我有macOS High Sierra 10.13.3，我发现最近使用Homebrew来安装一些工具导致问题。任何安装都会导致显示如下：
$ brew install ethereum
Error: No available formula with the name "ethereum"
==> Searching for a previously deleted formula (in the last month)...
Error: No previously deleted formula found.
==> Searching for similarly named formulae...
==> Searching local taps...
Error: No similarly named formulae found.
==> Searching taps...
==> Searching taps on GitHub...
This formula was found in a tap:
caskroom/cask/ethereum-wallet
To install it, run:
brew install caskroom/cask/ethereum-wallet
之前我成功使用brew安装，但在升级操作系统后，问题首先出现。如果我运行“brew doctor”，它会显示：
Warning: "config" scripts exist outside your system or Homebrew directories.
`./configure` scripts often look for *-config scripts to determine if
software packages are installed, and what additional flags to use when
compiling and linking.
Having additional scripts in your path can confuse software installed via
Homebrew if the config script overrides a system or Homebrew provided
script of the same name. We found the following "config" scripts:
/opt/local/bin/ncursesw6-config
/opt/local/bin/pcre-config
/opt/local/bin/ncurses6-config
Warning: You have MacPorts or Fink installed:
/opt/local/bin/port
This can cause trouble. You don't have to uninstall them, but you may want to
temporarily move them out of the way, e.g.
sudo mv /opt/local ~/macports