[Added] phpstan + phpstan file

composer.json

@@ -45,8 +45,9 @@
   },
   "require": {
     "php": ">=7.1",
-    "oxid-esales/oxideshop-ce": "v6.0 - 6.3",
-    "google/apiclient":" ^2.0"
+    "oxid-esales/oxideshop-ce": "v6.0 - v6.3",
+    "google/apiclient":"^2.0",
+    "phpstan/phpstan": "^1.8"
   },
   "autoload": {
     "psr-4": {

phpstan.neon

@@ -3,8 +3,8 @@ parameters:
         - IntelliSenseHelper.php
         - ../../oxid-esales/oxideshop-ce/source/oxfunctions.php
         - ../../oxid-esales/oxideshop-ce/source/overridablefunctions.php
-    level: 9
-    phpVersion: 70100
+    paths:
+        - ./
+    level: 0
+    phpVersion: 70200
     checkMissingIterableValueType: false
-    ignoreErrors:
-        - '#Psr\\Container\\ContainerExceptionInterface is not subtype of Throwable#'