raise if netcdf-c is parallel OK but we don't have mpi4py

Author: ocefpaf

setup.py

@@ -9,13 +9,6 @@
 
 
 
-has_mpi4py = False
-try:
-    import mpi4py
-    has_mpi4py = True
-except ImportError:
-    print(f"mpi4py is not installed. Parallel support will be off even if netcdf-c supports it.")
-
 open_kwargs = {'encoding': 'utf-8'}
 
 
@@ -56,8 +49,6 @@ def check_ifnetcdf4(netcdf4_includedir):
 
 def check_has_parallel_support(inc_dirs: list) -> bool:
     has_parallel_support = False
-    if not has_mpi4py:
-        return has_parallel_support
 
     for d in inc_dirs:
         ncmetapath = os.path.join(d,'netcdf_meta.h')
@@ -408,6 +399,12 @@ def _populate_hdf5_info(dirstosearch, inc_dirs, libs, lib_dirs):
     print(f"netcdf lib {has_has_not} parallel functions")
 
     if has_parallel_support:
+        try:
+            import mpi4py
+        except ImportError:
+            msg = "Parallel support requires mpi4py but it is not installed."
+            raise ImportError(msg)
+
         inc_dirs.append(mpi4py.get_include())
         # mpi_incdir should not be needed if using nc-config
         # (should be included in nc-config --cflags)