1 files changed, 57 insertions, 0 deletions
diff --git a/lib/gitlab/ci/reports/test_suite_comparer.rb b/lib/gitlab/ci/reports/test_suite_comparer.rb
new file mode 100644
index 00000000000..642aa593092
--- /dev/null
+++ b/lib/gitlab/ci/reports/test_suite_comparer.rb
@@ -0,0 +1,57 @@
+module Gitlab
+  module Ci
+    module Reports
+      class TestSuiteComparer
+        include Gitlab::Utils::StrongMemoize
+
+        attr_reader :name, :base_suite, :head_suite
+
+        def initialize(name, base_suite, head_suite)
+          @name = name
+          @base_suite = base_suite || TestSuite.new
+          @head_suite = head_suite
+        end
+
+        def new_failures
+          strong_memoize(:new_failures) do
+            head_suite.failed.reject do |key, _|
+              base_suite.failed.include?(key)
+            end.values
+          end
+        end
+
+        def existing_failures
+          strong_memoize(:existing_failures) do
+            head_suite.failed.select do |key, _|
+              base_suite.failed.include?(key)
+            end.values
+          end
+        end
+
+        def resolved_failures
+          strong_memoize(:resolved_failures) do
+            head_suite.success.select do |key, _|
+              base_suite.failed.include?(key)
+            end.values
+          end
+        end
+
+        def total_count
+          head_suite.total_count
+        end
+
+        def total_status
+          head_suite.total_status
+        end
+
+        def resolved_count
+          resolved_failures.count
+        end
+
+        def failed_count
+          new_failures.count + existing_failures.count
+        end
+      end
+    end
+  end
+end