python3.pkgs.pypaBuildHook: fix conflicts via propagated inputs 2

A follow up on #254547

As of now the hook still propagated `wheel` into the build environment which lead to a collision error as soon as any other version of wheel gets introduced as a dependency.

This makes the nixpkgs python infra more suitable for use with dynamic dependency versions like generated by 2nix tools.

pkgs/development/interpreters/python/hooks/default.nix

@@ -2,7 +2,6 @@ self: dontUse: with self;
 
 let
   inherit (python) pythonOnBuildForHost;
-  inherit (pkgs) runCommand;
   pythonInterpreter = pythonOnBuildForHost.interpreter;
   pythonSitePackages = python.sitePackages;
   pythonCheckInterpreter = python.interpreter;
@@ -58,7 +57,6 @@ in {
   pypaBuildHook = callPackage ({ makePythonHook, build, wheel }:
     makePythonHook {
       name = "pypa-build-hook.sh";
-      propagatedBuildInputs = [ wheel ];
       substitutions = {
         inherit build;
       };
@@ -68,8 +66,8 @@ in {
       # Such conflicts don't happen within the standard nixpkgs python package
       #   set, but in downstream projects that build packages depending on other
       #   versions of this hook's dependencies.
-      passthru.tests = import ./pypa-build-hook-test.nix {
-        inherit pythonOnBuildForHost runCommand;
+      passthru.tests = callPackage ./pypa-build-hook-tests.nix {
+        inherit pythonOnBuildForHost;
       };
     } ./pypa-build-hook.sh) {
       inherit (pythonOnBuildForHost.pkgs) build;

pkgs/development/interpreters/python/hooks/pypa-build-hook-test.nix → pkgs/development/interpreters/python/hooks/pypa-build-hook-tests.nix

@@ -25,6 +25,7 @@
         # At least one dependency of `build` should be included here to
         # keep the test meaningful
         (mkConflict pythonOnBuildForHost.pkgs.tomli)
+        (mkConflict pythonOnBuildForHost.pkgs.wheel)
         # setuptools is also needed to build the example project
         pythonOnBuildForHost.pkgs.setuptools
       ];

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

@@ -11,6 +11,7 @@
 , pytest-rerunfailures
 , pytest-xdist
 , pytestCheckHook
+, python3
 , pythonOlder
 , setuptools
 , tomli
@@ -93,6 +94,12 @@ buildPythonPackage rec {
     "build"
   ];
 
+  # Add the wheel dependency via a wrapper.
+  # DO NOT use propagatedBuildInputs to prevent leakage into the build env.
+  makeWrapperArgs = [
+    ''--suffix PYTHONPATH : "${wheel}/${python3.sitePackages}"''
+  ];
+
   meta = with lib; {
     mainProgram = "pyproject-build";
     description = "Simple, correct PEP517 package builder";