We could simply count the commitsuse-count_commits-directly

2 files changed, 3 insertions, 2 deletions

diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index e4d8f486c77..7c69617a49f 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -887,7 +887,8 @@ class MergeRequest < ActiveRecord::Base
   def compute_diverged_commits_count
     return 0 unless source_branch_sha && target_branch_sha
 
-    Gitlab::Git::Commit.between(target_project.repository.raw_repository, source_branch_sha, target_branch_sha).size
+    target_project.repository
+      .count_commits_between(source_branch_sha, target_branch_sha)
   end
   private :compute_diverged_commits_count
 
diff --git a/lib/gitlab/git/repository.rb b/lib/gitlab/git/repository.rb
index a6e7c410bdd..563f56ac549 100644
--- a/lib/gitlab/git/repository.rb
+++ b/lib/gitlab/git/repository.rb
@@ -505,7 +505,7 @@ module Gitlab
 
       # Counts the amount of commits between `from` and `to`.
       def count_commits_between(from, to)
-        Commit.between(self, from, to).size
+        count_commits(ref: "#{from}..#{to}")
       end
 
       # Returns the SHA of the most recent common ancestor of +from+ and +to+