Don't use the redis set cache yet

For zero-downtime deployed in a mixed code environment between 12.2 and
12.3, the branch and tag name cache is incorrectly invalidated - a push
to an old machine will not clear the redis set version of the cache on
the new machine.

This commit ensures that, in 12.3, both set and non-set versions of the
cache are invalidated, but does not write or consult the set version of
the cache. . In 12.4, it will be safe to switch branch and tag names to
the redis set cache both it and the legacy cache will be invalidated
appropriately in such a mixed code environment.

This delays the full implementation of the feature by one release, but
in the absence of a credible feature-flagging strategy, and amidst an
abundance of caution about the effects of too-eager cache expiration, I
believe this is the best approach available to us.

1 files changed, 11 insertions, 41 deletions

diff --git a/spec/models/repository_spec.rb b/spec/models/repository_spec.rb
index 79395fcc994..419e1dc2459 100644
--- a/spec/models/repository_spec.rb
+++ b/spec/models/repository_spec.rb
@@ -1223,66 +1223,36 @@ describe Repository do
   end
 
   describe '#branch_exists?' do
-    let(:branch) { repository.root_ref }
+    it 'uses branch_names' do
+      allow(repository).to receive(:branch_names).and_return(['foobar'])
 
-    subject { repository.branch_exists?(branch) }
-
-    it 'delegates to branch_names when the cache is empty' do
-      repository.expire_branches_cache
-
-      expect(repository).to receive(:branch_names).and_call_original
-      is_expected.to eq(true)
-    end
-
-    it 'uses redis set caching when the cache is filled' do
-      repository.branch_names # ensure the branch name cache is filled
-
-      expect(repository)
-        .to receive(:branch_names_include?)
-        .with(branch)
-        .and_call_original
-
-      is_expected.to eq(true)
+      expect(repository.branch_exists?('foobar')).to eq(true)
+      expect(repository.branch_exists?('master')).to eq(false)
     end
   end
 
   describe '#tag_exists?' do
-    let(:tag) { repository.tags.first.name }
-
-    subject { repository.tag_exists?(tag) }
-
-    it 'delegates to tag_names when the cache is empty' do
-      repository.expire_tags_cache
-
-      expect(repository).to receive(:tag_names).and_call_original
-      is_expected.to eq(true)
-    end
-
-    it 'uses redis set caching when the cache is filled' do
-      repository.tag_names # ensure the tag name cache is filled
-
-      expect(repository)
-        .to receive(:tag_names_include?)
-        .with(tag)
-        .and_call_original
+    it 'uses tag_names' do
+      allow(repository).to receive(:tag_names).and_return(['foobar'])
 
-      is_expected.to eq(true)
+      expect(repository.tag_exists?('foobar')).to eq(true)
+      expect(repository.tag_exists?('master')).to eq(false)
     end
   end
 
-  describe '#branch_names', :clean_gitlab_redis_cache do
+  describe '#branch_names', :use_clean_rails_memory_store_caching do
     let(:fake_branch_names) { ['foobar'] }
 
     it 'gets cached across Repository instances' do
       allow(repository.raw_repository).to receive(:branch_names).once.and_return(fake_branch_names)
 
-      expect(repository.branch_names).to match_array(fake_branch_names)
+      expect(repository.branch_names).to eq(fake_branch_names)
 
       fresh_repository = Project.find(project.id).repository
       expect(fresh_repository.object_id).not_to eq(repository.object_id)
 
       expect(fresh_repository.raw_repository).not_to receive(:branch_names)
-      expect(fresh_repository.branch_names).to match_array(fake_branch_names)
+      expect(fresh_repository.branch_names).to eq(fake_branch_names)
     end
   end