Feature: adding detectin of MPI support via libmesh-config

pygriffin/config.py

 import os
 from pathlib import Path
+import subprocess
 
 try:
     from ConfigParser import ConfigParser
@@ -45,6 +46,18 @@ class PyGriffinConfig():
             'of the Griffin executable have failed.')
             raise RuntimeError(msg)
 
+        # check libMesh configuration for MPI
+        libmesh_config = self.griffin_dir / 'moose/libmesh/installed/bin/libmesh-config'
+
+        out = subprocess.Popen([libmesh_config, '--cxx'], stdout=subprocess.PIPE)
+
+        libmesh_config_out = out.stdout.read()
+
+        if 'mpi' in libmesh_config_out.decode():
+            self.mpi_enabled = True
+        else:
+            self.mpi_enabled = False
+
     def get(self, *args, **kwargs):
         """
         Attempts to get a configuration option from the .rc file.
@@ -75,6 +88,15 @@ class PyGriffinConfig():
     def griffin_exec(self):
         return self._griffin_exec
 
+    @property
+    def mpi_enabled(self):
+        return self._mpi_enabled
+
+    @mpi_enabled.setter
+    def mpi_enabled(self, val):
+        cv.check_type('MPI Enabled', val, bool)
+        self._mpi_enabled = val
+
     @griffin_exec.setter
     def griffin_exec(self, exec):
         cv.check_type('Griffin executable path', exec, (Path, str))

pygriffin/pygriffin.py

@@ -2,6 +2,7 @@ from numbers import Integral
 from pathlib import Path
 import subprocess
 from typing import Iterable
+import warnings
 
 import pygriffin.checkvalue as cv
 from pygriffin.config import PyGriffinConfig
@@ -41,7 +42,12 @@ class PyGriffin:
         cmd = []
 
         if self.n_procs > 1:
-            cmd += ['mpirun', '-n', str(self.n_procs)]
+            if self.config.mpi_enabled:
+                cmd += ['mpirun', '-n', str(self.n_procs)]
+            else:
+                msg = ("MPI is not enabled for this Griffin executable. "
+                       "The n_procs argument will be ignored.")
+                warnings.warn(msg)
 
         # add griffin executable to command line
         cmd.append(str(self.config.griffin_exec))