Make wrapper derivation

This ensures just `nix build`-ing the flake doesn't forget to run all
tests. One can still specifiy specific attributes to just build one
thing.

flake.nix

@@ -222,7 +222,7 @@
           # for which we don't apply the full build matrix such as cross or static.
           inherit (nixpkgsFor.${system}.native)
             changelog-d;
-          default = self.packages.${system}.nix;
+          default = self.packages.${system}.nix-ng;
           nix-internal-api-docs = nixpkgsFor.${system}.native.nixComponents.nix-internal-api-docs;
           nix-external-api-docs = nixpkgsFor.${system}.native.nixComponents.nix-external-api-docs;
         }

packaging/components.nix

@@ -56,13 +56,15 @@ in
 
   nix-cmd = callPackage ../src/libcmd/package.nix { };
 
-  # Will replace `nix` once the old build system is gone.
-  nix-ng = callPackage ../src/nix/package.nix { version = fineVersion; };
+  nix-cli = callPackage ../src/nix/package.nix { version = fineVersion; };
 
   nix-functional-tests = callPackage ../src/nix-functional-tests/package.nix { version = fineVersion; };
 
   nix-internal-api-docs = callPackage ../src/internal-api-docs/package.nix { version = fineVersion; };
   nix-external-api-docs = callPackage ../src/external-api-docs/package.nix { version = fineVersion; };
 
   nix-perl-bindings = callPackage ../src/perl/package.nix { };
+
+  # Will replace `nix` once the old build system is gone.
+  nix-ng = callPackage ../packaging/everything.nix { };
 }

packaging/everything.nix

@@ -0,0 +1,88 @@
+{
+  buildEnv,
+
+  nix-util,
+  nix-util-c,
+  nix-util-test-support,
+  nix-util-tests,
+
+  nix-store,
+  nix-store-c,
+  nix-store-test-support,
+  nix-store-tests,
+
+  nix-fetchers,
+  nix-fetchers-tests,
+
+  nix-expr,
+  nix-expr-c,
+  nix-expr-test-support,
+  nix-expr-tests,
+
+  nix-flake,
+  nix-flake-tests,
+
+  nix-main,
+  nix-main-c,
+
+  nix-cmd,
+
+  nix-cli,
+
+  nix-functional-tests,
+
+  nix-internal-api-docs,
+  nix-external-api-docs,
+
+  nix-perl-bindings,
+}:
+
+(buildEnv rec {
+  name = "nix-${nix-cli.version}";
+  paths = [
+    nix-util
+    nix-util-c
+    nix-util-test-support
+    nix-util-tests
+
+    nix-store
+    nix-store-c
+    nix-store-test-support
+    nix-store-tests
+
+    nix-fetchers
+    nix-fetchers-tests
+
+    nix-expr
+    nix-expr-c
+    nix-expr-test-support
+    nix-expr-tests
+
+    nix-flake
+    nix-flake-tests
+
+    nix-main
+    nix-main-c
+
+    nix-cmd
+
+    nix-cli
+
+    nix-functional-tests
+
+    nix-internal-api-docs
+    nix-external-api-docs
+
+    nix-perl-bindings
+  ];
+}).overrideAttrs (_: {
+  doCheck = true;
+
+  checkInputs = [
+    # Actually run the unit tests too
+    nix-util-tests.tests.run
+    nix-store-tests.tests.run
+    nix-expr-tests.tests.run
+    nix-flake-tests.tests.run
+  ];
+})

packaging/hydra.nix

@@ -61,8 +61,9 @@ let
     "nix-main"
     "nix-main-c"
     "nix-cmd"
-    "nix-ng"
+    "nix-cli"
     "nix-functional-tests"
+    "nix-ng"
   ];
 in
 {

tests/functional/package.nix

@@ -15,7 +15,7 @@
 
 , nix-store
 , nix-expr
-, nix-ng
+, nix-cli
 
 , rapidcheck
 , gtest
@@ -67,7 +67,7 @@ mkMesonDerivation (finalAttrs: {
   ];
 
   nativeBuildInputs = finalAttrs.passthru.baseNativeBuildInputs ++ [
-    nix-ng
+    nix-cli
   ];
 
   buildInputs = [
@@ -105,7 +105,7 @@ mkMesonDerivation (finalAttrs: {
   doCheck = true;
 
   installPhase = ''
-    touch $out
+    mkdir $out
   '';
 
   meta = {