Atom Uninstall
No, the Atom text editor does not have an uninstaller. On Mac OS X, to completely uninstall, remove the following files and directories:
~/.atom
/usr/local/bin/atom (NB only present if command line tools installed)
/usr/local/bin/apm (NB only present if command line tools installed)
/Applications/Atom.app
~/Library/Application Support/com.apple.sharedfilelist/com.apple.LSSharedFileList.ApplicationRecentDocuments/com.github.atom.sfl
~/Library/Preferences/com.github.atom.plist
~/Library/Application Support/com.github.atom.ShipIt
~/Library/Application Support/Atom
~/Library/Caches/com.github.atom.ShipIt/
~/Library/Saved Application State/com.github.atom.savedState
~/Library/Logs/Atom/
~/Library/Preferences/com.github.atom.helper.plist
~/Library/Preferences/com.github.atom.LSSharedFileList.plist
~/Library/Preferences/ByHost/com.github.atom.ShipIt.<letters/numbers>.plist
~/Library/Saved Application State/com.github.atom.savedState
NB: The <letter/numbers> in the file name located in ~/Library/Preferences/ByHost appear to be a unique string per machine.