nix: don't allow overriding the import packages. This causes overlays to fail

default.nix

@@ -1,195 +1,196 b''
 # Nix environment for the community edition
 #
 # This shall be as lean as possible, just producing the rhodecode-vcsserver
 # derivation. For advanced tweaks to pimp up the development environment we use
 # "shell.nix" so that it does not have to clutter this file.
 
 args@
 { pythonPackages ? "python27Packages"
 , pythonExternalOverrides ? self: super: {}
 , doCheck ? false
 , ...
 }:
 
-let pkgs_ = (import <nixpkgs> {}); in
+let
+  pkgs_ = (import <nixpkgs> {});
+in
 
 let
-
-  pkgs = args.pkgs or (import <nixpkgs> {
+  pkgs = import <nixpkgs> {
     overlays = [
       (import ./pkgs/overlays.nix)
     ];
     inherit
       (pkgs_)
       system;
-  });
+  };
 
   # Works with the new python-packages, still can fallback to the old
   # variant.
   basePythonPackagesUnfix = basePythonPackages.__unfix__ or (
     self: basePythonPackages.override (a: { inherit self; }));
 
   # Evaluates to the last segment of a file system path.
   basename = path: with pkgs.lib; last (splitString "/" path);
 
   # source code filter used as arugment to builtins.filterSource.
   src-filter = path: type: with pkgs.lib;
     let
       ext = last (splitString "." path);
     in
       !builtins.elem (basename path) [
         ".git" ".hg" "__pycache__" ".eggs" ".idea" ".dev"
-        "bower_components" "node_modules"
+        "node_modules" "node_binaries"
         "build" "data" "result" "tmp"] &&
       !builtins.elem ext ["egg-info" "pyc"] &&
       # TODO: johbo: This check is wrong, since "path" contains an absolute path,
       # it would still be good to restore it since we want to ignore "result-*".
       !hasPrefix "result" path;
 
   sources =
     let
       inherit
         (pkgs.lib)
         all
         isString
         attrValues;
       sourcesConfig = pkgs.config.rc.sources or {};
     in
       # Ensure that sources are configured as strings. Using a path
       # would result in a copy into the nix store.
       assert all isString (attrValues sourcesConfig);
       sourcesConfig;
 
   version = builtins.readFile "${rhodecode-vcsserver-src}/vcsserver/VERSION";
   rhodecode-vcsserver-src = builtins.filterSource src-filter ./.;
 
   pythonLocalOverrides = self: super: {
     rhodecode-vcsserver =
       let
         releaseName = "RhodeCodeVCSServer-${version}";
       in super.rhodecode-vcsserver.override (attrs: {
       inherit
         doCheck
         version;
 
       name = "rhodecode-vcsserver-${version}";
       releaseName = releaseName;
       src = rhodecode-vcsserver-src;
       dontStrip = true; # prevent strip, we don't need it.
 
       # expose following attributed outside
       passthru = {
         pythonPackages = self;
       };
 
       propagatedBuildInputs =
         attrs.propagatedBuildInputs or [] ++ [
         pkgs.git
         pkgs.subversion
       ];
 
       # set some default locale env variables
       LC_ALL = "en_US.UTF-8";
       LOCALE_ARCHIVE =
         if pkgs.stdenv.isLinux
         then "${pkgs.glibcLocales}/lib/locale/locale-archive"
         else "";
 
       # Add bin directory to path so that tests can find 'vcsserver'.
       preCheck = ''
         export PATH="$out/bin:$PATH"
       '';
 
       # custom check phase for testing
       checkPhase = ''
         runHook preCheck
         PYTHONHASHSEED=random py.test -vv -p no:sugar -r xw --cov-config=.coveragerc --cov=vcsserver --cov-report=term-missing vcsserver
         runHook postCheck
       '';
 
       postCheck = ''
         echo "Cleanup of vcsserver/tests"
         rm -rf $out/lib/${self.python.libPrefix}/site-packages/vcsserver/tests
       '';
 
       postInstall = ''
         echo "Writing vcsserver meta information for rccontrol to nix-support/rccontrol"
         mkdir -p $out/nix-support/rccontrol
         cp -v vcsserver/VERSION $out/nix-support/rccontrol/version
         echo "DONE: vcsserver meta information for rccontrol written"
 
         mkdir -p $out/etc
         cp configs/production.ini $out/etc
         echo "DONE: saved vcsserver production.ini into $out/etc"
 
         # python based programs need to be wrapped
         mkdir -p $out/bin
         ln -s ${self.python}/bin/python $out/bin/
         ln -s ${self.gunicorn}/bin/gunicorn $out/bin/
         ln -s ${self.pyramid}/bin/prequest $out/bin/
         ln -s ${self.pyramid}/bin/pserve $out/bin/
 
         # Symlink version control utilities
         # We ensure that always the correct version is available as a symlink.
         # So that users calling them via the profile path will always use the
         # correct version. Wrapping is required so those can "import"
         # vcsserver python hooks.
 
         ln -s ${pkgs.git}/bin/git $out/bin
         ln -s ${self.mercurial}/bin/hg $out/bin
         ln -s ${pkgs.subversion}/bin/svn* $out/bin
 
         echo "DONE: created symlinks into $out/bin"
         DEPS="$out/bin/*"
 
         # wrap only dependency scripts, they require to have full PYTHONPATH set
         # to be able to import all packages
         for file in $DEPS;
         do
           wrapProgram $file \
             --prefix PATH : $PATH \
             --prefix PYTHONPATH : $PYTHONPATH \
             --set PYTHONHASHSEED random
         done
 
         echo "DONE: vcsserver binary wrapping"
 
       '';
 
     });
   };
 
   basePythonPackages = with builtins;
     if isAttrs pythonPackages then
       pythonPackages
     else
       getAttr pythonPackages pkgs;
 
   pythonGeneratedPackages = import ./pkgs/python-packages.nix {
     inherit
       pkgs;
     inherit
       (pkgs)
       fetchurl
       fetchgit
       fetchhg;
   };
 
   pythonVCSServerOverrides = import ./pkgs/python-packages-overrides.nix {
     inherit
       pkgs
       basePythonPackages;
   };
 
 
   # Apply all overrides and fix the final package set
   myPythonPackagesUnfix = with pkgs.lib;
     (extends pythonExternalOverrides
     (extends pythonLocalOverrides
     (extends pythonVCSServerOverrides
     (extends pythonGeneratedPackages
              basePythonPackagesUnfix))));
 
   myPythonPackages = (pkgs.lib.fix myPythonPackagesUnfix);
 
 in myPythonPackages.rhodecode-vcsserver

release.nix

@@ -1,16 +1,14 b''
 # This file defines how to "build" for packaging.
 
-{ pkgs ? import <nixpkgs> {}
-, doCheck ? true
+{ doCheck ? true
 }:
 
 let
   vcsserver = import ./default.nix {
     inherit
-      doCheck
-      pkgs;
+      doCheck;
   };
 
 in {
   build = vcsserver;
 }