From 247d5623795d85938b41be1571c83c2e5d189fcd Mon Sep 17 00:00:00 2001
From: Wolfgang Walther <walther@technowledgy.de>
Date: Tue, 10 Jun 2025 13:17:00 +0200
Subject: [PATCH] ci/nixpkgs-vet: add badFiles and conflictingPaths checks

Those checks are part of top-level/nixpkgs-basic-release-checks.nix, but
can be run in CI already to prevent regressions. The idea is to upstream
them into nixpkgs-vet eventually, but we can just as well run them as-is
in the same derivation already.
---
 ci/nixpkgs-vet.nix | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/ci/nixpkgs-vet.nix b/ci/nixpkgs-vet.nix
index ccc5ba289dcf5..58b5024589bd0 100644
--- a/ci/nixpkgs-vet.nix
+++ b/ci/nixpkgs-vet.nix
@@ -29,5 +29,25 @@ runCommand "nixpkgs-vet"
 
     nixpkgs-vet --base ${filtered base} ${filtered head}
 
+    # TODO: Upstream into nixpkgs-vet, see:
+    # https://github.com/NixOS/nixpkgs-vet/issues/164
+    badFiles=$(find ${filtered head}/pkgs -type f -name '*.nix' -print | xargs grep -l '^[^#]*<nixpkgs/' || true)
+    if [[ -n $badFiles ]]; then
+      echo "Nixpkgs is not allowed to use <nixpkgs> to refer to itself."
+      echo "The offending files:"
+      echo "$badFiles"
+      exit 1
+    fi
+
+    # TODO: Upstream into nixpkgs-vet, see:
+    # https://github.com/NixOS/nixpkgs-vet/issues/166
+    conflictingPaths=$(find ${filtered head} | awk '{ print $1 " " tolower($1) }' | sort -k2 | uniq -D -f 1 | cut -d ' ' -f 1)
+    if [[ -n $conflictingPaths ]]; then
+      echo "Files in nixpkgs must not vary only by case."
+      echo "The offending paths:"
+      echo "$conflictingPaths"
+      exit 1
+    fi
+
     touch $out
   ''