From c5b890c4139f854329caa6232c02fe2a592f3847 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fabian=20M=C3=B6ller?= <fabianm88@gmail.com>
Date: Fri, 31 Jan 2025 08:29:56 +0100
Subject: [PATCH] patch-shebangs: fix `env -S` with only one argument
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In case `patchShebangs` encounters an `env -S` interpreter with only one
argument following, it would duplicate that argument and most likely invalidate
the resulting interpreter line.

Reproducer:

```nix
(import <nixpkgs> {}).writeTextFile {
  name = "patch-shebangs-env-s";
  text = ''
    #!/bin/env -S bash
  '';
  executable = true;
  checkPhase = ''
    patchShebangs $out
  '';
}
```

The resulting file would contain

```
#!/nix/store/pw…fk-coreutils-9.5/bin/env -S /nix/store/4f…g60-bash-5.2p37/bin/bash bash
```

instead of the correct

```
#!/nix/store/pw…fk-coreutils-9.5/bin/env -S /nix/store/4f…g60-bash-5.2p37/bin/bash
```
---
 pkgs/build-support/setup-hooks/patch-shebangs.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/build-support/setup-hooks/patch-shebangs.sh b/pkgs/build-support/setup-hooks/patch-shebangs.sh
index f22da254a791..a7b2b110f23f 100644
--- a/pkgs/build-support/setup-hooks/patch-shebangs.sh
+++ b/pkgs/build-support/setup-hooks/patch-shebangs.sh
@@ -89,7 +89,7 @@ patchShebangs() {
         if [[ "$oldPath" == *"/bin/env" ]]; then
             if [[ $arg0 == "-S" ]]; then
                 arg0=${args%% *}
-                args=${args#* }
+                [[ "$args" == *" "* ]] && args=${args#* } || args=
                 newPath="$(PATH="${!pathName}" type -P "env" || true)"
                 args="-S $(PATH="${!pathName}" type -P "$arg0" || true) $args"