Added test for issue #6002 (currently fails)

xarray/tests/test_transpose.py

@@ -0,0 +1,43 @@
+from collections import OrderedDict
+
+import numpy as np
+import pytest
+from numpy.testing import assert_allclose
+
+import xarray as xr
+
+
+def test_issue_6002():
+    """Ref: https://github.com/pydata/xarray/issues/6002"""
+
+    n_time = 1  # 1 : Fails, 2 : everything is fine
+
+    from xarray.core.options import OPTIONS
+
+    OPTIONS["use_bottleneck"] = True  # Set to False for work-around
+
+    # Build some dataset
+    dirs = np.linspace(0, 360, num=121)
+    freqs = np.linspace(0, 4, num=192)
+    spec_data = np.random.random(size=(n_time, 192, 121))
+
+    dims = ("time", "freq", "dir")
+    coords = OrderedDict()
+    coords["time"] = range(n_time)
+    coords["freq"] = freqs
+    coords["dir"] = dirs
+
+    xdata = xr.DataArray(
+        data=spec_data,
+        coords=coords,
+        dims=dims,
+        name="Spec name",
+    ).to_dataset()
+
+    expected = np.max(spec_data)
+
+    xdata = xdata.transpose(..., "freq")  # remove this line and the script will run
+
+    tm = xdata.max()
+
+    assert_allclose(tm, expected)