原因：闲来无事想学习flutter进行开发，于是就下载VSCode，但是在配置Dart环境时出现了问题
1.Homebrew的问题
在输入rudy时终端提示找不到命令，紧接着提示
-bash: rudy: command not found 找不到命令
ERROR: Error installing redis:
The last version of redis (>= 0) to support your Ruby & RubyGems was 4.1.1. Try installing it with `gem install redis -v 4.1.1`
（“支持Ruby&RubyGems的最新版本redis（>=0）是4.1.1。试着用'gem install redis-v4.1.1安装它`”）
redis requires Ruby version >= 2.3.0. The current ruby version is 2.2.0.
此处是是已经给出了提示使用gem install redis-v4.1.1进行安装，主要原因就是redis版本太低，需要升级，提示的错误中已经给出了操作步骤，以后遇到此情况需谨记
2.brew的安装问题，比较复杂，同样是找不到命令行
brew: command not found
先是修改了/.bash_profile文件，vi ~/.bash_profile打开文件，添加了一句
export PATH=/usr/local/bin:$PATH
export HOMEBREW_NO_AUTO_UPDATE=true
之后，source .bash_profile，之后输入 brew命令之后看到了brew的信息
屏幕快照 2020-07-15 15.57.35.png
3.之后就是更新问题
虽然中间还有其他问题，不过问度娘之后基本都可解决
brew的更新，需要换镜像，如果不换镜像的话会卡住，度娘上有很多源，本人换的是阿里的源
# 替换成阿里巴巴的 brew.git 仓库地址:
cd "$(brew --repo)"
git remote set-url origin https://mirrors.aliyun.com/homebrew/brew.git
# 替换成阿里巴巴的 homebrew-core.git 仓库地址:
cd "$(brew --repo)/Library/Taps/homebrew/homebrew-core"
git remote set-url origin https://mirrors.aliyun.com/homebrew/homebrew-core.git
之后还需要修改/.bash_profile中的URL
echo 'export HOMEBREW_BOTTLE_DOMAIN=https://mirrors.aliyun.com/homebrew/homebrew-bottles' >> ~/.bash_profile
之后source .bash_profile
紧接着brew update，走起
屏幕快照 2020-07-15 13.59.58.png
屏幕快照 2020-07-15 14.00.15.png
屏幕快照 2020-07-15 14.00.53.png
此处已经可以看到brew的版本好，之后brew的命令行生效了
4.dart的问题
以为学习flutter就是直接使用flutter就可以了，但是dart是flutter的基础，就像OC是swift的基础一样，不能不学，所以也需要安装dart的环境
传送门：https://dart.dev/get-dart
安装dart有两种方式，我一开始是使用的就是使用工具安装，就是通过brew进行安装，但是
屏幕快照 2020-07-15 14.01.09.png
屏幕快照 2020-07-15 14.01.40.png
无法成功的下载软件包，甚至通过git改了代理仍然不行，
尝试通过手动下载，获取目录
$ brew --cache
/Users/shockerli/Library/Caches/Homebrew
把刚下载好的软件包拷贝到这个目录下:
$ cp ~/Downloads/dartsdk-macos-x64-release.zip /Users/shockerli/Library/Caches/Homebrew/
重新执行安装命令
brew install dart
一般人，到这里就已经安装成功了，但是很可惜仍然抱错
之后通过命令行，打印详细的日志
brew install dart -v
brew install dart -v
==> Installing dart from dart-lang/dart
/usr/bin/sandbox-exec -f /private/tmp/homebrew20190810-60798-mlb2s.sb nice /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby -W0 -I /usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/simplecov-cobertura-1.3.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/ruby-macho-2.2.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rubocop-rspec-1.35.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rubocop-performance-1.4.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rubocop-0.74.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/unicode-display_width-1.6.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/ruby-progressbar-1.10.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-wait-0.0.9/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-retry-0.6.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-its-1.3.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-3.8.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-mocks-3.8.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-expectations-3.8.4/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-core-3.8.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rspec-support-3.8.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/ronn-0.7.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rdiscount-2.2.0.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/extensions/universal-darwin-18/2.3.0/rdiscount-2.2.0.1:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/rainbow-3.0.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/plist-3.5.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/parser-2.6.3.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/parallel_tests-2.29.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/parallel-1.17.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/mustache-1.1.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/mechanize-2.7.6/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/webrobots-0.1.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/ntlm-http-0.1.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/nokogiri-1.10.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/extensions/universal-darwin-18/2.3.0/nokogiri-1.10.3:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/mini_portile2-2.4.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/net-http-persistent-3.1.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/net-http-digest_auth-1.4.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/mime-types-3.2.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/mime-types-data-3.2019.0331/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/jaro_winkler-1.5.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/extensions/universal-darwin-18/2.3.0/jaro_winkler-1.5.3:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/http-cookie-1.0.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/hpricot-0.8.6/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/extensions/universal-darwin-18/2.3.0/hpricot-0.8.6:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/domain_name-0.5.20190701/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/unf-0.1.4/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/unf_ext-0.0.7.6/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/extensions/universal-darwin-18/2.3.0/unf_ext-0.0.7.6:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/diff-lcs-1.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/coveralls-0.8.23/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/thor-0.20.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/term-ansicolor-1.7.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/tins-1.21.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/simplecov-0.16.1/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/simplecov-html-0.10.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/docile-1.3.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/json-2.2.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/extensions/universal-darwin-18/2.3.0/json-2.2.0:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/connection_pool-2.2.2/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/backports-3.15.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/ast-2.4.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/activesupport-5.2.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/tzinfo-1.2.5/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/thread_safe-0.3.6/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/minitest-5.11.3/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/i18n-1.6.0/lib:/usr/local/Homebrew/Library/Homebrew/vendor/bundle/bundler/../ruby/2.3.0/gems/concurrent-ruby-1.1.5/lib:/Library/Ruby/Site/2.3.0:/Library/Ruby/Site/2.3.0/x86_64-darwin18:/Library/Ruby/Site/2.3.0/universal-darwin18:/Library/Ruby/Site:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/vendor_ruby/2.3.0:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/vendor_ruby/2.3.0/x86_64-darwin18:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/vendor_ruby/2.3.0/universal-darwin18:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/vendor_ruby:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/2.3.0:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/2.3.0/x86_64-darwin18:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/2.3.0/universal-darwin18:/usr/local/Homebrew/Library/Homebrew -- /usr/local/Homebrew/Library/Homebrew/build.rb /usr/local/Homebrew/Library/Taps/dart-lang/homebrew-dart/dart.rb --verbose
==> Downloading https://storage.googleapis.com/dart-archive/channels/stable/release/2.4.1/sdk/dartsdk-macos-x64-release.zip
/usr/bin/curl -q --show-error --user-agent Homebrew/2.1.9-21-g625a780\ \(Macintosh\;\ Intel\ Mac\ OS\ X\ 10.14.2\)\ curl/7.54.0 --fail --location --remote-time --continue-at 0 --output /Users/shockerli/Library/Caches/Homebrew/downloads/4d2412a5d84521393e0e1ecdce0662569e13c2c47762093a760939fa9dd4a917--dartsdk-macos-x64-release.zip.incomplete https://storage.googleapis.com/dart-archive/channels/stable/release/2.4.1/sdk/dartsdk-macos-x64-release.zip
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- 0:00:43 --:--:-- 0
curl: (56) LibreSSL SSL_read: SSL_ERROR_SYSCALL, errno 60
Error: An exception occurred within a child process:
DownloadError: Failed to download resource "dart"
Download failed: https://storage.googleapis.com/dart-archive/channels/stable/release/2.4.1/sdk/dartsdk-macos-x64-release.zip
发现了homedart 下载时的缓存地址
/Users/shockerli/Library/Caches/Homebrew/downloads/4d2412a5d84521393e0e1ecdce0662569e13c2c47762093a760939fa9dd4a917--dartsdk-macos-x64-release.zip.incomplete
XXX.incomplete 表示下载未完成，但这是 Homebrew 期望的下载文件路径。
那我们就将下载的软件包拷贝到这个路径，并去除 .incomplete:
mv ~/Downloads/dartsdk-macos-x64-release.zip /Users/shockerli/Library/Caches/Homebrew/downloads/4d2412a5d84521393e0e1ecdce0662569e13c2c47762093a760939fa9dd4a917--dartsdk-macos-x64-release.zip
之后再brew install dart -v，原以为进行到这里就可以了，但是最近的运气一直不是很好，还是报错，此路不通，没有办法，一般人到这里之后就会放弃的，但是一想起自己那无处安放的魅力之后，毅然决然的继续进行下去，整理了一下思路，既然此路不通的话，就往回找，开头提到了安装dart有两种方式，一种是通过homebrew工具安装，一种是通过手动下载dartSDK安装，主要目的就是dart的SDK，那直接下载dart的SDK不就行了，之后在度娘上找到了dart的SDK
版本虽然是2.4.0的，最新的版本是2.8.0的吗但是能用就行了，下载之后，在source文件中改一下路径就行了，之后运行VScode和终端发现，
屏幕快照 2020-07-15 16.33.00.png
屏幕快照 2020-07-15 16.33.11.png
问题解决了
补充：在修改source文件时，修改路径之后 source ~/.bash_profile报错，（将源文件的名称给改了，出现了）
-bash: /Users/xxx/.profile: No such file or directory
这是将源文件的抬头改了，只需要改回source ~/.profile就可以了
屏幕快照 2020-07-15 16.38.07.png
或者：
将source ~/.profile 删除，然后在第一行编辑加入：
export PATH=/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin
这是系统默认初始环境变量，直接复制粘贴就行
最后退出保存，重新打开终端问题解决。