Merge pull request #8971 from juliantaylor/uninitialized-empty

BUG: do not change size 0 description when viewing data
numpy · Apr 23, 2017 · 4408f74 · 4408f74
2 parents 704c9cc + 6373dc0
commit 4408f74
Show file tree

Hide file tree

Showing 2 changed files with 6 additions and 1 deletion.
diff --git a/numpy/core/src/multiarray/ctors.c b/numpy/core/src/multiarray/ctors.c
@@ -937,7 +937,9 @@ PyArray_NewFromDescr_int(PyTypeObject *subtype, PyArray_Descr *descr, int nd,
             PyErr_SetString(PyExc_TypeError, "Empty data-type");
             Py_DECREF(descr);
             return NULL;
-        } else if (PyDataType_ISSTRING(descr) && !allow_emptystring) {
+        }
+        else if (PyDataType_ISSTRING(descr) && !allow_emptystring &&
+                 data == NULL) {
             PyArray_DESCR_REPLACE(descr);
             if (descr == NULL) {
                 return NULL;

diff --git a/numpy/core/tests/test_multiarray.py b/numpy/core/tests/test_multiarray.py
@@ -1073,6 +1073,9 @@ def test_zero_width_string(self):
         xx = x['S'].reshape((2, 2))
         assert_equal(xx.itemsize, 0)
         assert_equal(xx, [[b'', b''], [b'', b'']])
+        # check for no uninitialized memory due to viewing S0 array
+        assert_equal(xx[:].dtype, xx.dtype)
+        assert_array_equal(eval(repr(xx), dict(array=np.array)), xx)
 
         b = io.BytesIO()
         np.save(b, xx)