feat: use zshenv over zshrc in setup

[gautamprikshit1]

Closes #1537

@chriskrycho

[chriskrycho]

🎉 Thank you!

[chriskrycho]

So what we have here is good, and we will also need to update the install.sh.in script, which only checks for .zshrc to identify the current shell:

volta/dev/unix/install.sh.in

Lines 118 to 156 in aace0e5

	case "$(basename "/$SHELL")" in
	bash)
	# Shells on macOS default to opening with a login shell, while Linuxes
	# default to a *non*-login shell, so if this is macOS we look for
	# `.bash_profile` first; if it's Linux, we look for `.bashrc` first. The
	# `*` fallthrough covers more than just Linux: it's everything that is not
	# macOS (Darwin). It can be made narrower later if need be.
	case $(uname) in
	Darwin)
	echo_fexists "$HOME/.bash_profile" || echo_fexists "$HOME/.bashrc"
	;;
	*)
	echo_fexists "$HOME/.bashrc" || echo_fexists "$HOME/.bash_profile"
	;;
	esac
	;;
	zsh)
	echo "$HOME/.zshrc"
	;;
	fish)
	echo "$HOME/.config/fish/config.fish"
	;;
	*)
	# Fall back to checking for profile file existence. Once again, the order
	# differs between macOS and everything else.
	local profiles
	case $(uname) in
	Darwin)
	profiles=( .profile .bash_profile .bashrc .zshrc .config/fish/config.fish )
	;;
	*)
	profiles=( .profile .bashrc .bash_profile .zshrc .config/fish/config.fish )
	;;
	esac
	for profile in "${profiles[@]}"; do
	echo_fexists "$HOME/$profile" && break
	done
	;;

If you can knock that out as well, we can get this merged!

[chriskrycho]

Excellent! Much obliged!