BUG: Fix maximum/minimum for object arrays in Python 3.

Use PyObject_RichCompareBool instead of PyObject_Cmp.

3 files changed, 64 insertions, 26 deletions

diff --git a/numpy/core/src/umath/funcs.inc.src b/numpy/core/src/umath/funcs.inc.src
index a76adaa39..a8db99d5d 100644
--- a/numpy/core/src/umath/funcs.inc.src
+++ b/numpy/core/src/umath/funcs.inc.src
@@ -54,6 +54,34 @@ npy_ObjectPower(PyObject *x, PyObject *y)
     return PyNumber_Power(x, y, Py_None);
 }
 
+
+#if defined(NPY_PY3K)
+/**begin repeat
+ * #Kind = Max, Min#
+ * #OP = Py_GE, Py_LE#
+ */
+static PyObject *
+npy_Object@Kind@(PyObject *i1, PyObject *i2)
+{
+    PyObject *result;
+    int cmp;
+
+    cmp = PyObject_RichCompareBool(i1, i2, @OP@);
+    if (cmp < 0) {
+        return NULL;
+    }
+    if (cmp == 1) {
+        result = i1;
+    }
+    else {
+        result = i2;
+    }
+    Py_INCREF(result);
+    return result;
+}
+/**end repeat**/
+
+#else
 /**begin repeat
  * #Kind = Max, Min#
  * #OP = >=, <=#
@@ -77,6 +105,8 @@ npy_Object@Kind@(PyObject *i1, PyObject *i2)
     return result;
 }
 /**end repeat**/
+#endif
+
 
 /* Emulates Python's 'a or b' behavior */
 static PyObject *
diff --git a/numpy/core/tests/test_multiarray.py b/numpy/core/tests/test_multiarray.py
index 88d52568c..118e0b4dd 100644
--- a/numpy/core/tests/test_multiarray.py
+++ b/numpy/core/tests/test_multiarray.py
@@ -929,25 +929,24 @@ class TestArgmax(TestCase):
         ([complex(1, 0), complex(0, 2), complex(0, 1)], 0),
         ([complex(1, 0), complex(0, 2), complex(1, 1)], 2),
 
-        # Fails on 32-bit systems (haven't tested 64-bit) due to y2.038k bug
-        #([np.datetime64('1923-04-14T12:43:12'),
-        #  np.datetime64('1994-06-21T14:43:15'),
-        #  np.datetime64('2001-10-15T04:10:32'),
-        #  np.datetime64('1995-11-25T16:02:16'),
-        #  np.datetime64('2005-01-04T03:14:12'),
-        #  np.datetime64('2041-12-03T14:05:03')], 5),
+        ([np.datetime64('1923-04-14T12:43:12'),
+          np.datetime64('1994-06-21T14:43:15'),
+          np.datetime64('2001-10-15T04:10:32'),
+          np.datetime64('1995-11-25T16:02:16'),
+          np.datetime64('2005-01-04T03:14:12'),
+          np.datetime64('2041-12-03T14:05:03')], 5),
         ([np.datetime64('1935-09-14T04:40:11'),
           np.datetime64('1949-10-12T12:32:11'),
           np.datetime64('2010-01-03T05:14:12'),
           np.datetime64('2015-11-20T12:20:59'),
           np.datetime64('1932-09-23T10:10:13'),
           np.datetime64('2014-10-10T03:50:30')], 3),
-        #([np.datetime64('2059-03-14T12:43:12'),
-        #  np.datetime64('1996-09-21T14:43:15'),
-        #  np.datetime64('2001-10-15T04:10:32'),
-        #  np.datetime64('2022-12-25T16:02:16'),
-        #  np.datetime64('1963-10-04T03:14:12'),
-        #  np.datetime64('2013-05-08T18:15:23')], 0),
+        ([np.datetime64('2059-03-14T12:43:12'),
+          np.datetime64('1996-09-21T14:43:15'),
+          np.datetime64('2001-10-15T04:10:32'),
+          np.datetime64('2022-12-25T16:02:16'),
+          np.datetime64('1963-10-04T03:14:12'),
+          np.datetime64('2013-05-08T18:15:23')], 0),
 
         ([timedelta(days=5, seconds=14), timedelta(days=2, seconds=35),
           timedelta(days=-1, seconds=23)], 0),
@@ -998,25 +997,24 @@ class TestArgmin(TestCase):
         ([complex(1, 0), complex(0, 2), complex(0, 1)], 2),
         ([complex(1, 0), complex(0, 2), complex(1, 1)], 1),
 
-        # Fails on 32-bit systems (haven't tested 64-bit) due to y2.038k bug
-        #([np.datetime64('1923-04-14T12:43:12'),
-        #  np.datetime64('1994-06-21T14:43:15'),
-        #  np.datetime64('2001-10-15T04:10:32'),
-        #  np.datetime64('1995-11-25T16:02:16'),
-        #  np.datetime64('2005-01-04T03:14:12'),
-        # np.datetime64('2041-12-03T14:05:03')], 0),
+        ([np.datetime64('1923-04-14T12:43:12'),
+          np.datetime64('1994-06-21T14:43:15'),
+          np.datetime64('2001-10-15T04:10:32'),
+          np.datetime64('1995-11-25T16:02:16'),
+          np.datetime64('2005-01-04T03:14:12'),
+          np.datetime64('2041-12-03T14:05:03')], 0),
         ([np.datetime64('1935-09-14T04:40:11'),
           np.datetime64('1949-10-12T12:32:11'),
           np.datetime64('2010-01-03T05:14:12'),
           np.datetime64('2014-11-20T12:20:59'),
           np.datetime64('2015-09-23T10:10:13'),
           np.datetime64('1932-10-10T03:50:30')], 5),
-        #([np.datetime64('2059-03-14T12:43:12'),
-        #  np.datetime64('1996-09-21T14:43:15'),
-        #  np.datetime64('2001-10-15T04:10:32'),
-        #  np.datetime64('2022-12-25T16:02:16'),
-        #  np.datetime64('1963-10-04T03:14:12'),
-        #  np.datetime64('2013-05-08T18:15:23')], 4),
+        ([np.datetime64('2059-03-14T12:43:12'),
+          np.datetime64('1996-09-21T14:43:15'),
+          np.datetime64('2001-10-15T04:10:32'),
+          np.datetime64('2022-12-25T16:02:16'),
+          np.datetime64('1963-10-04T03:14:12'),
+          np.datetime64('2013-05-08T18:15:23')], 4),
 
         ([timedelta(days=5, seconds=14), timedelta(days=2, seconds=35),
           timedelta(days=-1, seconds=23)], 2),
diff --git a/numpy/core/tests/test_umath.py b/numpy/core/tests/test_umath.py
index 9c5ff8eef..e6e1e593f 100644
--- a/numpy/core/tests/test_umath.py
+++ b/numpy/core/tests/test_umath.py
@@ -470,6 +470,11 @@ class TestMaximum(TestCase):
             out  = np.array([nan, nan, nan], dtype=np.complex)
             assert_equal(np.maximum(arg1, arg2), out)
 
+    def test_object_array(self):
+        arg1 = np.arange(5, dtype=np.object)
+        arg2 = arg1 + 1
+        assert_equal(np.maximum(arg1, arg2), arg2)
+
 
 class TestMinimum(TestCase):
     def test_reduce(self):
@@ -512,6 +517,11 @@ class TestMinimum(TestCase):
             out  = np.array([nan, nan, nan], dtype=np.complex)
             assert_equal(np.minimum(arg1, arg2), out)
 
+    def test_object_array(self):
+        arg1 = np.arange(5, dtype=np.object)
+        arg2 = arg1 + 1
+        assert_equal(np.minimum(arg1, arg2), arg1)
+
 
 class TestFmax(TestCase):
     def test_reduce(self):