我的新mac到了，哈哈，有点喜悦。
准备从svn上将公司的项目checkout到我的mac上，
升级Mac OS 10.15.4
安装Xcode 11.4
打开终端，输入：
svn --version(查看svn版本)
svn:error:Failed to locale 'svn'
svn:error:The subversion command line tools are no longer provided by Xcode.
我还以为新系统、Xcode不在支持svn 了呢/
原来Xcode安装，是默认不安装命令行工具的，需要自己手动安装一下。
终端输入：
xcode-select --install
安装完成，就可以使用svn了。
>>$ svn --version
svn, version 1.10.4 (r1850624)
compiled Dec 13 2019, 19:47:45 on x86_64-apple-darwin18.0.0
Copyright (C) 2019 The Apache Software Foundation.
This software consists of contributions made by many people;
see the NOTICE file for more information.
Subversion is open source software, see http://subversion.apache.org/
The following repository access (RA) modules are available:
* ra_svn : Module for accessing a repository using the svn network protocol.
- with Cyrus SASL authentication
- handles 'svn' scheme
* ra_local : Module for accessing a repository on local disk.
- handles 'file' scheme
* ra_serf : Module for accessing a repository via WebDAV protocol using serf.
- using serf 1.3.9 (compiled with 1.3.9)
- handles 'http' scheme
- handles 'https' scheme
The following authentication credential caches are available:
* Plaintext cache in /Users/lidj/.subversion
* GPG-Agent
* Mac OS X Keychain
