fix: PostObjectInterface schemaObject cache (#1397)

Author: thorbrink

library/PostObject/Decorators/PostObjectWithSchemaObject.php

@@ -42,14 +42,15 @@ public function getSchemaProperty(string $property): mixed
      */
     private function getSchemaObject(): BaseType
     {
-        static $schemaObject = null;
+        static $schemaObjectCache = [];
+        $cacheKey                 = $this->postObject->getId();
 
-        if ($schemaObject === null) {
-            $schemaObject                   = $this->schemaObjectFromPost->create($this->postObject);
-            $this->postObject->schemaObject = $schemaObject;
+        if (!isset($schemaObjectCache[$cacheKey])) {
+            $schemaObjectCache[$cacheKey]   = $this->schemaObjectFromPost->create($this->postObject);
+            $this->postObject->schemaObject = $schemaObjectCache[$cacheKey]; // TODO: remove when all usage of ->schemaObject is removed from the codebase.
         }
 
-        return $schemaObject;
+        return $schemaObjectCache[$cacheKey];
     }
 
     /**

library/PostObject/Decorators/PostObjectWithSchemaObject.test.php

@@ -29,20 +29,42 @@ public function testApplyMethodAppliesSchemaObjectToPost()
         $schemaObject         = Schema::thing()->name('Foo');
         $schemaObjectFromPost = $this->getSchemaObjectFromPostInstance();
         $schemaObjectFromPost->method('create')->willReturn($schemaObject);
+        $innerPostObject = $this->getPostObject();
+        $innerPostObject->method('getId')->willReturn(123);
 
-        $postObject = new PostObjectWithSchemaObject($this->getPostObject(), $schemaObjectFromPost);
+        $postObject = new PostObjectWithSchemaObject($innerPostObject, $schemaObjectFromPost);
 
         $this->assertSame('Thing', $postObject->getSchemaProperty('@type'));
         $this->assertSame('Foo', $postObject->getSchemaProperty('name'));
     }
 
+    /**
+     * @testdox caches schema object per post ID
+     */
+    public function testCachesSchemaObjectPerPostId()
+    {
+        // Arrange
+        $schemaObject         = Schema::thing()->name('Foo');
+        $schemaObjectFromPost = $this->getSchemaObjectFromPostInstance();
+        $innerPostObject      = $this->getPostObject();
+        $innerPostObject->method('getId')->willReturn(321);
+        $postObject = new PostObjectWithSchemaObject($this->getPostObject(), $schemaObjectFromPost);
+
+        // Assert
+        $schemaObjectFromPost->expects($this->once())->method('create')->willReturn($schemaObject);
+
+        // Act
+        $postObject->getSchemaProperty('@type');
+        $postObject->getSchemaProperty('name');
+    }
+
     private function getSchemaObjectFromPostInstance(): SchemaObjectFromPostInterface|MockObject
     {
         return $this->createMock(SchemaObjectFromPostInterface::class);
     }
 
-    private function getPostObject(): PostObjectInterface
+    private function getPostObject(): PostObjectInterface|MockObject
     {
-        return new PostObject(1, new FakeWpService());
+        return $this->createMock(PostObjectInterface::class);
     }
 }