Auto merge of numpy#6206 - jaimefrio:searchsorted_ndarray, r=njsmith

MANT: searchsorted should return base ndarrays always

numpy/core/src/multiarray/item_selection.c

@@ -1722,7 +1722,7 @@ PyArray_SearchSorted(PyArrayObject *op1, PyObject *op2,
     }
 
     /* ret is a contiguous array of intp type to hold returned indexes */
-    ret = (PyArrayObject *)PyArray_New(Py_TYPE(ap2), PyArray_NDIM(ap2),
+    ret = (PyArrayObject *)PyArray_New(&PyArray_Type, PyArray_NDIM(ap2),
                                        PyArray_DIMS(ap2), NPY_INTP,
                                        NULL, NULL, 0, 0, (PyObject *)ap2);
     if (ret == NULL) {

numpy/core/tests/test_multiarray.py

@@ -1526,6 +1526,18 @@ def test_searchsorted_with_sorter(self):
         b = a.searchsorted(a, 'r', s)
         assert_equal(b, out + 1)
 
+    def test_searchsorted_return_type(self):
+        # Functions returning indices should always return base ndarrays
+        class A(np.ndarray):
+            pass
+        a = np.arange(5).view(A)
+        b = np.arange(1, 3).view(A)
+        s = np.arange(5).view(A)
+        assert_(not isinstance(a.searchsorted(b, 'l'), A))
+        assert_(not isinstance(a.searchsorted(b, 'r'), A))
+        assert_(not isinstance(a.searchsorted(b, 'l', s), A))
+        assert_(not isinstance(a.searchsorted(b, 'r', s), A))
+
     def test_argpartition_out_of_range(self):
         # Test out of range values in kth raise an error, gh-5469
         d = np.arange(10)

numpy/lib/tests/test_function_base.py

@@ -913,6 +913,15 @@ def test_casting_error(self):
         x, bins = bins, x
         assert_raises(TypeError, digitize, x, bins)
 
+    def test_return_type(self):
+        # Functions returning indices should always return base ndarrays
+        class A(np.ndarray):
+            pass
+        a = np.arange(5).view(A)
+        b = np.arange(1, 3).view(A)
+        assert_(not isinstance(digitize(b, a, False), A))
+        assert_(not isinstance(digitize(b, a, True), A))
+
 
 class TestUnwrap(TestCase):