BUG: Fix Index.get_level_values() mishandling of boolean, pd.NA, np.nan, and pd.NaT levels

pandas/core/indexes/base.py

@@ -39,6 +39,7 @@
     is_datetime_array,
     no_default,
 )
+from pandas._libs.missing import is_matching_na
 from pandas._libs.tslibs import (
     OutOfBoundsDatetime,
     Timestamp,
@@ -2118,6 +2119,30 @@ def _sort_levels_monotonic(self) -> Self:
         """
         return self
 
+    @final
+    def _validate_positional_level(self, level: int) -> None:
+        """
+        Validate that level is 0 or -1 for single-level Index.
+
+        Parameters
+        ----------
+        level : int
+            The positional level to validate.
+
+        Raises
+        ------
+        IndexError
+            If level is not 0 or -1.
+        """
+        if level < 0 and level != -1:
+            raise IndexError(
+                f"Too many levels: Index has only 1 level, not {level + 1}"
+            )
+        elif level > 0:
+            raise IndexError(
+                f"Too many levels: Index has only 1 level, not {level + 1}"
+            )
+
     @final
     def _validate_index_level(self, level) -> None:
         """
@@ -2127,21 +2152,59 @@ def _validate_index_level(self, level) -> None:
         verification must be done like in MultiIndex.
 
         """
-        if isinstance(level, int):
-            if level < 0 and level != -1:
-                raise IndexError(
-                    "Too many levels: Index has only 1 level, "
-                    f"{level} is not a valid level number"
-                )
-            if level > 0:
-                raise IndexError(
-                    f"Too many levels: Index has only 1 level, not {level + 1}"
-                )
-        elif level != self.name:
+        level_is_na = isna(level)
+        name_is_na = isna(self.name)
+
+        if level_is_na and name_is_na:
+            if is_matching_na(level, self.name):
+                return
+            raise KeyError(
+                f"Requested level ({level}) does not match index name ({self.name})"
+            )
+
+        if level_is_na:
+            raise KeyError(
+                f"Requested level ({level}) does not match index name ({self.name})"
+            )
+
+        if name_is_na:
+            if lib.is_integer(level):
+                self._validate_positional_level(level)
+                return
+            raise KeyError(
+                f"Requested level ({level}) does not match index name ({self.name})"
+            )
+
+        if isinstance(level, bool) and isinstance(self.name, bool):
+            if level == self.name:
+                return
+            raise KeyError(
+                f"Requested level ({level}) does not match index name ({self.name})"
+            )
+
+        if lib.is_integer(level):
+            if (
+                isinstance(self.name, int)
+                and not isinstance(self.name, bool)
+                and level == self.name
+            ):
+                return
+
+            self._validate_positional_level(level)
+            return
+
+        if isinstance(self.name, bool):
             raise KeyError(
                 f"Requested level ({level}) does not match index name ({self.name})"
             )
 
+        if level == self.name:
+            return
+
+        raise KeyError(
+            f"Requested level ({level}) does not match index name ({self.name})"
+        )
+
     def _get_level_number(self, level) -> int:
         self._validate_index_level(level)
         return 0

pandas/tests/indexes/test_base.py

@@ -962,6 +962,118 @@ def test_get_level_values(self, index, name, level):
         result = expected.get_level_values(level)
         tm.assert_index_equal(result, expected)
 
+    def test_get_level_values_boolean_name(self):
+        # GH#62175
+        idx = Index([1, 2, 3], name=True)
+        result = idx.get_level_values(True)
+        tm.assert_index_equal(result, idx)
+
+        idx = Index([1, 2, 3], name=False)
+        result = idx.get_level_values(False)
+        tm.assert_index_equal(result, idx)
+
+        idx = Index([1, 2, 3], name=True)
+        msg = r"Requested level \(False\) does not match index name \(True\)"
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(False)
+
+        msg = r"Too many levels: Index has only 1 level"
+        with pytest.raises(IndexError, match=msg):
+            idx.get_level_values(1)
+
+    def test_get_level_values_na_types(self):
+        # GH#62175
+        idx = Index([1, 2, 3], name=pd.NA)
+        result = idx.get_level_values(pd.NA)
+        tm.assert_index_equal(result, idx)
+
+        msg = r"Requested level \(.+\) does not match index name \(.+\)"
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(np.nan)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(None)
+
+        idx = Index([1, 2, 3], name=np.nan)
+        result = idx.get_level_values(np.nan)
+        tm.assert_index_equal(result, idx)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(pd.NA)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(None)
+
+        idx = Index([1, 2, 3], name=None)
+        result = idx.get_level_values(0)
+        tm.assert_index_equal(result, idx)
+
+        result = idx.get_level_values(-1)
+        tm.assert_index_equal(result, idx)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(pd.NA)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(np.nan)
+
+        idx = Index([1, 2, 3], name=pd.NaT)
+        result = idx.get_level_values(pd.NaT)
+        tm.assert_index_equal(result, idx)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(np.nan)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(pd.NA)
+
+    def test_get_level_values_integer_name_vs_position(self):
+        # GH#62175
+        idx = Index([1, 2, 3], name=0)
+        result = idx.get_level_values(0)
+        tm.assert_index_equal(result, idx)
+
+        result = idx.get_level_values(-1)
+        tm.assert_index_equal(result, idx)
+
+        idx = Index([1, 2, 3], name=5)
+        result = idx.get_level_values(5)
+        tm.assert_index_equal(result, idx)
+
+        result = idx.get_level_values(0)
+        tm.assert_index_equal(result, idx)
+
+        msg = r"Too many levels: Index has only 1 level, not 2"
+        with pytest.raises(IndexError, match=msg):
+            idx.get_level_values(1)
+
+        msg = r"Too many levels: Index has only 1 level, not 1"
+        with pytest.raises(IndexError, match=msg):
+            idx.get_level_values(-2)
+
+    def test_get_level_values_error_messages(self):
+        # GH#62175
+        idx = Index([1, 2, 3], name="foo")
+
+        msg = r"Requested level \(bar\) does not match index name \(foo\)"
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values("bar")
+
+        msg = r"Too many levels: Index has only 1 level, not 2"
+        with pytest.raises(IndexError, match=msg):
+            idx.get_level_values(1)
+
+        msg = r"Too many levels: Index has only 1 level, not 1"
+        with pytest.raises(IndexError, match=msg):
+            idx.get_level_values(-2)
+
+        msg = r"Requested level \(.+\) does not match index name \(foo\)"
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(pd.NA)
+
+        with pytest.raises(KeyError, match=msg):
+            idx.get_level_values(np.nan)
+
     def test_slice_keep_name(self):
         index = Index(["a", "b"], name="asdf")
         assert index.name == index[1:].name