From 904b8c5ec026dd0b24cfd7a9c08bd4e41a3c7313 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Na=C3=AFm=20Camille=20Favier?= <n@monade.li>
Date: Sun, 25 Jan 2026 22:36:18 +0100
Subject: [PATCH] Set `inNixShell`

`nix-shell` passes a `inNixShell = true` argument when evaluating a
file, so we should replicate this behaviour. There is another mechanism
for signaling that we are in a nix shell, namely the `IN_NIX_SHELL`
environment variable (which both nix-shell and nix-direnv also set),
but this is by nature not a good solution since it leaks into e.g.
further `nix-build` invocations in nix shells.

This only concerns non-flake setups, of course.
---
 direnvrc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/direnvrc b/direnvrc
index 6f6eac88..a6c3ae20 100644
--- a/direnvrc
+++ b/direnvrc
@@ -525,7 +525,7 @@ use_nix() {
       if [[ -n $packages ]]; then
         extra_args+=("--expr" "with import <nixpkgs> {}; mkShell { buildInputs = [ $packages ]; }")
       else
-        extra_args+=("--file" "$nixfile")
+        extra_args+=("--file" "$nixfile" --arg inNixShell true)
         if [[ -n $attribute ]]; then
           extra_args+=("$attribute")
         fi