Laravel Composer安装一直处于失败状态

I'm trying to install Laravel 5.2 using Composer on Windows but it keeps on failing.

C:\wamp\www>composer create-project --prefer-dist laravel/laravel vas
You are running composer with xdebug enabled. This has a major impact on runtime performance. See https://getcomposer.org/xdebug
Installing laravel/laravel (v5.2.24)
  - Installing laravel/laravel (v5.2.24)
    Downloading: 100%

Created project in vas
> php -r "copy('.env.example', '.env');"
Script php -r "copy('.env.example', '.env');" handling the post-root-package-install event returned with an error


  [RuntimeException]
  Error Output:


create-project [-s|--stability STABILITY] [--prefer-source] [--prefer-dist] [--repository REPOSITORY] [--repository-url REPOSITORY-URL] [--dev] [--no-dev] [--no-plugins] [--no-custom-installers] [--no-scripts] [--no-progress] [--keep-vcs] [--no-install] [--ignore-platform-reqs] [--] [<package>] [<directory>] [<version>]

It looks like it's failing on php -r - try running this command manually and see if you get the same error? if you do, it's something to do with your PHP CLI.