From 319ee04044740b9727f8d525fb769fa2b490837b Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Thu, 5 Jan 2023 01:15:50 +0100
Subject: [PATCH] easyOverlay: fix

The tests only caught this for the non-memoized system case.
---
 dev/tests/eval-tests.nix | 15 +++++++++++++--
 modules/perSystem.nix    |  2 +-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/dev/tests/eval-tests.nix b/dev/tests/eval-tests.nix
index c0e5d64..6db2fb0 100644
--- a/dev/tests/eval-tests.nix
+++ b/dev/tests/eval-tests.nix
@@ -35,7 +35,7 @@ rec {
     { inputs.self = { }; }
     {
       imports = [ flake-parts.flakeModules.easyOverlay ];
-      systems = [ "a" ];
+      systems = [ "a" "aarch64-linux" ];
       perSystem = { system, config, final, pkgs, ... }: {
         packages.default = config.packages.hello;
         packages.hello = pkg system "hello";
@@ -55,11 +55,19 @@ rec {
   };
 
   nixpkgsWithEasyOverlay = import nixpkgs {
+    # non-memoized
     system = "x86_64-linux";
     overlays = [ easyOverlay.overlays.default ];
     config = { };
   };
 
+  nixpkgsWithEasyOverlayMemoized = import nixpkgs {
+    # memoized
+    system = "aarch64-linux";
+    overlays = [ easyOverlay.overlays.default ];
+    config = { };
+  };
+
   runTests = ok:
 
     assert empty == {
@@ -90,9 +98,12 @@ rec {
     };
 
     # - exported package becomes part of overlay.
-    # - perSystem is invoked for the right system.
+    # - perSystem is invoked for the right system, when system is non-memoized
     assert nixpkgsWithEasyOverlay.hello == pkg "x86_64-linux" "hello";
 
+    # - perSystem is invoked for the right system, when system is memoized
+    assert nixpkgsWithEasyOverlayMemoized.hello == pkg "aarch64-linux" "hello";
+
     # - Non-exported package does not become part of overlay.
     assert nixpkgsWithEasyOverlay.default or null != pkg "x86_64-linux" "hello";
 
diff --git a/modules/perSystem.nix b/modules/perSystem.nix
index c46e3cf..7f3576c 100644
--- a/modules/perSystem.nix
+++ b/modules/perSystem.nix
@@ -115,7 +115,7 @@ in
     # performance cost has already been incurred, such as in `flakeModules.easyOverlay`,
     # where we run in the context of an overlay, and the performance cost of the
     # extra `pkgs` makes the cost of running `perSystem` probably negligible.
-    _module.args.getSystemIgnoreWarning = system: config.allSystems.${system} or config.perSystem system;
+    _module.args.getSystemIgnoreWarning = system: config.allSystems.${system} or (config.perSystem system);
   };
 
 }