Understanding how to use darwin-stubs

[cmacrae]

Hey @thefloweringash @LnL7 👋

I'm trying to update a package I maintain in nixpkgs that depends on a private framework; namely 'SkyLight'.
As far as I understand it, all private frameworks should be exposed in nixpkgs via darwin-stubs, however I get the following issue when trying to build:

clang src/manifest.m src/osax/sa_loader.c src/osax/sa_payload.c src/osax/sa_mach_bootstrap.c -std=c99 -Wall -g -O0 -fvisibility=hidden -mmacosx-version-min=10.13
 -F/System/Library/PrivateFrameworks -framework Carbon -framework Cocoa -framework CoreServices -framework SkyLight -framework ScriptingBridge -o bin/yabai
ld: framework not found SkyLight
clang-7: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [makefile:59: bin/yabai] Error 1
error: --- Error -------------------------------------------------------------------------------------------------------------------------------------- nix-build
builder for '/nix/store/vlxcmhavv0mhkw8z37zdikck8mmrlzv2-yabai-3.3.6.drv' failed with exit code 2; last 10 log lines:
  xxd -i -a ./src/osax/payload ./src/osax/sa_payload.c
  xxd -i -a ./src/osax/mach_bootstrap ./src/osax/sa_mach_bootstrap.c
  rm -f ./src/osax/loader
  rm -f ./src/osax/payload
  rm -f ./src/osax/mach_bootstrap
  mkdir -p ./bin
  clang src/manifest.m src/osax/sa_loader.c src/osax/sa_payload.c src/osax/sa_mach_bootstrap.c -std=c99 -Wall -g -O0 -fvisibility=hidden -mmacosx-version-min=10.
13 -F/System/Library/PrivateFrameworks -framework Carbon -framework Cocoa -framework CoreServices -framework SkyLight -framework ScriptingBridge -o bin/yabai
  ld: framework not found SkyLight
  clang-7: error: linker command failed with exit code 1 (use -v to see invocation)
  make: *** [makefile:59: bin/yabai] Error 1

Here's the diff of what I'm trying to do to expose this framework.
Is this the right approach? What am I missing here?

Thanks in advance for any help on this.

modified   pkgs/os-specific/darwin/apple-sdk/default.nix
@@ -284,6 +284,12 @@ in rec {
       setupHook = ./security-setup-hook.sh;
     });

+    SkyLight = stdenv.lib.overrideDerivation super.SkyLight (drv: {
+      __propagatedImpureHostDeps = drv.__propagatedImpureHostDeps ++ [
+        "/System/Library/PrivateFrameworks/"
+      ];
+    });
+
     QuartzCore = stdenv.lib.overrideDerivation super.QuartzCore (drv: {
       installPhase = drv.installPhase + ''
         f="$out/Library/Frameworks/QuartzCore.framework/Headers/CoreImage.h"

modified   pkgs/os-specific/darwin/apple-sdk/impure-deps.nix
@@ -75,6 +75,9 @@ rec {
     "/usr/lib/libxml2.2.dylib"
     "/usr/lib/libsqlite3.dylib"
   ];
+  SkyLight = [
+    "/System/Library/Frameworks/SkyLight.framework"
+  ];
   GSS = [
     "/System/Library/Frameworks/GSS.framework"
   ];

modified   pkgs/os-specific/darwin/yabai/default.nix
@@ -1,14 +1,14 @@
-{ stdenv, fetchFromGitHub, Carbon, Cocoa, ScriptingBridge, xxd }:
+{ stdenv, fetchFromGitHub, Carbon, Cocoa, ScriptingBridge, SkyLight, xxd }:

 stdenv.mkDerivation rec {
   pname = "yabai";
-  version = "3.3.4";
+  version = "3.3.6";

   src = fetchFromGitHub {
     owner = "koekeishiya";
     repo = pname;
     rev = "v${version}";
-    sha256 = "1pvyjdxgy7yxxz4x87f8an0dlxvxbnmv5kya8hkzw2na453ihvab";
+    sha256 = "0319k35c2rm0hsf0s5qdx4510g2n3nzg42cw1mhxcqrpi63604gg";
   };

   buildInputs = [ Carbon Cocoa ScriptingBridge xxd ];

modified   pkgs/top-level/all-packages.nix
@@ -28633,7 +28633,7 @@ in

   yabai = callPackage ../os-specific/darwin/yabai {
     inherit (darwin.apple_sdk.frameworks)
-      Carbon Cocoa ScriptingBridge;
+      Carbon Cocoa ScriptingBridge SkyLight;
   };

   yabause = libsForQt5.callPackage ../misc/emulators/yabause {

[thefloweringash]

It looks like there's a bug in the private frameworks. The symlinks are missing, and this prevents the linker from seeing them. Here's what I think it should be

diff --git a/pkgs/os-specific/darwin/apple-sdk/default.nix b/pkgs/os-specific/darwin/apple-sdk/default.nix
index 8a814e9558d..4df8e6226fb 100644
--- a/pkgs/os-specific/darwin/apple-sdk/default.nix
+++ b/pkgs/os-specific/darwin/apple-sdk/default.nix
@@ -192,6 +192,20 @@ let
       mkdir -p $out/Library/Frameworks/
       cp -r ${darwin-stubs}/System/Library/${lib.optionalString private "Private"}Frameworks/${name}.framework \
         $out/Library/Frameworks
+
+      cd $out/Library/Frameworks/${name}.framework
+
+      versions=(./Versions/*)
+      if [ "''${#versions[@]}" != 1 ]; then
+        echo "Unable to determine current version of framework ${name}"
+        exit 1
+      fi
+      current=$(basename ''${versions[0]})
+
+      chmod u+w -R .
+      ln -s "$current" Versions/Current
+      ln -s Versions/Current/* .
+
       # NOTE there's no re-export checking here, this is probably wrong
     '';
   };
@@ -300,7 +314,7 @@ in rec {
         "Versions/A/Frameworks/WebKitLegacy.framework/Versions/A/WebKitLegacy.tbd"
       ];
     });
-  } // lib.genAttrs [ "ContactsPersistence" "UIFoundation" "GameCenter" ] (x: tbdOnlyFramework x {});
+  } // lib.genAttrs [ "ContactsPersistence" "UIFoundation" "GameCenter" "SkyLight" ] (x: tbdOnlyFramework x {});

   bareFrameworks = lib.mapAttrs framework (import ./frameworks.nix {
     inherit frameworks libs;
diff --git a/pkgs/os-specific/darwin/yabai/default.nix b/pkgs/os-specific/darwin/yabai/default.nix
index b371e97d06f..9abc8d8b87b 100644
--- a/pkgs/os-specific/darwin/yabai/default.nix
+++ b/pkgs/os-specific/darwin/yabai/default.nix
@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchFromGitHub, Carbon, Cocoa, ScriptingBridge, xxd }:
+{ lib, stdenv, fetchFromGitHub, Carbon, Cocoa, SkyLight, ScriptingBridge, xxd }:

 stdenv.mkDerivation rec {
   pname = "yabai";
@@ -11,7 +11,7 @@ stdenv.mkDerivation rec {
     sha256 = "1pvyjdxgy7yxxz4x87f8an0dlxvxbnmv5kya8hkzw2na453ihvab";
   };

-  buildInputs = [ Carbon Cocoa ScriptingBridge xxd ];
+  buildInputs = [ Carbon Cocoa ScriptingBridge SkyLight xxd ];

   installPhase = ''
     mkdir -p $out/bin
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index bd86fed4cb2..2342d91bcd1 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -29353,7 +29353,7 @@ in

   yabai = callPackage ../os-specific/darwin/yabai {
     inherit (darwin.apple_sdk.frameworks)
-      Carbon Cocoa ScriptingBridge;
+      Carbon Cocoa ScriptingBridge SkyLight;
   };

   yabause = libsForQt5.callPackage ../misc/emulators/yabause {

Unfortunately this isn't enough to link, since it seems to require symbols that are newer than macOS 10.12:

clang src/manifest.m src/osax/sa_loader.c src/osax/sa_payload.c src/osax/sa_mach_bootstrap.c -std=c99 -Wall -g -O0 -fvisibility=hidden -mmacosx-version-min=10.13 -F/System/Library/PrivateFrameworks -framework Carbon -framework Cocoa -framework CoreServices -framework SkyLight -framework ScriptingBridge -o bin/yabai
Undefined symbols for architecture x86_64:
  "_SLSWindowIteratorAdvance", referenced from:
      _window_tags in manifest-064ed7.o
      _window_manager_set_window_layer in manifest-064ed7.o
  "_SLSWindowIteratorGetParentID", referenced from:
      _window_manager_set_window_layer in manifest-064ed7.o
  "_SLSWindowIteratorGetTags", referenced from:
      _window_tags in manifest-064ed7.o
  "_SLSWindowIteratorGetWindowID", referenced from:
      _window_manager_set_window_layer in manifest-064ed7.o
  "_SLSWindowQueryResultCopyWindows", referenced from:
      _window_tags in manifest-064ed7.o
      _window_manager_set_window_layer in manifest-064ed7.o
  "_SLSWindowQueryWindows", referenced from:
      _window_tags in manifest-064ed7.o
      _window_manager_set_window_layer in manifest-064ed7.o
ld: symbol(s) not found for architecture x86_64

[cmacrae]

Ah, sorry, I should've closed this back when you replied!
Thank you very much for the thorough response - much appreciated. I also see you've approved my associated nixpkgs PR, so thanks for that too! 🙏