Introduce Repository#with_repo_branch_commit

We merge repository checks inside it so we don't have to
check it on the call site, and we could also load the commit
for the caller. This greatly reduce code duplication.

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7237#note_20572919

1 files changed, 16 insertions, 9 deletions

diff --git a/app/models/repository.rb b/app/models/repository.rb
index 46995bdcb33..b1a789492d3 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -1063,19 +1063,26 @@ class Repository
     Gitlab::Popen.popen(args, path_to_repo).first.lines.map(&:strip)
   end
 
-  def with_tmp_ref(source_repository, source_branch_name)
-    tmp_ref = "refs/tmp/#{SecureRandom.hex}/head"
+  def with_repo_branch_commit(source_repository, source_branch_name)
+    branch_name_or_sha =
+      if source_repository == self
+        source_branch_name
+      else
+        tmp_ref = "refs/tmp/#{SecureRandom.hex}/head"
 
-    fetch_ref(
-      source_repository.path_to_repo,
-      "#{Gitlab::Git::BRANCH_REF_PREFIX}#{source_branch_name}",
-      tmp_ref
-    )
+        fetch_ref(
+          source_repository.path_to_repo,
+          "#{Gitlab::Git::BRANCH_REF_PREFIX}#{source_branch_name}",
+          tmp_ref
+        )
+
+        source_repository.commit(source_branch_name).sha
+      end
 
-    yield
+    yield(commit(branch_name_or_sha))
 
   ensure
-    rugged.references.delete(tmp_ref)
+    rugged.references.delete(tmp_ref) if tmp_ref
   end
 
   def fetch_ref(source_path, source_ref, target_ref)