make compatible with non-coupling-enabled versions of grudge

examples/thermally-coupled-mpi.py

@@ -97,6 +97,13 @@ def main(ctx_factory=cl.create_some_context, use_logmgr=True,
     if casename is None:
         casename = "mirgecom"
 
+    try:
+        from grudge.discretization import PartID  # noqa: F401
+    except ImportError:
+        from warnings import warn
+        warn("This example requires a coupling-enabled branch of grudge; exiting.")
+        return
+
     from mpi4py import MPI
     comm = MPI.COMM_WORLD
     rank = comm.Get_rank()

mirgecom/multiphysics/thermally_coupled_fluid_wall.py

@@ -53,7 +53,6 @@
 
 from grudge.trace_pair import (
     TracePair,
-    inter_volume_trace_pairs
 )
 from grudge.dof_desc import (
     DISCR_TAG_BASE,
@@ -661,6 +660,8 @@ def _kappa_inter_volume_trace_pairs(
 
     pairwise_kappa = {
         (fluid_dd, wall_dd): (fluid_kappa, wall_kappa)}
+    from grudge.trace_pair import \
+        inter_volume_trace_pairs  # pylint: disable=no-name-in-module
     return inter_volume_trace_pairs(
         dcoll, pairwise_kappa, comm_tag=_KappaInterVolTag)
 
@@ -674,6 +675,8 @@ def _temperature_inter_volume_trace_pairs(
     pairwise_temperature = {
         (fluid_dd, wall_dd):
             (fluid_state.temperature, wall_temperature)}
+    from grudge.trace_pair import \
+        inter_volume_trace_pairs  # pylint: disable=no-name-in-module
     return inter_volume_trace_pairs(
         dcoll, pairwise_temperature, comm_tag=_TemperatureInterVolTag)
 
@@ -687,6 +690,8 @@ def _grad_temperature_inter_volume_trace_pairs(
     pairwise_grad_temperature = {
         (fluid_dd, wall_dd):
             (fluid_grad_temperature, wall_grad_temperature)}
+    from grudge.trace_pair import \
+        inter_volume_trace_pairs  # pylint: disable=no-name-in-module
     return inter_volume_trace_pairs(
         dcoll, pairwise_grad_temperature, comm_tag=_GradTemperatureInterVolTag)
 

mirgecom/simutil.py

@@ -78,7 +78,7 @@
 from mirgecom.viscous import get_viscous_timestep
 
 from typing import List, Dict, Optional
-from grudge.discretization import DiscretizationCollection, PartID
+from grudge.discretization import DiscretizationCollection
 from grudge.dof_desc import DD_VOLUME_ALL
 from mirgecom.utils import normalize_boundaries
 import pyopencl as cl
@@ -892,6 +892,9 @@ def partition_generator_func(mesh, tag_to_elements, num_ranks):
             if np.any(volume_index_per_element < 0):
                 raise ValueError("Missing volume specification for some elements.")
 
+            from grudge.discretization import \
+                PartID  # pylint: disable=no-name-in-module
+
             part_id_to_elements = {
                 PartID(volumes[vol_idx], rank):
                     np.where(

test/test_multiphysics.py

@@ -165,6 +165,11 @@ def get_rhs(t, u):
 def test_thermally_coupled_fluid_wall(
         actx_factory, order, use_overintegration, visualize=False):
     """Check the thermally-coupled fluid/wall interface."""
+    try:
+        from grudge.discretization import PartID  # noqa: F401
+    except ImportError:
+        pytest.skip("Test requires a coupling-enabled branch of grudge.")
+
     actx = actx_factory()
 
     from pytools.convergence import EOCRecorder