From 2c4410f1d744fc2b891e805fe94dcd6531ea75ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Agust=C3=ADn=20Covarrubias?= <agustin@agucova.dev>
Date: Fri, 12 Dec 2025 17:48:18 -0300
Subject: [PATCH] test: add shebangs to shell.nix test scripts

  Fix intermittent SIGSEGV (exit code 139) on macOS when running
  nix-shell and shebang tests inside the nix sandbox.

  The foo, bar, and ruby test scripts were created without shebangs,
  which causes intermittent crashes when executed via command
  substitution on macOS. Adding proper shebangs resolves the flakiness.

  Potentially closes: #13106

(cherry picked from commit 7b3d7eb6343f33a14a9ec55be909f806ff6c49ab)
---
 tests/functional/shell.nix | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/tests/functional/shell.nix b/tests/functional/shell.nix
index 5e9f48818..fb10ebc1d 100644
--- a/tests/functional/shell.nix
+++ b/tests/functional/shell.nix
@@ -96,14 +96,16 @@ let
 
     foo = runCommand "foo" { } ''
       mkdir -p $out/bin
-      echo 'echo ${fooContents}' > $out/bin/foo
+      echo '#!${shell}' > $out/bin/foo
+      echo 'echo ${fooContents}' >> $out/bin/foo
       chmod a+rx $out/bin/foo
       ln -s ${shell} $out/bin/bash
     '';
 
     bar = runCommand "bar" { } ''
       mkdir -p $out/bin
-      echo 'echo bar' > $out/bin/bar
+      echo '#!${shell}' > $out/bin/bar
+      echo 'echo bar' >> $out/bin/bar
       chmod a+rx $out/bin/bar
     '';
 
@@ -116,7 +118,8 @@ let
     # ruby "interpreter" that outputs "$@"
     ruby = runCommand "ruby" { } ''
       mkdir -p $out/bin
-      echo 'printf %s "$*"' > $out/bin/ruby
+      echo '#!${shell}' > $out/bin/ruby
+      echo 'printf %s "$*"' >> $out/bin/ruby
       chmod a+rx $out/bin/ruby
     '';