エラー内容
could not connect to server: Connection refused Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5432? could not connect to server: Connection refused Is the server running on host "localhost" (127.0.0.1) and accepting TCP/IP connections on port 5432?
$ brew uninstall postgresql
$ rm -rf /usr/local/var/postgres/
$ brew install postgresql
もちろん、ローカルのpostgreデータ吹っ飛ぶので注意。