zsh-autosuggestions/alt-install

#!/bin/bash
# An alternative install script for zsh-autocomplete.
#
DESCRIPTION="this script adds/removes a   
.zsh-autosuggestionsrc reference to your .zshrc file."
ZSHRC=""
PATH_TO_RC="source $HOME/.zsh-autosuggestions/.zsh-autosuggestionsrc"

function usage()
{
        echo $0 : $DESCRIPTION
        echo "Usage"
        echo -e "\t" $0 " install   : attempts to install"
        echo -e "\t" $0 " uninstall : attempts to uninstall"
        exit 1
}

function install()
{

	# check if line exists in zshrc, add it if missing
	if grep -Fxq "$PATH_TO_RC" "$ZSHRC"
	then
		echo "currently installed, see $ZSHRC" 
	else
		echo "Backing up $ZSHRC to $ZSHRC.bak"
		cp "$ZSHRC" "$ZSHRC.bak"
		echo "Adding $PATH_TO_RC to $ZSHRC"
		echo "$PATH_TO_RC" >> "$ZSHRC"
	fi
}

function uninstall()
{
	# check if line exists in zshrc, remove if preset
	if grep -Fxq "$PATH_TO_RC" "$ZSHRC"
	then
		echo "Removing $PATH_TO_RC from $ZSHRC"
		grep -v "$PATH_TO_RC" "$ZSHRC" > "tmp-zsh-autosuggestion"
		cat "tmp-zsh-autosuggestion" > "$ZSHRC"
		rm "tmp-zsh-autosuggestion"
	else
		echo "not currently installed, see $ZSHRC"
	fi
}

function get_zhsrc()
{
	# attempt to find a .zshrc
	# check if it exists and writeable
	if [ -w "$HOME/.zshrc" ] ; then
		ZSHRC="$HOME/.zshrc"
	elif [ -w "$ZDOTDIR/.zshrc" ] ; then
		ZSHRC="$ZDOTDIR/.zshrc"
	else
		echo "Cannot find .zshrc "
		exit -1
	fi
}

function main()
{
	if [ "$1" == "install" ] ; then
		get_zhsrc
		install "$@"
	elif [ "$1" == "uninstall" ] ; then
		get_zhsrc
		uninstall "$@"
	else
		usage
	fi
}
main "$@" # $@ passes args to main.