Add latest changes from gitlab-org/gitlab@13-12-stable-eev13.12.0-rc42

1 files changed, 40 insertions, 0 deletions

diff --git a/lib/gitlab/pagination/keyset/iterator.rb b/lib/gitlab/pagination/keyset/iterator.rb
new file mode 100644
index 00000000000..3bc8c0bf616
--- /dev/null
+++ b/lib/gitlab/pagination/keyset/iterator.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Pagination
+    module Keyset
+      class Iterator
+        def initialize(scope:, use_union_optimization: false)
+          @scope = scope
+          @order = Gitlab::Pagination::Keyset::Order.extract_keyset_order_object(scope)
+          @use_union_optimization = use_union_optimization
+        end
+
+        # rubocop: disable CodeReuse/ActiveRecord
+        def each_batch(of: 1000)
+          cursor_attributes = {}
+
+          loop do
+            current_scope = scope.dup.limit(of)
+            relation = order
+              .apply_cursor_conditions(current_scope, cursor_attributes, { use_union_optimization: @use_union_optimization })
+              .reorder(order)
+              .limit(of)
+
+            yield relation
+
+            last_record = relation.last
+            break unless last_record
+
+            cursor_attributes = order.cursor_attributes_for_node(last_record)
+          end
+        end
+        # rubocop: enable CodeReuse/ActiveRecord
+
+        private
+
+        attr_reader :scope, :order
+      end
+    end
+  end
+end