Resolve "Remove two_step_rebase feature flag"

app/models/repository.rb

@@ -1091,10 +1091,6 @@ class Repository
   end
 
   def rebase(user, merge_request, skip_ci: false)
-    if Feature.disabled?(:two_step_rebase, default_enabled: true)
-      return rebase_deprecated(user, merge_request)
-    end
-
     push_options = []
     push_options << Gitlab::PushOptions::CI_SKIP if skip_ci
 

changelogs/unreleased/29077-remove-two_step_rebase-feature-flag.yml

+---
+title: Update rebasing to use the new two-phase Gitaly Rebase RPC
+merge_request: 23546
+author:
+type: changed

spec/models/repository_spec.rb

@@ -1618,11 +1618,6 @@ describe Repository do
       end
     end
 
-    context 'when two_step_rebase feature is enabled' do
-      before do
-        stub_feature_flags(two_step_rebase: true)
-      end
-
     it_behaves_like 'a method that can rebase successfully'
 
     it 'executes the new Gitaly RPC' do
@@ -1679,22 +1674,6 @@ describe Repository do
     end
   end
 
-    context 'when two_step_rebase feature is disabled' do
-      before do
-        stub_feature_flags(two_step_rebase: false)
-      end
-
-      it_behaves_like 'a method that can rebase successfully'
-
-      it 'executes the deprecated Gitaly RPC' do
-        expect_any_instance_of(Gitlab::GitalyClient::OperationService).to receive(:user_rebase)
-        expect_any_instance_of(Gitlab::GitalyClient::OperationService).not_to receive(:rebase)
-
-        repository.rebase(user, merge_request)
-      end
-    end
-  end
-
   describe '#revert' do
     let(:new_image_commit) { repository.commit('33f3729a45c02fc67d00adb1b8bca394b0e761d9') }
     let(:update_image_commit) { repository.commit('2f63565e7aac07bcdadb654e253078b727143ec4') }

spec/services/merge_requests/rebase_service_spec.rb

@@ -71,14 +71,6 @@ describe MergeRequests::RebaseService do
 
     it_behaves_like 'sequence of failure and success'
 
-    context 'with deprecated step rebase feature' do
-      before do
-        stub_feature_flags(two_step_rebase: false)
-      end
-
-      it_behaves_like 'sequence of failure and success'
-    end
-
     context 'when unexpected error occurs' do
       before do
         allow(repository).to receive(:gitaly_operation_client).and_raise('Something went wrong')
@@ -140,21 +132,7 @@ describe MergeRequests::RebaseService do
         end
       end
 
-      context 'when the two_step_rebase feature is enabled' do
-        before do
-          stub_feature_flags(two_step_rebase: true)
-        end
-
-        it_behaves_like 'a service that can execute a successful rebase'
-      end
-
-      context 'when the two_step_rebase feature is disabled' do
-        before do
-          stub_feature_flags(two_step_rebase: false)
-        end
-
       it_behaves_like 'a service that can execute a successful rebase'
-      end
 
       context 'when skip_ci flag is set' do
         let(:skip_ci) { true }