From 716cb6f1ef32742ecfc1d05831a1b8aadceb0316 Mon Sep 17 00:00:00 2001
From: Taylor Buchanan <me+dev.git@taylorbuchanan.com>
Date: Tue, 16 Jun 2026 13:46:39 -0500
Subject: [PATCH] Resolve sh from PATH for generated stub scripts

_shunit_mktempFunc writes its stub scripts (including the noexec
exec-permission probe) with a hardcoded #!/bin/sh. On systems without
/bin/sh the stubs cannot exec, so the noexec probe fails and shUnit2
aborts with a misleading "declare TMPDIR ... exec permission" error
even when TMPDIR is executable. This affects non-FHS layouts such as
NixOS (#185) and Termux (where sh lives under $PREFIX/bin).

Resolve sh from PATH via `command -v sh`. Unlike #!/usr/bin/env sh it
does not assume /usr/bin/env exists either, and on FHS systems it
still resolves to /bin/sh, so behavior is unchanged there.

Refs #185.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Taylor Buchanan <me+dev.git@taylorbuchanan.com>
---
 shunit2 | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/shunit2 b/shunit2
index 7cb5a57..2207609 100755
--- a/shunit2
+++ b/shunit2
@@ -1119,17 +1119,20 @@ _shunit_mktempDir() {
 # Args:
 #   None
 _shunit_mktempFunc() {
+  # Not every system provides /bin/sh, so resolve sh from PATH rather than
+  # hardcoding the stub interpreter.
+  _shunit_sh_=`command -v sh`
   for _shunit_func_ in oneTimeSetUp oneTimeTearDown setUp tearDown suite noexec
   do
     _shunit_file_="${__shunit_tmpDir}/${_shunit_func_}"
     command cat <<EOF >"${_shunit_file_}"
-#! /bin/sh
+#!${_shunit_sh_}
 exit ${SHUNIT_TRUE}
 EOF
     command chmod +x "${_shunit_file_}"
   done
 
-  unset _shunit_file_
+  unset _shunit_file_ _shunit_sh_
 }
 
 # Final cleanup function to leave things as we found them.