ruff: Build as a standalone without Python

Using `buildPythonPackage` make `ruff` propagate the Python used for the build, which might not be the same Python as you want in your development shell.

#350654 changed the ruff top-level attribute to be built with Python modules.
This doesn't actually make much sense, we have versioned Python sets, and including just the one Python in the top-level package isn't helpful, and causes issues downstream related to PATH & PYTHONPATH.

See my related [uv PR](#357113 (comment)).

pkgs/by-name/ru/ruff-lsp/package.nix

@@ -36,7 +36,7 @@ python3Packages.buildPythonApplication rec {
     pytestCheckHook
     pytest-asyncio
     python-lsp-jsonrpc
-    ruff.bin
+    ruff
     versionCheckHook
   ];
   versionCheckProgramArg = [ "--version" ];

pkgs/by-name/ru/ruff/package.nix

@@ -4,7 +4,6 @@
   fetchFromGitHub,
   installShellFiles,
   stdenv,
-  python3Packages,
   darwin,
   rust-jemalloc-sys,
   ruff-lsp,
@@ -14,15 +13,9 @@
   nixosTests,
 }:
 
-python3Packages.buildPythonPackage rec {
+rustPlatform.buildRustPackage rec {
   pname = "ruff";
   version = "0.8.0";
-  pyproject = true;
-
-  outputs = [
-    "bin"
-    "out"
-  ];
 
   src = fetchFromGitHub {
     owner = "astral-sh";
@@ -39,18 +32,10 @@ python3Packages.buildPythonPackage rec {
         'return "${placeholder "bin"}/bin/ruff"'
   '';
 
-  cargoDeps = rustPlatform.fetchCargoVendor {
-    inherit pname version src;
-    hash = "sha256-O5+uVYWtSMEj7hBrc/FUuqRBN4hUlEbtDPF42kpL7PA=";
-  };
+  useFetchCargoVendor = true;
+  cargoHash = "sha256-O5+uVYWtSMEj7hBrc/FUuqRBN4hUlEbtDPF42kpL7PA=";
 
-  nativeBuildInputs =
-    [ installShellFiles ]
-    ++ (with rustPlatform; [
-      cargoSetupHook
-      maturinBuildHook
-      cargoCheckHook
-    ]);
+  nativeBuildInputs = [ installShellFiles ];
 
   buildInputs =
     [
@@ -61,18 +46,12 @@ python3Packages.buildPythonPackage rec {
       libiconv
     ];
 
-  postInstall =
-    ''
-      mkdir -p $bin/bin
-      mv $out/bin/ruff $bin/bin/
-      rmdir $out/bin
-    ''
-    + lib.optionalString (stdenv.buildPlatform.canExecute stdenv.hostPlatform) ''
-      installShellCompletion --cmd ruff \
-        --bash <($bin/bin/ruff generate-shell-completion bash) \
-        --fish <($bin/bin/ruff generate-shell-completion fish) \
-        --zsh <($bin/bin/ruff generate-shell-completion zsh)
-    '';
+  postInstall = lib.optionalString (stdenv.buildPlatform.canExecute stdenv.hostPlatform) ''
+    installShellCompletion --cmd ruff \
+      --bash <($out/bin/ruff generate-shell-completion bash) \
+      --fish <($out/bin/ruff generate-shell-completion fish) \
+      --zsh <($out/bin/ruff generate-shell-completion zsh)
+  '';
 
   passthru = {
     tests = {
@@ -82,11 +61,8 @@ python3Packages.buildPythonPackage rec {
     updateScript = nix-update-script { };
   };
 
-  # Run cargo tests
-  cargoCheckType = "debug";
-  postInstallCheck = ''
-    cargoCheckHook
-  '';
+  # # Run cargo tests
+  checkType = "debug";
 
   # Failing on darwin for an unclear reason.
   # According to the maintainers, those tests are from an experimental crate that isn't actually
@@ -121,8 +97,6 @@ python3Packages.buildPythonPackage rec {
   ];
   versionCheckProgramArg = [ "--version" ];
 
-  pythonImportsCheck = [ "ruff" ];
-
   meta = {
     description = "Extremely fast Python linter";
     homepage = "https://github.com/astral-sh/ruff";

pkgs/development/python-modules/ruff/default.nix

@@ -0,0 +1,27 @@
+{
+  buildPythonPackage,
+  pkgs,
+  rustPlatform,
+  installShellFiles,
+}:
+
+buildPythonPackage {
+  inherit (pkgs.ruff)
+    pname
+    version
+    src
+    postPatch
+    cargoDeps
+    postInstall
+    ;
+
+  pyproject = true;
+
+  nativeBuildInputs = [
+    installShellFiles
+    rustPlatform.cargoSetupHook
+    rustPlatform.maturinBuildHook
+  ];
+
+  pythonImportsCheck = [ "ruff" ];
+}

pkgs/top-level/python-packages.nix

@@ -14115,9 +14115,7 @@ self: super: with self; {
 
   rubymarshal = callPackage ../development/python-modules/rubymarshal { };
 
-  ruff = toPythonModule (pkgs.ruff.override {
-    python3Packages = self;
-  });
+  ruff = callPackage ../development/python-modules/ruff { };
 
   ruff-api = callPackage ../development/python-modules/ruff-api { };