paraview: include numpy in python environment

The Python filter functionality in Paraview requires numpy, which is currently not included.
Changes are based on the discussion in issue #37118.

pkgs/applications/graphics/paraview/default.nix

@@ -1,5 +1,5 @@
 {
-stdenv, fetchFromGitHub, cmake
+stdenv, fetchFromGitHub, cmake, makeWrapper
 ,qtbase, qttools, python, libGLU_combined
 ,libXt, qtx11extras, qtxmlpatterns
 }:
@@ -35,10 +35,12 @@ stdenv.mkDerivation rec {
 
   nativeBuildInputs = [
     cmake
+    makeWrapper
   ];
 
   buildInputs = [
     python
+    python.pkgs.numpy
     libGLU_combined
     libXt
     qtbase
@@ -47,6 +49,16 @@ stdenv.mkDerivation rec {
     qtxmlpatterns
   ];
 
+  # Paraview links into the Python library, resolving symbolic links on the way,
+  # so we need to put the correct sitePackages (with numpy) back on the path
+  postInstall = ''
+    wrapProgram $out/bin/paraview \
+      --set PYTHONPATH "${python.pkgs.numpy}/${python.sitePackages}"
+    wrapProgram $out/bin/pvbatch \
+      --set PYTHONPATH "${python.pkgs.numpy}/${python.sitePackages}"
+    wrapProgram $out/bin/pvpython \
+      --set PYTHONPATH "${python.pkgs.numpy}/${python.sitePackages}"
+  '';
 
   meta = {
     homepage = http://www.paraview.org/;