卸載重裝watchman
1.brew uninstall --force watchman
2.rm -rf /usr/local/var/run/watchman/
3.brew install watchman
==> Installing watchman
==> Downloading https://homebrew.bintray.com/bottles/watchman-4.9.0.high_sierra. ######################################################################## 100.0% ==> Pouring watchman-4.9.0.high_sierra.bottle.tar.gz
==> launchctl unload -F /Users/xxxxxxx/Library/LaunchAgents/com.github.facebook.w ??? /usr/local/Cellar/watchman/4.9.0: 23 files, 2MB<成功>