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.

.github/workflows/ci.yml

@@ -195,20 +195,6 @@ jobs:
       - uses: DeterminateSystems/magic-nix-cache-action@main
       - run: nix build -L .#hydraJobs.tests.githubFlakes .#hydraJobs.tests.tarballFlakes .#hydraJobs.tests.functional_user
 
-  meson_build:
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [ubuntu-latest, macos-latest]
-    runs-on: ${{ matrix.os }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: DeterminateSystems/nix-installer-action@main
-      - uses: DeterminateSystems/magic-nix-cache-action@main
-      # Only meson packages that don't have a tests.run derivation.
-      # Those that have it are already built and tested as part of nix flake check.
-      - run: nix build -L .#hydraJobs.build.{nix-cmd,nix-main}.$(nix-instantiate --eval --expr builtins.currentSystem | sed -e 's/"//g')
-
   flake_regressions:
     needs: vm_tests
     runs-on: ubuntu-22.04

flake.nix

@@ -139,11 +139,6 @@
 
           nix = final.nixComponents.nix;
 
-          nix_noTests = final.nix.override {
-            doInstallCheck = false;
-            doCheck = false;
-          };
-
           # See https://github.com/NixOS/nixpkgs/pull/214409
           # Remove when fixed in this flake's nixpkgs
           pre-commit =
@@ -222,20 +217,49 @@
           # 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;
         }
         # We need to flatten recursive attribute sets of derivations to pass `flake check`.
         // flatMapAttrs
           { # Components we'll iterate over in the upcoming lambda
             "nix" = { };
-            # Temporarily disabled because GitHub Actions OOM issues. Once
-            # the old build system is gone and we are back to one build
-            # system, we should reenable these.
-            #"nix-util" = { };
-            #"nix-store" = { };
-            #"nix-fetchers" = { };
+            "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" = { };
+            "nix-ng" = { };
           }
           (pkgName: {}: {
               # These attributes go right into `packages.<system>`.

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 +1,91 @@
+{
+  lib,
+  stdenv,
+  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-internal-api-docs
+    nix-external-api-docs
+
+  ] ++ lib.optionals (stdenv.buildPlatform.canExecute stdenv.hostPlatform) [
+    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
+
+    nix-functional-tests
+  ];
+})

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
 {
@@ -85,7 +86,7 @@ in
     self.packages.${system}.nix.override { enableGC = false; }
   );
 
-  buildNoTests = forAllSystems (system: nixpkgsFor.${system}.native.nix_noTests);
+  buildNoTests = forAllSystems (system: nixpkgsFor.${system}.native.nixComponents.nix-cli);
 
   # Toggles some settings for better coverage. Windows needs these
   # library combinations, and Debian build Nix with GNU readline too.

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 = {

tests/nixos/quick-build.nix

@@ -27,13 +27,13 @@ in
   };
 
   config = {
-    passthru.quickBuild = 
+    passthru.quickBuild =
       let withQuickBuild = extendModules { modules = [{ quickBuild = true; }]; };
       in withQuickBuild.config.test;
 
     defaults = { pkgs, ... }: {
       config = lib.mkIf test.config.quickBuild {
-        nix.package = pkgs.nix_noTests;
+        nix.package = pkgs.nixComponents.nix-cli;
 
         system.forbiddenDependenciesRegexes = [
           # This would indicate that the quickBuild feature is broken.
@@ -44,4 +44,4 @@ in
       };
     };
   };
-}
+}