Add tests

Author: dcherian

cf_xarray/tests/__init__.py

@@ -0,0 +1,41 @@
+import re
+from contextlib import contextmanager
+
+import dask
+import pytest
+
+
+@contextmanager
+def raises_regex(error, pattern):
+    __tracebackhide__ = True
+    with pytest.raises(error) as excinfo:
+        yield
+    message = str(excinfo.value)
+    if not re.search(pattern, message):
+        raise AssertionError(
+            f"exception {excinfo.value!r} did not match pattern {pattern!r}"
+        )
+
+
+class CountingScheduler:
+    """ Simple dask scheduler counting the number of computes.
+
+    Reference: https://stackoverflow.com/questions/53289286/ """
+
+    def __init__(self, max_computes=0):
+        self.total_computes = 0
+        self.max_computes = max_computes
+
+    def __call__(self, dsk, keys, **kwargs):
+        self.total_computes += 1
+        if self.total_computes > self.max_computes:
+            raise RuntimeError(
+                "Too many computes. Total: %d > max: %d."
+                % (self.total_computes, self.max_computes)
+            )
+        return dask.get(dsk, keys, **kwargs)
+
+
+def raise_if_dask_computes(max_computes=0):
+    scheduler = CountingScheduler(max_computes)
+    return dask.config.set(scheduler=scheduler)

cf_xarray/tests/test_accessor.py

@@ -0,0 +1,52 @@
+import pytest
+import xarray as xr
+from xarray.testing import assert_identical
+
+import cf_xarray  # noqa
+
+from . import raise_if_dask_computes
+
+ds = xr.tutorial.open_dataset("air_temperature").isel(time=slice(4))
+objects = [
+    pytest.param(ds, marks=pytest.mark.xfail),
+    ds.air,
+    pytest.param(ds.chunk({"lat": 5}), marks=pytest.mark.xfail),
+    ds.air.chunk({"lat": 5}),
+]
+
+
+@pytest.mark.parametrize("obj", objects)
+def test_wrapped_classes(obj):
+    with raise_if_dask_computes():
+        expected = obj.resample(time="M").mean("lat")
+        actual = obj.cf.resample(T="M").mean("Y")
+    assert_identical(expected, actual)
+
+    # groupby
+    # rolling
+    # coarsen
+    # weighted
+
+
+@pytest.mark.parametrize("obj", objects)
+def test_other_methods(obj):
+    with raise_if_dask_computes():
+        expected = obj.isel(time=slice(2))
+        actual = obj.cf.isel(T=slice(2))
+    assert_identical(expected, actual)
+
+    with raise_if_dask_computes():
+        expected = obj.sum("time")
+        actual = obj.cf.sum("T")
+    assert_identical(expected, actual)
+
+
+@pytest.mark.parametrize("obj", objects)
+def test_plot(obj):
+    obj.isel(time=1).cf.plot(x="X", y="Y")
+    obj.isel(time=1).cf.plot.contourf(x="X", y="Y")
+
+    obj.cf.plot(x="X", y="Y", col="T")
+    obj.cf.plot.contourf(x="X", y="Y", col="T")
+
+    obj.isel(lat=[0, 1], lon=1).cf.plot.line(x="T", hue="Y")

ci/environment.yaml

@@ -1,4 +1,4 @@
-name: xcoare-test
+name: cf_xarray_test
 channels:
   - conda-forge
 dependencies: