1 files changed, 29 insertions, 0 deletions
diff --git a/lib/gitlab/marker_range.rb b/lib/gitlab/marker_range.rb
new file mode 100644
index 00000000000..50a59adebdf
--- /dev/null
+++ b/lib/gitlab/marker_range.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+# It is a Range object extended with `mode` attribute
+# MarkerRange not only keeps information about changed characters, but also
+# the type of changes
+module Gitlab
+  class MarkerRange < Range
+    DELETION = :deletion
+    ADDITION = :addition
+
+    # Converts Range object to MarkerRange class
+    def self.from_range(range)
+      return range if range.is_a?(self)
+
+      new(range.begin, range.end, exclude_end: range.exclude_end?)
+    end
+
+    def initialize(first, last, exclude_end: false, mode: nil)
+      super(first, last, exclude_end)
+      @mode = mode
+    end
+
+    def to_range
+      Range.new(self.begin, self.end, self.exclude_end?)
+    end
+
+    attr_reader :mode
+  end
+end