From 6f239d7309690153b181479735d9a254dfa2fcc3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20=C4=8Cun=C3=A1t?= <v@cunat.cz>
Date: Sun, 11 Jul 2021 16:02:17 +0200
Subject: [PATCH] Revert "setup.sh: fatal: This word should yield a string, but
 it contains an array"

This reverts commit bf99a819a16089a8df03cc06262f06b31dfb683c.
It caused regressions in some packages; see:
https://github.com/NixOS/nixpkgs/commit/bf99a819a160
---
 pkgs/stdenv/generic/setup.sh | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/pkgs/stdenv/generic/setup.sh b/pkgs/stdenv/generic/setup.sh
index 3515439337c6..4ae561fbca07 100644
--- a/pkgs/stdenv/generic/setup.sh
+++ b/pkgs/stdenv/generic/setup.sh
@@ -368,13 +368,16 @@ findInputs() {
     local var="${!varRef}"
     unset -v varVar varRef
 
-    # var is a reference to an array and can sometimes be undefined
-    # so checking the array with "${!var}[@]" does not work
-    # check if $pkgs is in the var ref array
-    # TODO(@Ericson2314): Restore using associative array
-    if [[ "${var}[*]" = *" $pkg "* ]]; then
-        return 0
-    fi
+    # TODO(@Ericson2314): Restore using associative array once Darwin
+    # nix-shell doesn't use impure bash. This should replace the O(n)
+    # case with an O(1) hash map lookup, assuming bash is implemented
+    # well :D.
+    local varSlice="${var}[*]"
+    # ${..-} to hack around old bash empty array problem
+    case "${!varSlice-}" in
+        *" $pkg "*) return 0 ;;
+    esac
+    unset -v varSlice
 
     eval "$var"'+=("$pkg")'