Unit test for IndexInfo's ArrayAccess implementation

tests/Model/IndexInfoTest.php

@@ -97,6 +97,20 @@ class IndexInfoTest extends TestCase
         $this->assertSame($expectedInfo, $info->__debugInfo());
     }
 
+    public function testImplementsArrayAccess()
+    {
+        $info = new IndexInfo([
+            'v' => 1,
+            'key' => ['x' => 1],
+            'name' => 'x_1',
+            'ns' => 'foo.bar',
+        ]);
+
+        $this->assertInstanceOf('ArrayAccess', $info);
+        $this->assertTrue(isset($info['name']));
+        $this->assertSame('x_1', $info['name']);
+    }
+
     /**
      * @expectedException MongoDB\Exception\BadMethodCallException
      * @expectedExceptionMessage MongoDB\Model\IndexInfo is immutable