From 32ca59649b0af8d8d77905274fe63de3a3fc0d1e Mon Sep 17 00:00:00 2001
From: Jamie Quigley <jamie@quigley.xyz>
Date: Wed, 1 Feb 2023 20:43:26 +0000
Subject: [PATCH] nix-shell: Colour the prompt red if the user is root

This matches the nixos prompt colours - green for standard user, red for
root
---
 src/nix-build/nix-build.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/nix-build/nix-build.cc b/src/nix-build/nix-build.cc
index 049838bb1..da76c2ace 100644
--- a/src/nix-build/nix-build.cc
+++ b/src/nix-build/nix-build.cc
@@ -536,7 +536,9 @@ static void main_nix_build(int argc, char * * argv)
                 "SHELL=%5%; "
                 "BASH=%5%; "
                 "set +e; "
-                R"s([ -n "$PS1" -a -z "$NIX_SHELL_PRESERVE_PROMPT" ] && PS1='\n\[\033[1;32m\][nix-shell:\w]\$\[\033[0m\] '; )s"
+                R"s([ -n "$PS1" -a -z "$NIX_SHELL_PRESERVE_PROMPT" ] && )s" +
+                (getuid() == 0 ? R"s(PS1='\n\[\033[1;31m\][nix-shell:\w]\$\[\033[0m\] '; )s"
+                               : R"s(PS1='\n\[\033[1;32m\][nix-shell:\w]\$\[\033[0m\] '; )s") +
                 "if [ \"$(type -t runHook)\" = function ]; then runHook shellHook; fi; "
                 "unset NIX_ENFORCE_PURITY; "
                 "shopt -u nullglob; "