fix(nix): Resolve PATH mismatch for packages option in multi-user mode (#1691)

* fix(nix): Resolve PATH mismatch for packages option in multi-user mode

* fix(nix): align package installs with the active multi-user profile

Author: V-Subhankar-infy

src/nix/install.sh

@@ -113,10 +113,8 @@ fi
 chmod +x,o+r ${FEATURE_DIR} ${FEATURE_DIR}/post-install-steps.sh
 if [ "${MULTIUSER}" = "true" ]; then
     /usr/local/share/nix-entrypoint.sh
-    su ${USERNAME} -c "
-        . /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh
-        ${FEATURE_DIR}/post-install-steps.sh
-    "
+    . /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh
+    NIX_FEATURE_INSTALL_PROFILE=/nix/var/nix/profiles/default ${FEATURE_DIR}/post-install-steps.sh
 else
     su ${USERNAME} -c "
         . \$HOME/.nix-profile/etc/profile.d/nix.sh

src/nix/post-install-steps.sh

@@ -2,6 +2,14 @@
 set -e
 echo "(*) Executing post-installation steps..."
 
+# In multi-user mode, install into the default profile that is on PATH.
+NIX_ENV_PROFILE_ARGS=()
+NIX_PROFILE_INSTALL_ARGS=()
+if [ -n "${NIX_FEATURE_INSTALL_PROFILE}" ]; then
+  NIX_ENV_PROFILE_ARGS=(-p "${NIX_FEATURE_INSTALL_PROFILE}")
+  NIX_PROFILE_INSTALL_ARGS=(--profile "${NIX_FEATURE_INSTALL_PROFILE}")
+fi
+
 # if not starts with "nixpkgs." add it as prefix to package name
 add_nixpkgs_prefix() {
   local packages=$1
@@ -20,17 +28,17 @@ if [ ! -z "${PACKAGES}" ] && [ "${PACKAGES}" != "none" ]; then
   if [ "${USEATTRIBUTEPATH}" = "true" ]; then
     PACKAGES=$(add_nixpkgs_prefix "$PACKAGES")
     echo "Installing packages \"${PACKAGES}\" in profile..."
-    nix-env -iA ${PACKAGES}
+    nix-env "${NIX_ENV_PROFILE_ARGS[@]}" -iA ${PACKAGES}
   else
     echo "Installing packages \"${PACKAGES}\" in profile..."
-    nix-env --install ${PACKAGES}
+    nix-env "${NIX_ENV_PROFILE_ARGS[@]}" --install ${PACKAGES}
   fi
 fi
 
 # Install Nix flake in profile if specified
 if [ ! -z "${FLAKEURI}" ] && [ "${FLAKEURI}" != "none" ]; then
     echo "Installing flake ${FLAKEURI} in profile..."
-    nix profile install "${FLAKEURI}"
+  nix profile install "${NIX_PROFILE_INSTALL_ARGS[@]}" "${FLAKEURI}"
 fi
 
 nix-collect-garbage --delete-old

test/nix/packages.sh

@@ -29,6 +29,7 @@ check "nix-env" type nix-env
 check "vim_installed" type vim
 check "node_installed" type node
 check "yarn_installed" type yarn
+check "vim_in_default_profile" bash -lc "nix-env -p /nix/var/nix/profiles/default -q | grep -q '^vim'"
 
 # Report result
 # If any of the checks above exited with a non-zero exit code, the test will fail.

test/nix/scenarios.json

@@ -86,7 +86,7 @@
         "remoteUser": "vscode",
         "features": {
             "nix": {
-                "packages": "nodePackages.nodejs,nixpkgs.vim,nixpkgs.yarn",
+                "packages": "nodejs,nixpkgs.vim,nixpkgs.yarn",
                 "useAttributePath": true
             }
         }