Fix CachedProviderTestCase to allow changing values when projecting t…

…o cache, to take in consideration that pre-projection callables can change this values (#41)

README.md

@@ -609,7 +609,21 @@ public function getCustomerDataDataProvider(): array
             $args, // Arguments to your method (int this case: [123 <- $customerId])
             $item, // Projection item to search in cache (e.g. new CustomerByIdProjectionItem(123))
             $projectedItem, // Projected item to be return by the projection repository (null to simulate a cache miss)
-            $expectedProviderData, // Expected result
+            $providerData, // Expected result
+            // Optional, by default is null and only required when you are doing manipulations on your cached provider
+            // before projecting the item to the cache.
+            //
+            // To test this cases you can change the item as you expect it before doing the projection
+            // The $item received here is a clone of the $item defined above and if $providerData is iterable it is already
+            // injected in the item via the storeData method
+            function($itemToProject) {
+                // Do something to the item before adding it to the cache
+                // E.g. set a property on the item that usually is set on the pre-projection callables of the
+                // getAndCacheData method of the cached provider              
+                $itemToProject->setField('a value');
+
+                return $itemToProject;
+            }
         ]
     ]; 
 }

src/TestCase/Provider/CachedProviderTestCase.php

@@ -26,14 +26,16 @@ abstract class CachedProviderTestCase extends TestCase
      * @param ProjectionItemIterableInterface      $item
      * @param ProjectionItemIterableInterface|null $projectedItem
      * @param iterable|null                        $providerData
+     * @param callable|null                        $preProjection
      */
     public function testGetAndCacheData(
         $originalProvider,
         string $method,
         array $args,
         ProjectionItemIterableInterface $item,
         ?ProjectionItemIterableInterface $projectedItem,
-        ?iterable $providerData
+        ?iterable $providerData,
+        ?callable $preProjection = null
     ): void {
         // Get from cache
         ($repository = $this->getProjectionRepository())
@@ -44,11 +46,16 @@ public function testGetAndCacheData(
 
         // Cache miss
         if (null === $projectedItem && is_iterable($providerData)) {
+            $itemToProject = (clone $item)->storeData($providerData);
+            if (is_callable($preProjection)) {
+                $itemToProject = $preProjection($itemToProject);
+            }
+
             // Get data from provider
             $repository
                 ->expects($this->once())
                 ->method('add')
-                ->with((clone $item)->storeData($providerData));
+                ->with($itemToProject);
         }
 
         $result = call_user_func_array([$this->getProvider($originalProvider), $method], $args);