behat/composer error

[helmo]

In the latest provision test I noticed the error below. Still the test passed.

  - Installing drupal/drupal-extension (v3.2.2)

    Downloading: Connecting...    Downloading: 15%    Downloading: 100%

symfony/event-dispatcher suggests installing symfony/http-kernel ()

symfony/dependency-injection suggests installing symfony/expression-language (For using expressions in service container configuration)

symfony/dependency-injection suggests installing symfony/proxy-manager-bridge (Generate service proxies to lazy load them)

behat/mink suggests installing behat/mink-zombie-driver (fast and JS-enabled headless driver for any app (requires node.js))

symfony/translation suggests installing psr/log (To use logging capability in translator)

symfony/console suggests installing psr/log (For using the console logger)

symfony/class-loader suggests installing symfony/polyfill-apcu (For using ApcClassLoader on HHVM)

behat/behat suggests installing behat/symfony2-extension (for integration with Symfony2 web framework)

behat/behat suggests installing behat/yii-extension (for integration with Yii web framework)



  [ErrorException]                                                             

  file_put_contents(./composer.lock): failed to open stream: Permission denie  

  d                                                                            



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