Make Api\SearchResults implement Api\SearchResultsInterface

app/code/Magento/Catalog/Api/Data/CategoryAttributeSearchResultsInterface.php

@@ -24,5 +24,5 @@ public function getItems();
      * @param \Magento\Catalog\Api\Data\CategoryAttributeInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Catalog/Api/Data/ProductAttributeSearchResultsInterface.php

@@ -24,5 +24,5 @@ public function getItems();
      * @param \Magento\Catalog\Api\Data\ProductAttributeInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Catalog/Api/Data/ProductSearchResultsInterface.php

@@ -24,5 +24,5 @@ public function getItems();
      * @param \Magento\Catalog\Api\Data\ProductInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/CatalogInventory/Api/Data/StockCollectionInterface.php

@@ -30,5 +30,5 @@ public function getItems();
      * @param \Magento\CatalogInventory\Api\Data\StockInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/CatalogInventory/Api/Data/StockItemCollectionInterface.php

@@ -30,7 +30,7 @@ public function getItems();
      * @param \Magento\CatalogInventory\Api\Data\StockItemInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 
     /**
      * Get search criteria.

app/code/Magento/CatalogInventory/Api/Data/StockStatusCollectionInterface.php

@@ -27,7 +27,7 @@ public function getItems();
      * @param \Magento\CatalogInventory\Api\Data\StockStatusInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 
     /**
      * Get search criteria.

app/code/Magento/Cms/Api/Data/BlockSearchResultsInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Cms\Api\Data\BlockInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Cms/Api/Data/PageSearchResultsInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Cms\Api\Data\PageInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Customer/Api/Data/AddressSearchResultsInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Customer\Api\Data\AddressInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Customer/Api/Data/CustomerSearchResultsInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Customer\Api\Data\CustomerInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Customer/Api/Data/GroupSearchResultsInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Customer\Api\Data\GroupInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Eav/Api/Data/AttributeGroupSearchResultsInterface.php

@@ -21,5 +21,5 @@ public function getItems();
      * @param \Magento\Eav\Api\Data\AttributeGroupInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Eav/Api/Data/AttributeSearchResultsInterface.php

@@ -21,5 +21,5 @@ public function getItems();
      * @param \Magento\Eav\Api\Data\AttributeInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Eav/Api/Data/AttributeSetSearchResultsInterface.php

@@ -21,5 +21,5 @@ public function getItems();
      * @param \Magento\Eav\Api\Data\AttributeSetInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Quote/Api/Data/CartSearchResultsInterface.php

@@ -35,7 +35,7 @@ public function getItems();
      * @param \Magento\Quote\Api\Data\CartInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 
     /**
      * Get search criteria.
@@ -50,7 +50,7 @@ public function getSearchCriteria();
      * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
      * @return $this
      */
-    public function setSearchCriteria(\Magento\Framework\Api\SearchCriteriaInterface $searchCriteria = null);
+    public function setSearchCriteria(\Magento\Framework\Api\SearchCriteriaInterface $searchCriteria);
 
     /**
      * Get total count.

app/code/Magento/Sales/Api/Data/CreditmemoCommentSearchResultInterface.php

@@ -29,5 +29,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\CreditmemoCommentInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/CreditmemoItemSearchResultInterface.php

@@ -29,5 +29,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\CreditmemoItemInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/CreditmemoSearchResultInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\CreditmemoInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/InvoiceCommentSearchResultInterface.php

@@ -27,5 +27,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\InvoiceCommentInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/InvoiceItemSearchResultInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\InvoiceItemInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/InvoiceSearchResultInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\InvoiceInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/OrderAddressSearchResultInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\OrderAddressInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/OrderItemSearchResultInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\OrderItemInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/OrderPaymentSearchResultInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\OrderPaymentInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/OrderStatusHistorySearchResultInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\OrderStatusHistoryInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/ShipmentCommentSearchResultInterface.php

@@ -27,5 +27,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\ShipmentCommentInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/ShipmentItemSearchResultInterface.php

@@ -27,5 +27,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\ShipmentItemInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/ShipmentSearchResultInterface.php

@@ -29,5 +29,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\ShipmentInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/ShipmentTrackSearchResultInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\ShipmentTrackInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Sales/Api/Data/TransactionSearchResultInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Sales\Api\Data\TransactionInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Tax/Api/Data/TaxClassSearchResultsInterface.php

@@ -25,5 +25,5 @@ public function getItems();
      * @param \Magento\Tax\Api\Data\TaxClassInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Tax/Api/Data/TaxRateSearchResultsInterface.php

@@ -28,5 +28,5 @@ public function getItems();
      * @param \Magento\Tax\Api\Data\TaxRateInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Tax/Api/Data/TaxRuleSearchResultsInterface.php

@@ -25,5 +25,5 @@ public function getItems();
      * @param \Magento\Tax\Api\Data\TaxRuleInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

app/code/Magento/Tax/Test/Unit/Model/TaxClass/RepositoryTest.php

@@ -222,6 +222,7 @@ public function testGetList()
 
         $collection->expects($this->any())->method('getSize')->willReturn(2);
         $collection->expects($this->any())->method('setItems')->with([$taxClassOne, $taxClassTwo]);
+        $collection->expects($this->any())->method('getItems')->willReturn([$taxClassOne, $taxClassTwo]);
         $collection->expects($this->once())->method('setCurPage')->with(0);
         $collection->expects($this->once())->method('setPageSize')->with(20);
 

app/code/Magento/Ui/Api/Data/BookmarkSearchResultsInterface.php

@@ -26,5 +26,5 @@ public function getItems();
      * @param \Magento\Ui\Api\Data\BookmarkInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 }

lib/internal/Magento/Framework/Api/SearchResults.php

@@ -9,7 +9,7 @@
 /**
  * SearchResults Service Data Object used for the search service requests
  */
-class SearchResults extends AbstractSimpleObject
+class SearchResults extends AbstractSimpleObject implements SearchResultsInterface
 {
     const KEY_ITEMS = 'items';
     const KEY_SEARCH_CRITERIA = 'search_criteria';
@@ -49,10 +49,10 @@ public function getSearchCriteria()
     /**
      * Set search criteria
      *
-     * @param \Magento\Framework\Api\SearchCriteria $searchCriteria
+     * @param SearchCriteriaInterface $searchCriteria
      * @return $this
      */
-    public function setSearchCriteria(\Magento\Framework\Api\SearchCriteria $searchCriteria)
+    public function setSearchCriteria(\Magento\Framework\Api\SearchCriteriaInterface $searchCriteria)
     {
         return $this->setData(self::KEY_SEARCH_CRITERIA, $searchCriteria);
     }

lib/internal/Magento/Framework/Api/SearchResultsInterface.php

@@ -26,7 +26,7 @@ public function getItems();
      * @param \Magento\Framework\Api\ExtensibleDataInterface[] $items
      * @return $this
      */
-    public function setItems(array $items = null);
+    public function setItems(array $items);
 
     /**
      * Get search criteria.
@@ -41,7 +41,7 @@ public function getSearchCriteria();
      * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
      * @return $this
      */
-    public function setSearchCriteria(\Magento\Framework\Api\SearchCriteriaInterface $searchCriteria = null);
+    public function setSearchCriteria(\Magento\Framework\Api\SearchCriteriaInterface $searchCriteria);
 
     /**
      * Get total count.