ZSH is the default in OSX Catalina and later

[AlfredJKwack]

Apple will set the Zsh as the default for any new user account that is created in macOS Catalina or later.
As a consequence the OSX setup script is likely outdated since it's assuming bash as the shell environment.

[ranguard]

I'm happy to take pull request - but we need to support both old and new OSX's

[AlfredJKwack]

Fair enough @ranguard

As a starting point I would approach shell detection like the below.

if [ -n "`$SHELL -c 'echo $ZSH_VERSION'`" ]; then
   # assume Zsh
elif [ -n "`$SHELL -c 'echo $BASH_VERSION'`" ]; then
   # assume Bash
else
   # assume something else
fi

ZSH doesn't have to deal with notions such as .bashrc and .bash_profile. The ZSH loading order for both interactive login and non-login go through ~/.zshrc (see ref). That being said, perlbrew recommends using ~/.zshenv which also includes non-interactive shells so we can go with that. All of that to say that L39:L56 could be skipped entirely where ZSH is concerned

installing-perl/scripts/install_perl_on_osx.sh

Lines 39 to 56 in 7674a87

	echo -n "Checking for .bash_profile... "
	if [ -f $BASHP ]; then
	echo "FOUND"
	echo -n "Checking for .bashrc sourcing inside of .bash_profile... "
	if [ "" != "$( cat $BASHP | grep 'source ' | grep 'bashrc' )" ]; then
	echo "FOUND"
	else
	echo "NOT FOUND"
	echo "Adding 'source $BASHR' to $BASHP"
	echo "# Added by install_latest_perl_osx.pl" >>$BASHP
	echo "[ -r $BASHR ] && source $BASHR" >>$BASHP
	fi
	else
	echo "NOT FOUND"
	echo "Creating $BASHP"
	echo "# Added by install_latest_perl_osx.pl" >>$BASHP
	echo "[ -r $BASHR ] && source $BASHR" >>$BASHP
	fi

A refactoring of L76-L85 could accommodate both ZSH and BASH notions since the only variable is the file we're writing out to.

installing-perl/scripts/install_perl_on_osx.sh

Lines 76 to 85 in 7674a87

	echo "Checking/updating $BASHR to source perlbrew bashrc"
	if [ ! -f $BASHR ]; then
	# File missing so create
	echo "source $PBREW_BASHRC" >> $BASHR
	else
	if [ "" == "$( cat $BASHR | grep 'source ' | grep $PBREW_BASHRC )" ]; then
	# source line is missing - so add
	echo "source $PBREW_BASHRC" >> $BASHR
	fi;
	fi;

The last thing, and this is beyond the scope of this issue is the ARCHFLAGS. Since Apple decided to switch to its own silicon from Intel's I'm not sure whether it's worth adding a flag in support of 'uname -m' == 'arm64' or $(uname -p) == 'arm'. What's your take on that?

installing-perl/scripts/install_perl_on_osx.sh

Lines 70 to 74 in 7674a87

	# Build as i386 only
	arch=`uname -m`
	if [ "$arch" == 'i386' ]; then
	echo 'export ARCHFLAGS="-arch i386"' >> ~/perl5/perlbrew/etc/bashrc
	fi