary?).to be false
           expect(subject.match?).to be true
@@ -61,33 +62,7 @@ RSpec.describe Gitlab::Checks::MatchingMergeRequest do
       end
 
       context 'on secondary behind primary' do
-        before do
-          allow(::Gitlab::Database::LoadBalancing::Sticking).to receive(:all_caught_up?).and_return(false)
-        end
-
-        context 'with feature flag disabled' do
-          before do
-            stub_feature_flags(matching_merge_request_db_sync: false)
-            expect(::Gitlab::Database::LoadBalancing).not_to receive(:enable?)
-            expect(::Gitlab::Database::LoadBalancing::Sticking).not_to receive(:unstick_or_continue_sticking)
-          end
-
-          it 'does not check load balancing state' do
-            expect(subject.match?).to be true
-          end
-
-          it 'increments no counters' do
-            expect { subject.match? }
-              .to change { total_counter.get }.by(0)
-              .and change { stale_counter.get }.by(0)
-          end
-        end
-
-        context 'load balancing enabled' do
-          before do
-            expect(::Gitlab::Database::LoadBalancing).to receive(:enable?).and_return(true)
-            expect(::Gitlab::Database::LoadBalancing::Sticking).to receive(:unstick_or_continue_sticking).and_call_original
-          end
+        let(:all_caught_up) { false }
 
         it 'sticks to the primary' do
           expect(subject.match?).to be true
@@ -102,5 +77,4 @@ RSpec.describe Gitlab::Checks::MatchingMergeRequest do
       end
     end
   end
-  end
 end