properly test no sudo/run as root

Author: jhheider

.github/workflows/ci.yml

@@ -135,9 +135,10 @@ jobs:
 
   sudo-not-required:
       runs-on: ubuntu-latest
+      container: debian:buster-slim
       steps:
         - uses: actions/checkout@v3
-        - run: sudo apt-get remove sudo
+        - run: apt-get update && apt-get --yes install curl
         - run: ./install.sh
 
   sudo-required:

install.sh

@@ -283,9 +283,10 @@ check_path() {
 	then
 		echo  #spacer
 
-		# Shellcheck thinks `>/dev/null` was supposed to be `-gt /dev/null` here. For some reason.
-		# shellcheck disable=2065
-		if test -w /usr/local/bin -o ! -e /usr/local/bin -a mkdir -p /usr/local/bin >/dev/null 2>&1
+		# NOTE: Binary -a and -o are inherently ambiguous.  Use 'test EXPR1
+    #   && test EXPR2' or 'test EXPR1 || test EXPR2' instead.
+		# https://man7.org/linux/man-pages/man1/test.1.html
+		if test -w /usr/local/bin || (test ! -e /usr/local/bin && mkdir -p /usr/local/bin >/dev/null 2>&1)
 		then
 			mkdir -p /usr/local/bin
 			ln -sf "$tea" /usr/local/bin/tea