Merge pull request #2 from equip/feature/diffable-entity-trait

Add DiffableEntityTrait

Author: elazar

src/Traits/DiffableEntityTrait.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace Equip\Data\Traits;
+
+/**
+ * Intended to be used by classes implementing Equip\Data\EntityInterface that
+ * also need to implement Equip\Data\DiffableInterface.
+ */
+trait DiffableEntityTrait /* implements DiffableInterface */
+{
+    /**
+     * @see \Equip\Data\EntityInterface::withData()
+     *
+     * @param array $data
+     *
+     * @return static
+     */
+    abstract public function withData(array $data);
+
+    /**
+     * @see \Equip\Data\ArraySerializableInterface::toArray()
+     *
+     * @return array
+     */
+    abstract public function toArray();
+
+    /**
+     * @param array $values
+     *
+     * @return array
+     */
+    public function diff(array $values)
+    {
+        $copy = $this->withData($values);
+        return array_diff_assoc($copy->toArray(), $this->toArray());
+    }
+}