darwin: add darwin-aliases.nix

pkgs/top-level/darwin-aliases.nix

@@ -0,0 +1,50 @@
+lib: self: super: pkgs:
+
+### Deprecated aliases - for backward compatibility
+
+### Please maintain this list in ASCIIbetical ordering.
+### Hint: the "sections" are delimited by ### <letter> ###
+
+# These aliases should not be used within nixpkgs, but exist to improve
+# backward compatibility in projects outside of nixpkgs. See the
+# documentation for the `allowAliases` option for more background.
+
+# A script to convert old aliases to throws and remove old
+# throws can be found in './maintainers/scripts/remove-old-aliases.py'.
+
+# Add 'preserve, reason: reason why' after the date if the alias should not be removed.
+# Try to keep them to a minimum.
+# valid examples of what to preserve:
+#   distro aliases such as:
+#     debian-package-name -> nixos-package-name
+
+# pkgs is provided to allow packages to be moved out of the darwin attrset.
+
+with self;
+
+let
+  # Removing recurseForDerivation prevents derivations of aliased attribute set
+  # to appear while listing all the packages available.
+  removeRecurseForDerivations =
+    alias:
+    if alias.recurseForDerivations or false then
+      lib.removeAttrs alias [ "recurseForDerivations" ]
+    else
+      alias;
+
+  # Disabling distribution prevents top-level aliases for non-recursed package
+  # sets from building on Hydra.
+  removeDistribute = alias: if lib.isDerivation alias then lib.dontDistribute alias else alias;
+
+  # Make sure that we are not shadowing something from darwin-packages.nix.
+  checkInPkgs =
+    n: alias:
+    if builtins.hasAttr n super then throw "Alias ${n} is still in darwin-packages.nix" else alias;
+
+  mapAliases = lib.mapAttrs (
+    n: alias: removeDistribute (removeRecurseForDerivations (checkInPkgs n alias))
+  );
+in
+
+mapAliases ({
+})

pkgs/top-level/darwin-packages.nix

@@ -18,12 +18,14 @@ let
   fetchurlBoot = import ../build-support/fetchurl/boot.nix {
     inherit (stdenv) system;
   };
+
+  aliases = self: super: lib.optionalAttrs config.allowAliases (import ../top-level/darwin-aliases.nix lib self super pkgs);
 in
 
 makeScopeWithSplicing' {
   otherSplices = generateSplicesForMkScope "darwin";
   extra = spliced: spliced.apple_sdk.frameworks;
-  f = (self: let
+  f = lib.extends aliases (self: let
   inherit (self) mkDerivation callPackage;
 
   # Must use pkgs.callPackage to avoid infinite recursion.