fix: ensures in-memory access token is updated when refresh token is used

src/Google/Client.php

@@ -169,6 +169,18 @@ public function __construct(array $config = array())
       $this->setScopes($this->config['scopes']);
       unset($this->config['scopes']);
     }
+
+    // Set a default token callback to update the in-memory access token
+    if (is_null($this->config['token_callback'])) {
+      $this->config['token_callback'] = function ($cacheKey, $newAccessToken) {
+        $this->setAccessToken(
+            [
+              'access_token' => $newAccessToken,
+              'created' => time(),
+            ]
+        );
+      };
+    }
   }
 
   /**

tests/Google/ClientTest.php

@@ -714,6 +714,36 @@ public function testTokenCallback()
     $this->assertTrue($called);
   }
 
+  public function testDefaultTokenCallback()
+  {
+    $this->onlyPhp55AndAbove();
+    $this->checkToken();
+
+    $client = $this->getClient();
+    $accessToken = $client->getAccessToken();
+
+    if (!isset($accessToken['refresh_token'])) {
+      $this->markTestSkipped('Refresh Token required');
+    }
+
+    // make the auth library think the token is expired
+    $accessToken['expires_in'] = 0;
+    $client->setAccessToken($accessToken);
+
+    // make a silly request to obtain a new token (it's ok if it fails)
+    $http = $client->authorize();
+    try {
+      $http->get('https://www.googleapis.com/books/v1/volumes?q=Voltaire');
+    } catch (Exception $e) {}
+
+    // Assert the in-memory token has been updated
+    $newToken = $client->getAccessToken();
+    $this->assertNotEquals(
+      $accessToken['access_token'],
+      $newToken['access_token']
+    );
+  }
+
   public function testExecuteWithFormat()
   {
     $this->onlyGuzzle6();