Update test to use fesom download

Also move the data to a pytest fixture :)

Author: VeckoTheGecko

parcels/field.py

@@ -143,7 +143,7 @@ def __init__(
         self,
         name: str,
         data: xr.DataArray | ux.UxDataArray,
-        grid: ux.UxGrid | None = None,  # To do : Once parcels.Grid class is added, allow for it to be passed here
+        grid: ux.Grid | None = None,  # To do : Once parcels.Grid class is added, allow for it to be passed here
         mesh_type: Mesh = "flat",
         interp_method: Callable | None = None,
         allow_time_extrapolation: bool | None = None,

tests/v4/test_uxarray_fieldset.py

@@ -1,6 +1,6 @@
-import os
 from datetime import timedelta
 
+import pytest
 import uxarray as ux
 
 from parcels import (
@@ -9,70 +9,48 @@
     ParticleSet,
     UXPiecewiseConstantFace,
     UXPiecewiseLinearNode,
+    download_example_dataset,
 )
 
-# Get path of this script
-V4_TEST_DATA = f"{os.path.dirname(__file__)}/test_data"
 
-
-def test_fesom_fieldset():
-    # Load a FESOM dataset
-    grid_path = f"{V4_TEST_DATA}/fesom_channel.nc"
+@pytest.fixture
+def ds_fesom_channel() -> ux.UxDataset:
+    fesom_path = download_example_dataset("FESOM_periodic_channel")
+    grid_path = f"{fesom_path}/fesom_channel.nc"
     data_path = [
-        f"{V4_TEST_DATA}/u.fesom_channel.nc",
-        f"{V4_TEST_DATA}/v.fesom_channel.nc",
-        f"{V4_TEST_DATA}/w.fesom_channel.nc",
+        f"{fesom_path}/u.fesom_channel.nc",
+        f"{fesom_path}/v.fesom_channel.nc",
+        f"{fesom_path}/w.fesom_channel.nc",
     ]
-    ds = ux.open_mfdataset(grid_path, data_path)
-    ds = ds.rename_vars({"u": "U", "v": "V", "w": "W"})
-    fieldset = FieldSet([ds])
+    ds = ux.open_mfdataset(grid_path, data_path).rename_vars({"u": "U", "v": "V", "w": "W"})
+    return ds.copy(deep=True)
+
+
+def test_fesom_fieldset(ds_fesom_channel):
+    fieldset = FieldSet([ds_fesom_channel])
     fieldset._check_complete()
     # Check that the fieldset has the expected properties
-    assert fieldset.datasets[0] == ds
+    assert fieldset.datasets[0] == ds_fesom_channel
 
 
-def test_fesom_in_particleset():
-    grid_path = f"{V4_TEST_DATA}/fesom_channel.nc"
-    data_path = [
-        f"{V4_TEST_DATA}/u.fesom_channel.nc",
-        f"{V4_TEST_DATA}/v.fesom_channel.nc",
-        f"{V4_TEST_DATA}/w.fesom_channel.nc",
-    ]
-    ds = ux.open_mfdataset(grid_path, data_path)
-    ds = ds.rename_vars({"u": "U", "v": "V", "w": "W"})
-    fieldset = FieldSet([ds])
+def test_fesom_in_particleset(ds_fesom_channel):
+    fieldset = FieldSet([ds_fesom_channel])
     # Check that the fieldset has the expected properties
-    assert fieldset.datasets[0] == ds
+    assert fieldset.datasets[0] == ds_fesom_channel
     pset = ParticleSet(fieldset, pclass=Particle)
     assert pset.fieldset == fieldset
 
 
-def test_set_interp_methods():
-    grid_path = f"{V4_TEST_DATA}/fesom_channel.nc"
-    data_path = [
-        f"{V4_TEST_DATA}/u.fesom_channel.nc",
-        f"{V4_TEST_DATA}/v.fesom_channel.nc",
-        f"{V4_TEST_DATA}/w.fesom_channel.nc",
-    ]
-    ds = ux.open_mfdataset(grid_path, data_path)
-    ds = ds.rename_vars({"u": "U", "v": "V", "w": "W"})
-    fieldset = FieldSet([ds])
+def test_set_interp_methods(ds_fesom_channel):
+    fieldset = FieldSet([ds_fesom_channel])
     # Set the interpolation method for each field
     fieldset.U.interp_method = UXPiecewiseConstantFace
     fieldset.V.interp_method = UXPiecewiseConstantFace
     fieldset.W.interp_method = UXPiecewiseLinearNode
 
 
-def test_fesom_channel():
-    grid_path = f"{V4_TEST_DATA}/fesom_channel.nc"
-    data_path = [
-        f"{V4_TEST_DATA}/u.fesom_channel.nc",
-        f"{V4_TEST_DATA}/v.fesom_channel.nc",
-        f"{V4_TEST_DATA}/w.fesom_channel.nc",
-    ]
-    ds = ux.open_mfdataset(grid_path, data_path)
-    ds = ds.rename_vars({"u": "U", "v": "V", "w": "W"})
-    fieldset = FieldSet([ds])
+def test_fesom_channel(ds_fesom_channel):
+    fieldset = FieldSet([ds_fesom_channel])
     # Set the interpolation method for each field
     fieldset.U.interp_method = UXPiecewiseConstantFace
     fieldset.V.interp_method = UXPiecewiseConstantFace