Brew는 Mac에 PHP와 확장 기능을 설치합니다.

$ brew untap homebrew/tap

$ brew install php@7.0

# 查看pecl
$ pecl version
PEAR Version: 1.10.5
PHP Version: 7.0.30
Zend Engine Version: 3.0.0
Running on: Darwin Mac 17.5.0 Darwin Kernel Version 17.5.0: Mon Mar  5 22:24:32 PST 2018; root:xnu-4570.51.1~1/RELEASE_X86_64 x86_64
# 安装xdebug扩展
$ pecl install xdebug
...
...
Build process completed successfully
Installing '/usr/local/Cellar/php@7.0/7.0.30/pecl/20151012/xdebug.so'
install ok: channel://pecl.php.net/xdebug-2.6.0
Extension xdebug enabled in php.ini

# xdebug.so编译到了 /usr/local/Cellar/php@7.0/7.0.30/pecl/20151012/ 目录下
$ cd /usr/local/Cellar/php@7.0/7.0.30 && ll
total 256
...
lrwxr-xr-x   1 username  admin    23B  5  7 19:53 pecl -> /usr/local/lib/php/pecl
...
# `/usr/local/Cellar/php@7.0/7.0.30/pecl` 目录实际上软链到 `/usr/local/lib/php/pecl` 目录下
# 将xdebug.so移动到php@7.0默认扩展目录
# php@7.0默认扩展目录为`/usr/local/Cellar/php@7.0/7.0.30/lib/php/20151012/`,可通过phpinfo()获取
$ cp /usr/local/Cellar/php@7.0/7.0.30/pecl/20151012/xdebug.so /usr/local/Cellar/php@7.0/7.0.30/lib/php/20151012/

# 查看php.ini目录
$ php --ini
....
Loaded Configuration File:         /usr/local/etc/php/7.0/php.ini
Scan for additional .ini files in: /usr/local/etc/php/7.0/conf.d
....
# 编辑php.ini
$ vim /usr/local/etc/php/7.0/php.ini
# 删除第一行:  zend_extension="xdebug.so" 
# 在`/usr/local/etc/php/7.0/conf.d`目录下新增xdebug.ini
$ vim /usr/local/etc/php/7.0/conf.d/xdebug.ini
# 加入以下内容
[xdebug]
zend_extension="xdebug.so"

$ php -m
[PHP Modules]
...
...
[Zend Modules]
Xdebug               <== 成功安装
Zend OPcache