Add test with output; mark as xfail

This test is marked with xfail since the changes required to support
particlefile will require a significant overhaul of the particlefile
module which is out of scope for this PR

Author: fluidnumericsJoe

tests/v4/test_particleset.py

@@ -1,5 +1,7 @@
 from datetime import timedelta
 
+import pytest
+
 from parcels import (
     AdvectionEE,
     Field,
@@ -13,7 +15,48 @@
 from parcels.uxgrid import UxGrid
 
 
-def test_uxstommel_gyre():
+@pytest.mark.parametrize("verbose_progress", [True, False])
+def test_uxstommelgyre_pset_execute(verbose_progress):
+    ds = datasets_unstructured["stommel_gyre_delaunay"]
+    grid = UxGrid(grid=ds.uxgrid, z=ds.coords["nz"])
+    U = Field(
+        name="U",
+        data=ds.U,
+        grid=grid,
+        mesh_type="spherical",
+        interp_method=UXPiecewiseConstantFace,
+    )
+    V = Field(
+        name="V",
+        data=ds.V,
+        grid=grid,
+        mesh_type="spherical",
+        interp_method=UXPiecewiseConstantFace,
+    )
+    P = Field(
+        name="P",
+        data=ds.p,
+        grid=grid,
+        mesh_type="spherical",
+        interp_method=UXPiecewiseConstantFace,
+    )
+    UV = VectorField(name="UV", U=U, V=V)
+    fieldset = FieldSet([UV, UV.U, UV.V, P])
+    pset = ParticleSet(
+        fieldset,
+        lon=[30.0],
+        lat=[5.0],
+        depth=[50.0],
+        time=[0.0],
+        pclass=Particle,
+    )
+    pset.execute(
+        runtime=timedelta(minutes=10), dt=timedelta(seconds=60), pyfunc=AdvectionEE, verbose_progress=verbose_progress
+    )
+
+
+@pytest.mark.xfail(reason="Output file not implemented yet")
+def test_uxstommelgyre_pset_execute_output():
     ds = datasets_unstructured["stommel_gyre_delaunay"]
     grid = UxGrid(grid=ds.uxgrid, z=ds.coords["nz"])
     U = Field(
@@ -47,4 +90,8 @@ def test_uxstommel_gyre():
         time=[0.0],
         pclass=Particle,
     )
-    pset.execute(runtime=timedelta(minutes=10), dt=timedelta(seconds=60), pyfunc=AdvectionEE, verbose_progress=False)
+    output_file = pset.ParticleFile(
+        name="stommel_uxarray_particles.zarr",  # the file name
+        outputdt=timedelta(minutes=5),  # the time step of the outputs
+    )
+    pset.execute(runtime=timedelta(minutes=10), dt=timedelta(seconds=60), pyfunc=AdvectionEE, output_file=output_file)