From 0bd2e2737cc9381cb83b273415e531c8cdc29981 Mon Sep 17 00:00:00 2001
From: Marien Zwart <marienz@google.com>
Date: Fri, 17 Oct 2025 20:57:15 +1100
Subject: [PATCH] emacsPackages.bpr: fix future preBuild

We conditionally set `preBuild` depending on version. For a new enough
version of the `bpr` package, we would set `preBuild` to the
`previousAttrs` attrset.

This looks like a copy/paste error, so fix it.

This code is currently not reachable: it would need a newer version of
`bpr`, which has had no changes upstream for several years.
---
 .../editors/emacs/elisp-packages/melpa-packages.nix             | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix b/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix
index 246786989209..982ff9759066 100644
--- a/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix
+++ b/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix
@@ -897,7 +897,7 @@ let
                     rm --verbose --force test-bpr.el
                   ''
                 else
-                  previousAttrs;
+                  previousAttrs.preBuild or "";
             }
           );