1 files changed, 59 insertions, 3 deletions

diff --git a/lib/gitlab/git/rev_list.rb b/lib/gitlab/git/rev_list.rb
index e0943d3a3eb..4974205b8fd 100644
--- a/lib/gitlab/git/rev_list.rb
+++ b/lib/gitlab/git/rev_list.rb
@@ -13,11 +13,32 @@ module Gitlab
         @path_to_repo = path_to_repo
       end
 
-      # This method returns an array of new references
+      # This method returns an array of new commit references
       def new_refs
         execute([*base_args, newrev, '--not', '--all'])
       end
 
+      # Finds newly added objects
+      # Returns an array of shas
+      #
+      # Can skip objects which do not have a path using required_path: true
+      # This skips commit objects and root trees, which might not be needed when
+      # looking for blobs
+      #
+      # When given a block it will yield objects as a lazy enumerator so
+      # the caller can limit work done instead of processing megabytes of data
+      def new_objects(require_path: nil, not_in: nil, &lazy_block)
+        args = [*base_args, newrev, *not_in_refs(not_in), '--objects']
+
+        get_objects(args, require_path: require_path, &lazy_block)
+      end
+
+      def all_objects(require_path: nil, &lazy_block)
+        args = [*base_args, '--all', '--objects']
+
+        get_objects(args, require_path: require_path, &lazy_block)
+      end
+
       # This methods returns an array of missed references
       #
       # Should become obsolete after https://gitlab.com/gitlab-org/gitaly/issues/348.
@@ -27,16 +48,27 @@ module Gitlab
 
       private
 
+      def not_in_refs(references)
+        return ['--not', '--all'] unless references
+        return [] if references.empty?
+
+        references.prepend('--not')
+      end
+
       def execute(args)
-        output, status = popen(args, nil, Gitlab::Git::Env.all.stringify_keys)
+        output, status = popen(args, nil, Gitlab::Git::Env.to_env_hash)
 
         unless status.zero?
-          raise "Got a non-zero exit code while calling out `#{args.join(' ')}`."
+          raise "Got a non-zero exit code while calling out `#{args.join(' ')}`: #{output}"
         end
 
         output.split("\n")
       end
 
+      def lazy_execute(args, &lazy_block)
+        popen(args, nil, Gitlab::Git::Env.to_env_hash, lazy_block: lazy_block)
+      end
+
       def base_args
         [
           Gitlab.config.git.bin_path,
@@ -44,6 +76,30 @@ module Gitlab
           'rev-list'
         ]
       end
+
+      def get_objects(args, require_path: nil)
+        if block_given?
+          lazy_execute(args) do |lazy_output|
+            objects = objects_from_output(lazy_output, require_path: require_path)
+
+            yield(objects)
+          end
+        else
+          object_output = execute(args)
+
+          objects_from_output(object_output, require_path: require_path)
+        end
+      end
+
+      def objects_from_output(object_output, require_path: nil)
+        object_output.map do |output_line|
+          sha, path = output_line.split(' ', 2)
+
+          next if require_path && path.blank?
+
+          sha
+        end.reject(&:nil?)
+      end
     end
   end
 end