make default shell to zsh

Author: arctan95

.config/home-manager/home.nix

@@ -21,6 +21,23 @@
 
   home.sessionVariables = userConfig.env;
 
+  # Set zsh as default shell on activation
+  home.activation.make-zsh-default-shell = lib.hm.dag.entryAfter [ "writeBoundary" ] ''
+    # if zsh is not the current shell
+      PATH="/usr/bin:/bin:$PATH"
+      ZSH_PATH="/home/${user}/.nix-profile/bin/zsh"
+      if [[ $(getent passwd ${user}) != *"$ZSH_PATH" ]]; then
+        echo "setting zsh as default shell (using chsh). password might be necessary."
+        if grep -q $ZSH_PATH /etc/shells; then
+          echo "adding zsh to /etc/shells"
+          run echo "$ZSH_PATH" | sudo tee -a /etc/shells
+        fi
+        echo "running chsh to make zsh the default shell"
+        run chsh -s $ZSH_PATH ${user}
+        echo "zsh is now set as default shell !"
+      fi
+  '';
+
   # Let Home Manager install and manage itself.
   programs.home-manager.enable = true;