This blog post has helped me clean up my postgres development environment on Mac. So making a copy!
How completely uninstall PostgreSQL 9.X on Mac OSX
This article is referenced from stackoverflow:
If installed PostgreSQL with homebrew , enter brew uninstall postgresql
If you used the EnterpriseDB installer , follow the following step.
Run the uninstaller on terminal window
sudo /Library/PostgreSQL/9.X/uninstall-postgresql.app/Contents/MacOS/installbuilder.sh
If installed with Postgres Installer, do:
open /Library/PostgreSQL/9.X/uninstall-postgresql.app
Remove the PostgreSQL and data folders. The Wizard will notify you that these were not removed.
sudo rm -rf /Library/PostgreSQL
Remove the ini file:
sudo rm /etc/postgres-reg.ini
Remove the PostgreSQL user using System Preferences -> Users & Groups.
Unlock the settings panel by clicking on the padlock and entering your password.
Select the PostgreSQL user and click on the minus button.
Restore your shared memory settings: sudo rm /etc/sysctl.conf
Note for macOS High Sierra
sudo rm /etc/sysctl.conf
--> error:/etc/sysctl.conf: No such file or directory