xbps-src: remove default python_version

Closes: #21209 [via git-merge-pr]

common/environment/setup/python.sh

@@ -2,9 +2,6 @@
 # Useful variables for determining Python version and paths.
 #
 
-# set version 2 as the default Python
-python_version="2"
-
 py2_ver="2.7"
 py2_lib="/usr/lib/python${py2_ver}"
 py2_sitelib="${py2_lib}/site-packages"

common/hooks/pre-pkg/03-rewrite-python-shebang.sh

@@ -4,25 +4,23 @@
 hook() {
 	local pyver= shebang= off=
 
-	: ${pyver:=2}
-
 	if [ -d ${PKGDESTDIR}/usr/lib/python* ]; then
 		pyver="$(find ${PKGDESTDIR}/usr/lib/python* -prune -type d | grep -o '[[:digit:]]\.[[:digit:]]$')"
 	fi
 
-	if [ -n "$pycompile_version" ]; then
-		pyver="$pycompile_version"
-	fi
-
-	if [ "$python_version" = "3" ]; then
+	if [ -n "$python_version" ]; then
 		pyver="$python_version"
 	fi
 
-	shebang="#!/usr/bin/python${pyver%.*}"
+	if [ -n "$pyver" ]; then
+		shebang="#!/usr/bin/python${pyver%.*}"
+	fi
+
 	find "${PKGDESTDIR}" -type f -print0 | \
 		while IFS= read -r -d '' file; do
 			[ ! -s "$file" ] && continue
 			[ -z "$(sed -n -E -e 2q -e '/^#!.*([[:space:]]|\/)python([0-9]\.[0-9])?([[:space:]]+|$)/p' "$file")" ] && continue
+			[ -n "$shebang" ] || msg_error "cannot convert shebang, set python_version\n"
 			echo "   Shebang converted to '$shebang': ${file#$PKGDESTDIR}"
 			sed -i "1s@.*python.*@${shebang}@" -- "$file"
 		done