Remove the option ‘programs.bash.enable’

NixOS has a pervasive dependency on bash. For instance, the X11
session script sources /etc/profile to get a reasonable
environment. Thus we should not provide an option to disable bash.

Also, enabling zsh no longer sets ‘users.defaultUserShell’ to zsh, to
prevent a collision with bash's definition of the same
option. (Changing the default shell is also something that should be
left to the user.)

nixos/modules/programs/bash/bash.nix

@@ -40,6 +40,7 @@ in
 
     programs.bash = {
 
+      /*
       enable = mkOption {
         default = true;
         description = ''
@@ -52,6 +53,7 @@ in
         '';
         type = types.bool;
       };
+      */
 
       shellAliases = mkOption {
         default = config.environment.shellAliases // { which = "type -P"; };
@@ -114,7 +116,7 @@ in
 
   };
 
-  config = mkIf cfg.enable {
+  config = /* mkIf cfg.enable */ {
 
     programs.bash = {
 

nixos/modules/programs/zsh/zsh.nix

@@ -168,7 +168,7 @@ in
 
     environment.systemPackages = [ pkgs.zsh ];
 
-    users.defaultUserShell = mkDefault "/run/current-system/sw/bin/zsh";
+    #users.defaultUserShell = mkDefault "/run/current-system/sw/bin/zsh";
 
     environment.shells =
       [ "/run/current-system/sw/bin/zsh"

nixos/modules/rename.nix

@@ -128,5 +128,6 @@ in zipModules ([]
 # Options that are obsolete and have no replacement.
 ++ obsolete' [ "boot" "loader" "grub" "bootDevice" ]
 ++ obsolete' [ "boot" "initrd" "luks" "enable" ]
+++ obsolete' [ "programs" "bash" "enable" ]
 
 )