Minor QOL changes to translate test infrastructure

docs/porting/translate/index.md

@@ -27,6 +27,12 @@ You can create an overwrite file to manually set the threshold in you data direc
 
 ![image1.png](../../images/translate/image1.png)
 
+### Testing with Custom Data
+
+The default netcdf names can be overwritten by setting `self.override_input_netcdf_name` and/or `self.override_output_netcdf_name`
+for the input and output netcdf, respectively. These new names should be the entire file name (including, but not requiring,
+-In or -Out suffixes), excluding the `.nc` file tag. These files **must** be located in the same folder as the default files.
+
 ### Overwriting Arguments to your compute function
 
 The compute_func will be called automatically in the test. If your names in the netcdf are matching the `kwargs` of your function directly, no further action required:

ndsl/stencils/testing/test_translate.py

@@ -177,7 +177,28 @@ def test_sequential_savepoint(
         return
     if not case.exists:
         pytest.skip(f"Data at rank {case.grid.rank} does not exist.")
-    input_data = dataset_to_dict(case.ds_in)
+
+    if hasattr(case.testobj, "override_input_netcdf_name"):
+        import xarray as xr
+
+        from ndsl.logging import ndsl_log
+
+        out_data = (
+            xr.open_dataset(
+                os.path.join(
+                    case.data_dir, f"{case.testobj.override_input_netcdf_name}.nc"
+                )
+            )
+            .isel(rank=case.grid.rank)
+            .isel(savepoint=case.i_call)
+        )
+        input_data = dataset_to_dict(out_data)
+        ndsl_log.warning(
+            f"You are loading {case.testobj.override_input_netcdf_name} as a custom input file! Here be dragons."
+        )
+    else:
+        input_data = dataset_to_dict(case.ds_in)
+
     input_names = (
         case.testobj.serialnames(case.testobj.in_vars["data_vars"])
         + case.testobj.in_vars["parameters"]
@@ -196,7 +217,28 @@ def test_sequential_savepoint(
     output = case.testobj.compute(input_data)
     failing_names: List[str] = []
     passing_names: List[str] = []
-    all_ref_data = dataset_to_dict(case.ds_out)
+    if hasattr(case.testobj, "override_output_netcdf_name"):
+        import xarray as xr
+
+        from ndsl.logging import ndsl_log
+
+        out_data = (
+            xr.open_dataset(
+                os.path.join(
+                    case.data_dir, f"{case.testobj.override_output_netcdf_name}.nc"
+                )
+            )
+            .isel(rank=case.grid.rank)
+            .isel(savepoint=case.i_call)
+        )
+
+        output_data = dataset_to_dict(out_data)
+        ndsl_log.warning(
+            f"You are loading {case.testobj.override_output_netcdf_name} as a custom output file! Here be dragons."
+        )
+    else:
+        output_data = dataset_to_dict(case.ds_out)
+    all_ref_data = output_data
     ref_data_out = {}
     results = {}
 
@@ -460,6 +502,11 @@ def _save_datatree(
         varname = names[index]
         # Read in dimensions and attributes
         if hasattr(testobj, "outputs") and testobj.outputs != {}:
+            if not isinstance(testobj.outputs, dict):
+                raise ValueError(
+                    f"Expecting `outputs` on translate test to be a dict, got {type(testobj.outputs)}."
+                    " Are you overriding `self.outputs`?"
+                )
             dims = [
                 dim_name + f"_{index}" for dim_name in testobj.outputs[varname]["dims"]
             ]