python3Packages.MDP: reenable tests

Tests were disabled years ago by 140136ad95 (mdp: disable tests,
2017-09-14) because of missing dependencies that are not in nixpkgs, but
current version 3.6 prints a warning and run the tests just fine.

    ============================= test session starts ==============================
    platform darwin -- Python 3.9.6, pytest-6.2.5, py-1.10.0, pluggy-1.0.0
              python: 3.9.6.final.0
                 mdp: 3.6
     parallel python: NOT AVAILABLE: No module named 'pp'
              shogun: NOT AVAILABLE: No module named 'shogun'
              libsvm: NOT AVAILABLE: No module named 'libsvm'
              joblib: NOT AVAILABLE: No module named 'joblib'
             sklearn: NOT AVAILABLE: No module named 'scikits'
                numx: numpy 1.21.2
              symeig: symeig_fake
    Random Seed: 7710873

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

@@ -1,4 +1,10 @@
-{ lib, buildPythonPackage, fetchPypi, pytest, future, numpy }:
+{ lib
+, buildPythonPackage
+, fetchPypi
+, future
+, numpy
+, pytest
+}:
 
 buildPythonPackage rec {
   pname = "MDP";
@@ -9,11 +15,27 @@ buildPythonPackage rec {
     sha256 = "ac52a652ccbaed1857ff1209862f03bf9b06d093b12606fb410787da3aa65a0e";
   };
 
-  checkInputs = [ pytest ];
   propagatedBuildInputs = [ future numpy ];
 
-  # Tests disabled because of missing dependencies not in nix
-  doCheck = false;
+  checkInputs = [ pytest ];
+
+  doCheck = true;
+
+  pythonImportsCheck = [ "mdp" "bimdp" ];
+
+  postPatch = ''
+    # https://github.com/mdp-toolkit/mdp-toolkit/issues/92
+    substituteInPlace mdp/utils/routines.py --replace numx.typeDict numx.sctypeDict
+  '';
+
+  checkPhase = ''
+    runHook preCheck
+
+    pytest --seed 7710873 mdp
+    pytest --seed 7710873 bimdp
+
+    runHook postCheck
+  '';
 
   meta = with lib; {
     description = "Library for building complex data processing software by combining widely used machine learning algorithms";