diff --git a/api/codeception.dist.yml b/api/codeception.dist.yml
index 02eccdb..8c793f9 100644
--- a/api/codeception.dist.yml
+++ b/api/codeception.dist.yml
@@ -17,3 +17,7 @@ modules:
         dump: tests/_data/dump.sql
         cleanup: true # reload dump between tests
         populate: true # load dump before all tests
+coverage:
+  enabled: true
+  include:
+    - src/*
\ No newline at end of file
diff --git a/api/src/Repositories/AbstractWorkingHoursViewRepository.php b/api/src/Repositories/AbstractWorkingHoursViewRepository.php
index 908822a..d8a757b 100644
--- a/api/src/Repositories/AbstractWorkingHoursViewRepository.php
+++ b/api/src/Repositories/AbstractWorkingHoursViewRepository.php
@@ -101,13 +101,7 @@ abstract class AbstractWorkingHoursViewRepository implements RepositoryReaderInt
         $minutes = (int)$time_array[1];
         $seconds = (int)$time_array[2];
         $interval = new DateInterval(sprintf('PT%dH%dM%dS', abs($hours), abs($minutes), abs($seconds)));
-        if ($hours < 0) {
-            $interval->invert = 1;
-        }
-        if ($minutes < 0) {
-            $interval->invert = 1;
-        }
-        if ($seconds < 0) {
+        if (($hours < 0 || ($minutes < 0) || ($seconds < 0))) {
             $interval->invert = 1;
         }
         return $interval;