Fix getDirty check for dates, fixes mongodb#373

src/Jenssegers/Mongodb/Model.php

@@ -355,6 +355,29 @@ public function attributesToArray()
         return $attributes;
     }
 
+    /**
+     * Determine if the new and old values for a given key are numerically equivalent.
+     *
+     * @param  string  $key
+     * @return bool
+     */
+    protected function originalIsNumericallyEquivalent($key)
+    {
+        $current = $this->attributes[$key];
+
+        $original = $this->original[$key];
+
+        // Date comparison.
+        if (in_array($key, $this->getDates()))
+        {
+            $current = $current instanceof MongoDate ? $this->asDateTime($current) : $current;
+            $original = $original instanceof MongoDate ? $this->asDateTime($original) : $original;
+            return $current == $original;
+        }
+
+        return parent::originalIsNumericallyEquivalent($key);
+    }
+
     /**
      * Remove one or more fields.
      *

tests/ModelTest.php

@@ -490,4 +490,14 @@ public function testDotNotation()
         $this->assertEquals('Paris', $user->{'address.city'});
     }
 
+    public function testGetDirtyDates()
+    {
+        $user = new User();
+        $user->setRawAttributes(['name' => 'John Doe', 'birthday' => new DateTime('19 august 1989')], true);
+        $this->assertEmpty($user->getDirty());
+
+        $user->birthday = new DateTime('19 august 1989');
+        $this->assertEmpty($user->getDirty());
+    }
+
 }