From fb14e20249fd58facfc4819fa9fac4d75db1893f Mon Sep 17 00:00:00 2001
From: Pacman99 <pachum99@gmail.com>
Date: Fri, 26 Mar 2021 14:41:10 -0700
Subject: [PATCH] lib/filterPackages: filter by flake requirements returns only
 non-broken derivations that support the system.

---
 lib/attrs.nix   | 9 +++++++++
 lib/default.nix | 3 ++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/attrs.nix b/lib/attrs.nix
index 534a9918..dbc44b5f 100644
--- a/lib/attrs.nix
+++ b/lib/attrs.nix
@@ -26,4 +26,13 @@ rec {
     });
 
   concatAttrs = lib.fold (attr: sum: lib.recursiveUpdate sum attr) { };
+
+  # Filter out packages that support given system and follow flake check requirements
+  filterPackages = system: packages:
+    let
+      # Everything that nix flake check requires for the packages output
+      filter = (n: v: with v; let platforms = meta.hydraPlatforms or meta.platforms or [ ]; in
+        lib.isDerivation v && !meta.broken && builtins.elem system platforms);
+    in
+      lib.filterAttrs filter packages;
 }
diff --git a/lib/default.nix b/lib/default.nix
index 7fceb3ce..2ff31023 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -17,7 +17,8 @@ lib.makeExtensible (final:
     lists = callLibs ./lists.nix;
     strings = callLibs ./strings.nix;
 
-    inherit (attrs) mapFilterAttrs genAttrs' pathsToImportedAttrs concatAttrs;
+    inherit (attrs) mapFilterAttrs genAttrs'
+      pathsToImportedAttrs concatAttrs filterPackages;
     inherit (lists) pathsIn;
     inherit (strings) rgxToString;
   })