do not get thumb from entity with no post ID, add diff function to entities and repositories, simple collection diff test

src/classes/entities/class-tainacan-entity.php

@@ -361,4 +361,14 @@ class Entity {
 		return get_post_type_capabilities((object) $args);
 	}
 	
+	/**
+	 * Compare this entity props with self old values or with $which other entity 
+	 * @param Entity|integer|\WP_Post $which default ($which = 0) to self compare with stored entity
+	 * @return array
+	 */
+	public function diff($which = 0) {
+		global ${$this->repository};
+		return ${$this->repository}->diff($which, $this);
+	}
+	
 }

src/classes/repositories/class-tainacan-repository.php

@@ -285,7 +285,9 @@ abstract class Repository {
     		$property = get_term_meta($entity->WP_Term->term_id, $prop, true);
     	} elseif ( isset( $entity->WP_Post )) {
     		if($mapped == 'thumbnail'){
+    			if(isset($entity->WP_Post->ID)) {
     				$property = get_the_post_thumbnail_url($entity->WP_Post->ID, 'full');
+    			}
 		    } else {
 			    $property = isset($entity->WP_Post->$mapped) ? $entity->WP_Post->$mapped : null;
 		    }
@@ -317,7 +319,7 @@ abstract class Repository {
     
     /**
      * 
-     * @param integer|\WP_Post $post
+     * @param integer|\WP_Post $post|Entity
      * @throws \Exception
      * @return \Tainacan\Entities\Entity|boolean
      */
@@ -503,6 +505,45 @@ abstract class Repository {
     	return user_can($user, $entity_cap->publish_posts, $entity->get_id());
     }
     
+    /**
+     * Compare two repository entities 
+     * 
+     * @param Entity|integer|\WP_Post $old default ($which = 0) to self compare with stored entity
+     * @param Entity|integer|\WP_Post $new
+     * 
+     * @return array List of diff values
+     */
+    public function diff($old = 0, $new) {
+    	$old_entity = null;
+    	if($old === 0) { // self diff or other entity?
+    		$id = $new->get_id();
+    		if(!empty($id)) { // there is a repository entity?
+    			$old_entity = $this->get_entity_by_post($new->WP_Post->ID);
+    		}
+    		else {
+    			$entity_type = get_class($new);
+    			$old_entity = new $entity_type; // there is no saved entity, let compare with a new empty one
+    		}
+    	}
+    	else { // get entity from repository
+    		$old_entity = $this->get_entity_by_post($old);
+    	}
+    	$new_entity = $this->get_entity_by_post($new);
+    	
+    	$map = $this->get_map();
+    	
+    	$diff = [];
+    	
+    	foreach ($map as $prop => $mapped) {
+   			if($old_entity->get_mapped_property($prop) != $new_entity->get_mapped_property($prop) ) {
+   				$diff[$prop] = ['new' => $new_entity->get_mapped_property($prop), 'old' => $old_entity->get_mapped_property($prop)];
+   			}
+    	}
+    	$diff = apply_filters('tainacan-entity-diff', $diff, $new, $old);
+    	
+    	return $diff;
+    }
+    
 }
 
 ?>

tests/test-collections.php

@@ -219,4 +219,29 @@ class Collections extends TAINACAN_UnitTestCase {
     	global $Tainacan_Collections;
     	$this->assertTrue(has_action('init', array($Tainacan_Collections, 'register_post_type')) !== false, 'Collections Init is not registred!');
     }
+    
+    /**
+     * @group diff
+     */
+    function test_diff() {
+    	$x = $this->tainacan_entity_factory->create_entity(
+    		'collection',
+    		array(
+    			'name'          => 'testeDiff',
+    			'description'   => 'adasdasdsa',
+    			'default_order' => 'DESC'
+    		),
+    		true
+    	);
+    	
+    	$x->set_name('OtherValue');
+    	$x->set_description('testeDiff2');
+    	
+    	$diff = $x->diff();
+    	$this->assertEquals(2, count($diff));
+    	$this->assertEquals($diff['name']['new'], 'OtherValue');
+    	$this->assertEquals($diff['name']['old'], 'testeDiff');
+    	$this->assertEquals($diff['description']['new'], 'testeDiff2');
+    	$this->assertEquals($diff['description']['old'], 'adasdasdsa');
+    }
 }