nix-shell: Fix bash completion

Nixpkgs's stdenv setup script sets the "nullglob" option, but doing so
breaks Bash completion on NixOS (when ‘programs.bash.enableCompletion’
is set) and on Ubuntu.  So clear that flag afterwards.  Of course,
this may break stdenv functions in subtle ways...

1 files changed, 1 insertions, 0 deletions

diff --git a/scripts/nix-build.in b/scripts/nix-build.in
index d7805f83c3f5..3b5b8413c823 100755
--- a/scripts/nix-build.in
+++ b/scripts/nix-build.in
@@ -210,6 +210,7 @@ foreach my $expr (@exprs) {
             'set +e; ' .
             'PS1="\n\[\033[1;32m\][nix-shell:\w]$\[\033[0m\] "; ' .
             'unset NIX_ENFORCE_PURITY; ' .
+            'shopt -u nullglob; ' .
             $envCommand);
         exec($ENV{NIX_BUILD_SHELL} // "bash", "--rcfile", $rcfile);
         die;