1 files changed, 60 insertions, 18 deletions

diff --git a/app/models/repository.rb b/app/models/repository.rb
index 130daddd9d1..5a25ccb1dd6 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -15,7 +15,7 @@ class Repository
     Gitlab::Popen.popen(%W(find #{repository_downloads_path} -not -path #{repository_downloads_path} -mmin +120 -delete))
   end
 
-  def initialize(path_with_namespace, default_branch = nil, project = nil)
+  def initialize(path_with_namespace, project)
     @path_with_namespace = path_with_namespace
     @project = project
   end
@@ -44,7 +44,9 @@ class Repository
   end
 
   def empty?
-    raw_repository.empty?
+    return @empty unless @empty.nil?
+
+    @empty = cache.fetch(:empty?) { raw_repository.empty? }
   end
 
   #
@@ -57,7 +59,11 @@ class Repository
   # This method return true if repository contains some content visible in project page.
   #
   def has_visible_content?
-    raw_repository.branch_count > 0
+    return @has_visible_content unless @has_visible_content.nil?
+
+    @has_visible_content = cache.fetch(:has_visible_content?) do
+      raw_repository.branch_count > 0
+    end
   end
 
   def commit(id = 'HEAD')
@@ -78,7 +84,8 @@ class Repository
       offset: offset,
       # --follow doesn't play well with --skip. See:
       # https://gitlab.com/gitlab-org/gitlab-ce/issues/3574#note_3040520
-      follow: false
+      follow: false,
+      skip_merges: skip_merges
     }
 
     commits = Gitlab::Git::Commit.where(options)
@@ -184,8 +191,11 @@ class Repository
     cache.fetch(:"diverging_commit_counts_#{branch.name}") do
       # Rugged seems to throw a `ReferenceError` when given branch_names rather
       # than SHA-1 hashes
-      number_commits_behind = commits_between(branch.target, root_ref_hash).size
-      number_commits_ahead = commits_between(root_ref_hash, branch.target).size
+      number_commits_behind = raw_repository.
+        count_commits_between(branch.target, root_ref_hash)
+
+      number_commits_ahead = raw_repository.
+        count_commits_between(root_ref_hash, branch.target)
 
       { behind: number_commits_behind, ahead: number_commits_ahead }
     end
@@ -196,12 +206,6 @@ class Repository
        readme version contribution_guide changelog license)
   end
 
-  def branch_cache_keys
-    branches.map do |branch|
-      :"diverging_commit_counts_#{branch.name}"
-    end
-  end
-
   def build_cache
     cache_keys.each do |key|
       unless cache.exist?(key)
@@ -226,20 +230,56 @@ class Repository
     @branches = nil
   end
 
-  def expire_cache
+  def expire_cache(branch_name = nil)
     cache_keys.each do |key|
       cache.expire(key)
     end
 
-    expire_branch_cache
+    expire_branch_cache(branch_name)
   end
 
-  def expire_branch_cache
-    branches.each do |branch|
-      cache.expire(:"diverging_commit_counts_#{branch.name}")
+  # Expires _all_ caches, including those that would normally only be expired
+  # under specific conditions.
+  def expire_all_caches!
+    expire_cache
+    expire_root_ref_cache
+    expire_emptiness_caches
+    expire_has_visible_content_cache
+  end
+
+  def expire_branch_cache(branch_name = nil)
+    # When we push to the root branch we have to flush the cache for all other
+    # branches as their statistics are based on the commits relative to the
+    # root branch.
+    if !branch_name || branch_name == root_ref
+      branches.each do |branch|
+        cache.expire(:"diverging_commit_counts_#{branch.name}")
+      end
+    # In case a commit is pushed to a non-root branch we only have to flush the
+    # cache for said branch.
+    else
+      cache.expire(:"diverging_commit_counts_#{branch_name}")
     end
   end
 
+  def expire_root_ref_cache
+    cache.expire(:root_ref)
+    @root_ref = nil
+  end
+
+  # Expires the cache(s) used to determine if a repository is empty or not.
+  def expire_emptiness_caches
+    cache.expire(:empty?)
+    @empty = nil
+
+    expire_has_visible_content_cache
+  end
+
+  def expire_has_visible_content_cache
+    cache.expire(:has_visible_content?)
+    @has_visible_content = nil
+  end
+
   def rebuild_cache
     cache_keys.each do |key|
       cache.expire(key)
@@ -477,7 +517,7 @@ class Repository
   end
 
   def root_ref
-    @root_ref ||= raw_repository.root_ref
+    @root_ref ||= cache.fetch(:root_ref) { raw_repository.root_ref }
   end
 
   def commit_dir(user, path, message, branch)
@@ -588,6 +628,8 @@ class Repository
   end
 
   def merge_base(first_commit_id, second_commit_id)
+    first_commit_id = commit(first_commit_id).try(:id) || first_commit_id
+    second_commit_id = commit(second_commit_id).try(:id) || second_commit_id
     rugged.merge_base(first_commit_id, second_commit_id)
   rescue Rugged::ReferenceError
     nil