Merge pull request #11346 from mjgallag/nix-profile-daemon-set-u

nix-daemon.sh profile script: operate under `set -u` in bash

scripts/nix-profile-daemon.sh.in

@@ -52,7 +52,7 @@ elif [ -e /etc/pki/tls/certs/ca-bundle.crt ]; then # Fedora, CentOS
 else
   # Fall back to what is in the nix profiles, favouring whatever is defined last.
   check_nix_profiles() {
-    if [ -n "$ZSH_VERSION" ]; then
+    if [ -n "${ZSH_VERSION:-}" ]; then
       # Zsh by default doesn't split words in unquoted parameter expansion.
       # Set local_options for these options to be reverted at the end of the function
       # and shwordsplit to force splitting words in $NIX_PROFILES below.

tests/installer/default.nix

@@ -217,10 +217,16 @@ let
         $ssh <<EOF
           set -ex
 
+          # enable nounset while loading the profile
+          # this may or may not work on all distros, depending on the quality of their scripts
+          set -u
+
           # FIXME: get rid of this; ideally ssh should just work.
           source ~/.bash_profile || true
           source ~/.bash_login || true
           source ~/.profile || true
+          set +u
+
           source /etc/bashrc || true
 
           nix-env --version