1 files changed, 53 insertions, 0 deletions
diff --git a/lib/gitlab/ci/reports/reports_comparer.rb b/lib/gitlab/ci/reports/reports_comparer.rb
new file mode 100644
index 00000000000..d413d3a74f6
--- /dev/null
+++ b/lib/gitlab/ci/reports/reports_comparer.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    module Reports
+      class ReportsComparer
+        include Gitlab::Utils::StrongMemoize
+
+        STATUS_SUCCESS = 'success'
+        STATUS_FAILED = 'failed'
+
+        attr_reader :base_report, :head_report
+
+        def initialize(base_report, head_report)
+          @base_report = base_report
+          @head_report = head_report
+        end
+
+        def status
+          success? ? STATUS_SUCCESS : STATUS_FAILED
+        end
+
+        def success?
+          raise NotImplementedError
+        end
+
+        def existing_errors
+          raise NotImplementedError
+        end
+
+        def new_errors
+          raise NotImplementedError
+        end
+
+        def resolved_errors
+          raise NotImplementedError
+        end
+
+        def errors_count
+          raise NotImplementedError
+        end
+
+        def resolved_count
+          resolved_errors.size
+        end
+
+        def total_count
+          existing_errors.size + new_errors.size
+        end
+      end
+    end
+  end
+end