Merge branch 'master' into staging

Conflicts (simple):
	pkgs/os-specific/linux/util-linux/default.nix

It seems this merge creates a new stdenv hash,
because we had changes on both branches :-/

lib/attrsets.nix

@@ -1,7 +1,7 @@
 # Operations on attribute sets.
 
 with {
-  inherit (builtins) head tail;
+  inherit (builtins) head tail length;
   inherit (import ./trivial.nix) or;
   inherit (import ./default.nix) fold;
   inherit (import ./strings.nix) concatStringsSep;

lib/customisation.nix

@@ -65,6 +65,13 @@ rec {
           overrideDerivation = fdrv:
             makeOverridable (args: overrideDerivation (f args) fdrv) origArgs;
         })
+      else if builtins.isFunction ff then
+        { override = newArgs:
+            makeOverridable f (origArgs // (if builtins.isFunction newArgs then newArgs origArgs else newArgs));
+          __functor = self: ff;
+          deepOverride = throw "deepOverride not yet supported for functors";
+          overrideDerivation = throw "overrideDerivation not yet supported for functors";
+        }
       else ff;
 
   deepOverrider = newArgs: name: x: if builtins.isAttrs x then (

lib/maintainers.nix

@@ -74,6 +74,7 @@
   garbas = "Rok Garbas <rok@garbas.si>";
   gavin = "Gavin Rogers <gavin@praxeology.co.uk>";
   goibhniu = "Cillian de Róiste <cillian.deroiste@gmail.com>";
+  gridaphobe = "Eric Seidel <eric@seidel.io>";
   guibert = "David Guibert <david.guibert@gmail.com>";
   henrytill = "Henry Till <henrytill@gmail.com>";
   hinton = "Tom Hinton <t@larkery.com>";

lib/modules.nix

@@ -356,6 +356,31 @@ rec {
   mkBefore = mkOrder 500;
   mkAfter = mkOrder 1500;
 
+  # Convenient property used to transfer all definitions and their
+  # properties from one option to another. This property is useful for
+  # renaming options, and also for including properties from another module
+  # system, including sub-modules.
+  #
+  #   { config, options, ... }:
+  #
+  #   {
+  #     # 'bar' might not always be defined in the current module-set.
+  #     config.foo.enable = mkAliasDefinitions (options.bar.enable or {});
+  #
+  #     # 'barbaz' has to be defined in the current module-set.
+  #     config.foobar.paths = mkAliasDefinitions options.barbaz.paths;
+  #   }
+  #
+  # Note, this is different than taking the value of the option and using it
+  # as a definition, as the new definition will not keep the mkOverride /
+  # mkDefault properties of the previous option.
+  #
+  mkAliasDefinitions = mkAliasAndWrapDefinitions id;
+  mkAliasAndWrapDefinitions = wrap: option:
+    mkMerge
+      (optional (isOption option && option.isDefined)
+        (wrap (mkMerge option.definitions)));
+
 
   /* Compatibility. */
   fixMergeModules = modules: args: evalModules { inherit modules args; check = false; };

lib/options.nix

@@ -96,6 +96,7 @@ rec {
           declarations = filter (x: x != unknownModule) opt.declarations;
           internal = opt.internal or false;
           visible = opt.visible or true;
+          type = opt.type.name or null;
         }
         // (if opt ? example then { example = scrubOptionValue opt.example; } else {})
         // (if opt ? default then { default = scrubOptionValue opt.default; } else {})