Fixed some issues detected by PHPstan.

src/Entity/Attachments/AttachmentContainingDBElement.php

@@ -37,7 +37,7 @@ abstract class AttachmentContainingDBElement extends NamedDBElement
     use MasterAttachmentTrait;
 
     /**
-     * @var Attachment[]
+     * @var Attachment[]|Collection
      *                   //TODO
      *                   //@ORM\OneToMany(targetEntity="Attachment", mappedBy="element")
      *

src/Entity/LogSystem/DatabaseUpdatedLogEntry.php

@@ -54,7 +54,7 @@ class DatabaseUpdatedLogEntry extends AbstractLogEntry
     /**
      * Gets the database version before update.
      *
-     * @return int
+     * @return string
      */
     public function getOldVersion(): string
     {
@@ -64,7 +64,7 @@ class DatabaseUpdatedLogEntry extends AbstractLogEntry
     /**
      * Gets the (target) database version after update.
      *
-     * @return int
+     * @return string
      */
     public function getNewVersion(): string
     {

src/Entity/Parts/PartLot.php

@@ -233,7 +233,7 @@ class PartLot extends DBElement
     /**
      * Sets the part that is stored in this part lot.
      *
-     * @param Part|InstockTrait $part
+     * @param Part $part
      *
      * @return PartLot
      */

src/Entity/Parts/PartTraits/OrderTrait.php

@@ -126,6 +126,7 @@ trait OrderTrait
      * The orderdetail is assigned to this part.
      *
      * @param Orderdetail $orderdetail the orderdetail that should be added
+     * @return $this
      */
     public function addOrderdetail(Orderdetail $orderdetail): self
     {
@@ -137,8 +138,8 @@ trait OrderTrait
 
     /**
      * Removes the given orderdetail from the list of orderdetails.
-     *
-     * @return OrderTrait
+     * @param Orderdetail $orderdetail
+     * @return $this
      */
     public function removeOrderdetail(Orderdetail $orderdetail): self
     {
@@ -158,6 +159,7 @@ trait OrderTrait
      *                                                (if the part has exactly one orderdetails,
      *                                                set this orderdetails as order orderdetails.
      *                                                Otherwise, set "no order orderdetails")
+     * @return $this
      */
     public function setManualOrder(bool $new_manual_order, int $new_order_quantity = 1, ?Orderdetail $new_order_orderdetail = null): self
     {

src/Entity/PriceInformations/Orderdetail.php

@@ -245,7 +245,7 @@ class Orderdetail extends DBElement
      *
      * @return Pricedetail|null: the price as a bcmath string. Null if there are no orderdetails for the given quantity
      */
-    public function findPriceForQty(float $quantity = 1): ?Pricedetail
+    public function findPriceForQty(float $quantity = 1.0): ?Pricedetail
     {
         if ($quantity <= 0) {
             return null;