Prevent project team from being truncated too early during project destructionsh-fix-project-team-truncation-in-destroy

There are two issues with truncating the project team early:

1. `Projects::UnlinkForkService` may not close merge requests properly since
   permissions may be revoked early.

2. If an error is encountered during flushing of caches, then the user will
   lose all privileges, possibly causing an issue on deletion on retry.

1 files changed, 19 insertions, 0 deletions

diff --git a/spec/services/projects/destroy_service_spec.rb b/spec/services/projects/destroy_service_spec.rb
index 3faa88c00a1..74bfba44dfd 100644
--- a/spec/services/projects/destroy_service_spec.rb
+++ b/spec/services/projects/destroy_service_spec.rb
@@ -50,6 +50,25 @@ describe Projects::DestroyService, services: true do
     it { expect(Dir.exist?(remove_path)).to be_truthy }
   end
 
+  context 'when flushing caches fail' do
+    before do
+      new_user = create(:user)
+      project.team.add_user(new_user, Gitlab::Access::DEVELOPER)
+      allow_any_instance_of(Projects::DestroyService).to receive(:flush_caches).and_raise(Redis::CannotConnectError)
+    end
+
+    it 'keeps project team intact upon an error' do
+      Sidekiq::Testing.inline! do
+        begin
+          destroy_project(project, user, {})
+        rescue Redis::CannotConnectError
+        end
+      end
+
+      expect(project.team.members.count).to eq 1
+    end
+  end
+
   context 'with async_execute' do
     let(:async) { true }