Merge branch 'faster-rebase-poc' into 'master'

Changed files used for sparse checkout

See merge request gitlab-org/gitaly!1611

2 files changed, 15 insertions, 1 deletions

diff --git a/changelogs/unreleased/faster-rebase-poc.yml b/changelogs/unreleased/faster-rebase-poc.yml
new file mode 100644
index 000000000..508b436e6
--- /dev/null
+++ b/changelogs/unreleased/faster-rebase-poc.yml
@@ -0,0 +1,5 @@
+---
+title: Changed files used for sparse checkout
+merge_request: 1611
+author:
+type: performance
diff --git a/ruby/lib/gitlab/git/repository.rb b/ruby/lib/gitlab/git/repository.rb
index e269ea72c..8979153c4 100644
--- a/ruby/lib/gitlab/git/repository.rb
+++ b/ruby/lib/gitlab/git/repository.rb
@@ -358,7 +358,16 @@ module Gitlab
           remote_repo_path = remote_repository.path
         end
 
-        with_worktree(worktree, branch, env: env) do
+        diff_range = "#{branch}...#{remote_branch}"
+        diff_files = begin
+                       run_git!(
+                         %W[diff --name-only #{diff_range}]
+                       ).chomp
+                     rescue GitError
+                       []
+                     end
+
+        with_worktree(worktree, branch, sparse_checkout_files: diff_files, env: env) do
           run_git!(
             %W[pull --rebase #{remote_repo_path} #{remote_branch}],
             chdir: worktree.path, env: env, include_stderr: true