Composer 2.0预览版现已发布:https://github.com/composer/composer/releases 修正了我的问题。你可以用composer self-update来设置预览

编辑:Composer 2与内存调优发布

在Windows xampp我只是改变:

;memory_limit=512M 

在php.ini中:

memory_limit =-1

然后通过xampp重新启动Apache

结果如下:

; Maximum amount of memory a script may consume
; http://php.net/memory-limit
memory_limit =-1
;memory_limit=512M

Fatal error: Allowed memory size of 1610612736 bytes exhausted (tried to allocate 4096 bytes) in phar:///usr/local/bin/composer/src/Composer/DependencyResolver/RuleWatchGraph.php on line 52 Check https://getcomposer.org/doc/articles/troubleshooting.md#memory-limit-errors for more info on how to handle out of memory errors.

Set memory_limit to -1 works for me;) (vim /etc/php/7.2/cli/php.ini)

由于之前的答案都不包括set，所以我花了一点时间来弄清楚如何在Windows中做到这一点而不改变php.ini，但下面是对我有效的方法:

set COMPOSER_MEMORY_LIMIT=-1
composer require hwi/oauth-bundle php-http/guzzle6-adapter php-http/httplug-bundle

要获取当前的memory_limit值，运行:

php -r "echo ini_get('memory_limit').PHP_EOL;"

尝试增加php.ini文件中的限制(例如/etc/php5/cli/php.ini对于debian类系统):

; Use -1 for unlimited or define an explicit value like 2G
memory_limit = -1

或者，你可以用命令行参数增加限制:

php -d memory_limit=-1 composer.phar require hwi/oauth-bundle php-http/guzzle6-adapter php-http/httplug-bundle

要加载php.ini文件，请尝试:

php --ini

另一个快速解决方案:

php composer.phar COMPOSER_MEMORY_LIMIT=-1 require hwi/oauth-bundle php-http/guzzle6-adapter php-http/httplug-bundle

或者是:

COMPOSER_MEMORY_LIMIT=-1 composer require hwi/oauth-bundle php-http/guzzle6-adapter php-http/httplug-bundle

对我来说，这适用于共享托管。

COMPOSER_MEMORY_LIMIT=-1 composer update