From 561444c6a5e5c8b6773de9918587aea10ef66808 Mon Sep 17 00:00:00 2001
From: patrick <61934744+phofl@users.noreply.github.com>
Date: Thu, 28 Jan 2021 21:11:55 +0100
Subject: [PATCH 1/2] BUG: DataFrame constructor reordering elements with
 ndarray from datetime dtype not datetime64[ns] (#39442)

(cherry picked from commit 624621b266263b7faccad725c900abcecf4c068e)
---
 doc/source/whatsnew/v1.3.0.rst          |  0
 pandas/_libs/tslibs/conversion.pyx      |  2 +-
 pandas/tests/frame/test_constructors.py | 64 +++++++++++++++++++++++++
 3 files changed, 65 insertions(+), 1 deletion(-)
 create mode 100644 doc/source/whatsnew/v1.3.0.rst

diff --git a/doc/source/whatsnew/v1.3.0.rst b/doc/source/whatsnew/v1.3.0.rst
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/pandas/_libs/tslibs/conversion.pyx b/pandas/_libs/tslibs/conversion.pyx
index 3b52b4d499694..07507d5f5d2d4 100644
--- a/pandas/_libs/tslibs/conversion.pyx
+++ b/pandas/_libs/tslibs/conversion.pyx
@@ -224,7 +224,7 @@ def ensure_datetime64ns(arr: ndarray, copy: bool=True):
 
     ivalues = arr.view(np.int64).ravel("K")
 
-    result = np.empty(shape, dtype=DT64NS_DTYPE)
+    result = np.empty_like(arr, dtype=DT64NS_DTYPE)
     iresult = result.ravel("K").view(np.int64)
 
     if len(iresult) == 0:
diff --git a/pandas/tests/frame/test_constructors.py b/pandas/tests/frame/test_constructors.py
index 2300a8937991e..77287b6f1eab5 100644
--- a/pandas/tests/frame/test_constructors.py
+++ b/pandas/tests/frame/test_constructors.py
@@ -1936,6 +1936,70 @@ def test_constructor_datetimes_with_nulls(self, arr):
         expected = Series([np.dtype("datetime64[ns]")])
         tm.assert_series_equal(result, expected)
 
+    @pytest.mark.parametrize("order", ["K", "A", "C", "F"])
+    @pytest.mark.parametrize(
+        "dtype",
+        [
+            "datetime64[M]",
+            "datetime64[D]",
+            "datetime64[h]",
+            "datetime64[m]",
+            "datetime64[s]",
+            "datetime64[ms]",
+            "datetime64[us]",
+            "datetime64[ns]",
+        ],
+    )
+    def test_constructor_datetimes_non_ns(self, order, dtype):
+        na = np.array(
+            [
+                ["2015-01-01", "2015-01-02", "2015-01-03"],
+                ["2017-01-01", "2017-01-02", "2017-02-03"],
+            ],
+            dtype=dtype,
+            order=order,
+        )
+        df = DataFrame(na)
+        expected = DataFrame(
+            [
+                ["2015-01-01", "2015-01-02", "2015-01-03"],
+                ["2017-01-01", "2017-01-02", "2017-02-03"],
+            ]
+        )
+        expected = expected.astype(dtype=dtype)
+        tm.assert_frame_equal(df, expected)
+
+    @pytest.mark.parametrize("order", ["K", "A", "C", "F"])
+    @pytest.mark.parametrize(
+        "dtype",
+        [
+            "timedelta64[D]",
+            "timedelta64[h]",
+            "timedelta64[m]",
+            "timedelta64[s]",
+            "timedelta64[ms]",
+            "timedelta64[us]",
+            "timedelta64[ns]",
+        ],
+    )
+    def test_constructor_timedelta_non_ns(self, order, dtype):
+        na = np.array(
+            [
+                [np.timedelta64(1, "D"), np.timedelta64(2, "D")],
+                [np.timedelta64(4, "D"), np.timedelta64(5, "D")],
+            ],
+            dtype=dtype,
+            order=order,
+        )
+        df = DataFrame(na).astype("timedelta64[ns]")
+        expected = DataFrame(
+            [
+                [Timedelta(1, "D"), Timedelta(2, "D")],
+                [Timedelta(4, "D"), Timedelta(5, "D")],
+            ],
+        )
+        tm.assert_frame_equal(df, expected)
+
     def test_constructor_for_list_with_dtypes(self):
         # test list of lists/ndarrays
         df = DataFrame([np.arange(5) for x in range(5)])

From f8dbaf86f3db430f9c174fa28990232523cf4beb Mon Sep 17 00:00:00 2001
From: phofl <patrick_hoefler@gmx.net>
Date: Sat, 30 Jan 2021 02:42:31 +0100
Subject: [PATCH 2/2] Move whatsnew

---
 doc/source/whatsnew/v1.2.2.rst | 1 +
 doc/source/whatsnew/v1.3.0.rst | 0
 2 files changed, 1 insertion(+)
 delete mode 100644 doc/source/whatsnew/v1.3.0.rst

diff --git a/doc/source/whatsnew/v1.2.2.rst b/doc/source/whatsnew/v1.2.2.rst
index 95fbbaf5d566e..5523eaaa5781a 100644
--- a/doc/source/whatsnew/v1.2.2.rst
+++ b/doc/source/whatsnew/v1.2.2.rst
@@ -14,6 +14,7 @@ including other versions of pandas.
 
 Fixed regressions
 ~~~~~~~~~~~~~~~~~
+- Fixed regression in :class:`DataFrame` constructor reordering element when construction from datetime ndarray with dtype not ``"datetime64[ns]"`` (:issue:`39422`)
 - Fixed regression in :meth:`~DataFrame.to_pickle` failing to create bz2/xz compressed pickle files with ``protocol=5`` (:issue:`39002`)
 -
 
diff --git a/doc/source/whatsnew/v1.3.0.rst b/doc/source/whatsnew/v1.3.0.rst
deleted file mode 100644
index e69de29bb2d1d..0000000000000