BUG: DataFrame(EA2D) construction (#44593)

Author: jbrockmendel

pandas/core/internals/construction.py

@@ -294,10 +294,15 @@ def ndarray_to_mgr(
     if is_1d_only_ea_dtype(vdtype) or isinstance(dtype, ExtensionDtype):
         # GH#19157
 
-        if isinstance(values, np.ndarray) and values.ndim > 1:
+        if isinstance(values, (np.ndarray, ExtensionArray)) and values.ndim > 1:
             # GH#12513 a EA dtype passed with a 2D array, split into
             #  multiple EAs that view the values
-            values = [values[:, n] for n in range(values.shape[1])]
+            # error: No overload variant of "__getitem__" of "ExtensionArray"
+            # matches argument type "Tuple[slice, int]"
+            values = [
+                values[:, n]  # type: ignore[call-overload]
+                for n in range(values.shape[1])
+            ]
         else:
             values = [values]
 

pandas/tests/extension/base/dim2.py

@@ -14,6 +14,13 @@
 
 
 class Dim2CompatTests(BaseExtensionTests):
+    def test_frame_from_2d_array(self, data):
+        arr2d = data.repeat(2).reshape(-1, 2)
+
+        df = pd.DataFrame(arr2d)
+        expected = pd.DataFrame({0: arr2d[:, 0], 1: arr2d[:, 1]})
+        self.assert_frame_equal(df, expected)
+
     def test_swapaxes(self, data):
         arr2d = data.repeat(2).reshape(-1, 2)
 

pandas/tests/frame/test_constructors.py

@@ -70,6 +70,14 @@
 
 
 class TestDataFrameConstructors:
+    def test_constructor_from_2d_datetimearray(self):
+        dti = date_range("2016-01-01", periods=6, tz="US/Pacific")
+        dta = dti._data.reshape(3, 2)
+
+        df = DataFrame(dta)
+        expected = DataFrame({0: dta[:, 0], 1: dta[:, 1]})
+        tm.assert_frame_equal(df, expected)
+
     def test_constructor_dict_with_tzaware_scalar(self):
         # GH#42505
         dt = Timestamp("2019-11-03 01:00:00-0700").tz_convert("America/Los_Angeles")