BUG: Bug in Panel indexing with an object-like (GH9140)

doc/source/whatsnew/v0.16.0.txt

@@ -56,7 +56,7 @@ Bug Fixes
 .. _whatsnew_0160.bug_fixes:
 
 - Fixed compatibility issue in ``DatetimeIndex`` affecting architectures where ``numpy.int_`` defaults to ``numpy.int32`` (:issue:`8943`)
-
+- Bug in Panel indexing with an object-like (:issue:`9140`)
 
 
 

pandas/core/panel.py

@@ -253,7 +253,7 @@ def from_dict(cls, data, intersect=False, orient='items', dtype=None):
     def __getitem__(self, key):
         if isinstance(self._info_axis, MultiIndex):
             return self._getitem_multilevel(key)
-        if lib.isscalar(key):
+        if not (_is_list_like(key) or isinstance(key, slice)):
             return super(Panel, self).__getitem__(key)
         return self.ix[key]
 

pandas/tests/test_indexing.py

@@ -2448,6 +2448,22 @@ def test_panel_getitem(self):
         result = panel.ix[['ItemA','ItemB']]
         tm.assert_panel_equal(result,expected)
 
+        # with an object-like
+        # GH 9140
+        class TestObject:
+            def __str__(self):
+                return "TestObject"
+
+        obj = TestObject()
+
+        p = Panel(np.random.randn(1,5,4), items=[obj],
+                  major_axis = date_range('1/1/2000', periods=5),
+                  minor_axis=['A', 'B', 'C', 'D'])
+
+        expected = p.iloc[0]
+        result = p[obj]
+        tm.assert_frame_equal(result, expected)
+
     def test_panel_setitem(self):
 
         # GH 7763