Merge branch 'main' into Series-dt-isocalendar-docs

Author: tswast

ci/deps/actions-38-downstream_compat.yaml

@@ -60,7 +60,7 @@ dependencies:
   - cftime
   - dask
   - ipython
-  - geopandas
+  - geopandas-base
   - seaborn
   - scikit-learn
   - statsmodels

doc/source/whatsnew/v1.5.0.rst

@@ -92,6 +92,9 @@ Other enhancements
 - :class:`Series` and :class:`DataFrame` with ``IntegerDtype`` now supports bitwise operations (:issue:`34463`)
 - Add ``milliseconds`` field support for :class:`~pandas.DateOffset` (:issue:`43371`)
 - :meth:`DataFrame.reset_index` now accepts a ``names`` argument which renames the index names (:issue:`6878`)
+- :meth:`pd.concat` now raises when ``levels`` is given but ``keys`` is None (:issue:`46653`)
+- :meth:`pd.concat` now raises when ``levels`` contains duplicate values (:issue:`46653`)
+-
 
 .. ---------------------------------------------------------------------------
 .. _whatsnew_150.notable_bug_fixes:

pandas/core/reshape/concat.py

@@ -668,6 +668,8 @@ def _get_concat_axis(self) -> Index:
             return idx
 
         if self.keys is None:
+            if self.levels is not None:
+                raise ValueError("levels supported only when keys is not None")
             concat_axis = _concat_indexes(indexes)
         else:
             concat_axis = _make_concat_multiindex(
@@ -712,6 +714,10 @@ def _make_concat_multiindex(indexes, keys, levels=None, names=None) -> MultiInde
         else:
             levels = [ensure_index(x) for x in levels]
 
+    for level in levels:
+        if not level.is_unique:
+            raise ValueError(f"Level values not unique: {level.tolist()}")
+
     if not all_indexes_same(indexes) or not all(level.is_unique for level in levels):
         codes_list = []
 

pandas/tests/reshape/concat/test_index.py

@@ -371,3 +371,19 @@ def test_concat_with_key_not_unique(self):
             out_b = df_b.loc[("x", 0), :]
 
         tm.assert_frame_equal(out_a, out_b)
+
+    def test_concat_with_duplicated_levels(self):
+        # keyword levels should be unique
+        df1 = DataFrame({"A": [1]}, index=["x"])
+        df2 = DataFrame({"A": [1]}, index=["y"])
+        msg = r"Level values not unique: \['x', 'y', 'y'\]"
+        with pytest.raises(ValueError, match=msg):
+            concat([df1, df2], keys=["x", "y"], levels=[["x", "y", "y"]])
+
+    @pytest.mark.parametrize("levels", [[["x", "y"]], [["x", "y", "y"]]])
+    def test_concat_with_levels_with_none_keys(self, levels):
+        df1 = DataFrame({"A": [1]}, index=["x"])
+        df2 = DataFrame({"A": [1]}, index=["y"])
+        msg = "levels supported only when keys is not None"
+        with pytest.raises(ValueError, match=msg):
+            concat([df1, df2], levels=levels)

pandas/tests/test_downstream.py

@@ -8,7 +8,6 @@
 import numpy as np
 import pytest
 
-from pandas.compat import is_platform_windows
 import pandas.util._test_decorators as td
 
 import pandas as pd
@@ -224,20 +223,13 @@ def test_pandas_datareader():
     pandas_datareader.DataReader("F", "quandl", "2017-01-01", "2017-02-01")
 
 
-# importing from pandas, Cython import warning
-@pytest.mark.filterwarnings("ignore:can't resolve:ImportWarning")
-@pytest.mark.xfail(
-    is_platform_windows(),
-    raises=ImportError,
-    reason="ImportError: the 'read_file' function requires the 'fiona' package, "
-    "but it is not installed or does not import correctly",
-    strict=False,
-)
 def test_geopandas():
 
     geopandas = import_module("geopandas")
-    fp = geopandas.datasets.get_path("naturalearth_lowres")
-    assert geopandas.read_file(fp) is not None
+    gdf = geopandas.GeoDataFrame(
+        {"col": [1, 2, 3], "geometry": geopandas.points_from_xy([1, 2, 3], [1, 2, 3])}
+    )
+    assert gdf[["col", "geometry"]].geometry.x.equals(Series([1.0, 2.0, 3.0]))
 
 
 # Cython import warning