Merge branch 'sh-remove-double-caching-repo-empty' into 'master'

Remove double caching of Repository#empty?

Closes #43882

See merge request gitlab-org/gitlab-ce!17588

app/models/repository.rb

@@ -35,7 +35,7 @@ class Repository
   CACHED_METHODS = %i(size commit_count rendered_readme contribution_guide
                       changelog license_blob license_key gitignore koding_yml
                       gitlab_ci_yml branch_names tag_names branch_count
-                      tag_count avatar exists? empty? root_ref has_visible_content?
+                      tag_count avatar exists? root_ref has_visible_content?
                       issue_template_names merge_request_template_names).freeze
 
   # Methods that use cache_method but only memoize the value
@@ -360,7 +360,7 @@ class Repository
   def expire_emptiness_caches
     return unless empty?
 
-    expire_method_caches(%i(empty? has_visible_content?))
+    expire_method_caches(%i(has_visible_content?))
   end
 
   def lookup_cache
@@ -506,12 +506,14 @@ class Repository
   end
   cache_method :exists?
 
+  # We don't need to cache the output of this method because both exists? and
+  # has_visible_content? are already memoized and cached. There's no guarantee
+  # that the values are expired and loaded atomically.
   def empty?
     return true unless exists?
 
     !has_visible_content?
   end
-  cache_method :empty?
 
   # The size of this repository in megabytes.
   def size

changelogs/unreleased/sh-remove-double-caching-repo-empty.yml

+---
+title: Remove double caching of Repository#empty?
+merge_request:
+author:
+type: fixed

spec/models/repository_spec.rb

@@ -1447,7 +1447,6 @@ describe Repository do
     it 'expires the caches for an empty repository' do
       allow(repository).to receive(:empty?).and_return(true)
 
-      expect(cache).to receive(:expire).with(:empty?)
       expect(cache).to receive(:expire).with(:has_visible_content?)
 
       repository.expire_emptiness_caches
@@ -1456,7 +1455,6 @@ describe Repository do
     it 'does not expire the cache for a non-empty repository' do
       allow(repository).to receive(:empty?).and_return(false)
 
-      expect(cache).not_to receive(:expire).with(:empty?)
       expect(cache).not_to receive(:expire).with(:has_visible_content?)
 
       repository.expire_emptiness_caches