Merge pull request #13049 from mattip/remove-buffer-check

MAINT: remove undocumented __buffer__ attribute lookup

4 files changed, 8 insertions, 29 deletions

diff --git a/doc/release/1.17.0-notes.rst b/doc/release/1.17.0-notes.rst
index d8ece4244..262db18ef 100644
--- a/doc/release/1.17.0-notes.rst
+++ b/doc/release/1.17.0-notes.rst
@@ -52,6 +52,13 @@ zero::
    >>> np.zeros(10)//1
    array([0., 0., 0., 0., 0., 0., 0., 0., 0., 0.])
 
+Do not lookup ``__buffer__`` attribute in `numpy.frombuffer`
+------------------------------------------------------------
+
+Looking up ``__buffer__`` attribute in `numpy.frombuffer` was undocumented and
+non-functional. This code was removed. If needed, use
+``frombuffer(memoryview(obj), ...)`` instead.
+
 C API changes
 =============
 
diff --git a/numpy/core/src/multiarray/ctors.c b/numpy/core/src/multiarray/ctors.c
index b2e329d45..3772231c4 100644
--- a/numpy/core/src/multiarray/ctors.c
+++ b/numpy/core/src/multiarray/ctors.c
@@ -3693,32 +3693,12 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
         Py_DECREF(type);
         return NULL;
     }
-    if (Py_TYPE(buf)->tp_as_buffer == NULL
-#if defined(NPY_PY3K)
-        || Py_TYPE(buf)->tp_as_buffer->bf_getbuffer == NULL
-#else
-        || (Py_TYPE(buf)->tp_as_buffer->bf_getwritebuffer == NULL
-            && Py_TYPE(buf)->tp_as_buffer->bf_getreadbuffer == NULL)
-#endif
-        ) {
-        PyObject *newbuf;
-        newbuf = PyObject_GetAttr(buf, npy_ma_str_buffer);
-        if (newbuf == NULL) {
-            Py_DECREF(type);
-            return NULL;
-        }
-        buf = newbuf;
-    }
-    else {
-        Py_INCREF(buf);
-    }
 
 #if defined(NPY_PY3K)
     if (PyObject_GetBuffer(buf, &view, PyBUF_WRITABLE|PyBUF_SIMPLE) < 0) {
         writeable = 0;
         PyErr_Clear();
         if (PyObject_GetBuffer(buf, &view, PyBUF_SIMPLE) < 0) {
-            Py_DECREF(buf);
             Py_DECREF(type);
             return NULL;
         }
@@ -3738,7 +3718,6 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
         writeable = 0;
         PyErr_Clear();
         if (PyObject_AsReadBuffer(buf, (void *)&data, &ts) == -1) {
-            Py_DECREF(buf);
             Py_DECREF(type);
             return NULL;
         }
@@ -3749,7 +3728,6 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
         PyErr_Format(PyExc_ValueError,
                      "offset must be non-negative and no greater than buffer "\
                      "length (%" NPY_INTP_FMT ")", (npy_intp)ts);
-        Py_DECREF(buf);
         Py_DECREF(type);
         return NULL;
     }
@@ -3763,7 +3741,6 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
             PyErr_SetString(PyExc_ValueError,
                             "buffer size must be a multiple"\
                             " of element size");
-            Py_DECREF(buf);
             Py_DECREF(type);
             return NULL;
         }
@@ -3774,7 +3751,6 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
             PyErr_SetString(PyExc_ValueError,
                             "buffer is smaller than requested"\
                             " size");
-            Py_DECREF(buf);
             Py_DECREF(type);
             return NULL;
         }
@@ -3784,7 +3760,6 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
             &PyArray_Type, type,
             1, &n, NULL, data,
             NPY_ARRAY_DEFAULT, NULL, buf);
-    Py_DECREF(buf);
     if (ret == NULL) {
         return NULL;
     }
diff --git a/numpy/core/src/multiarray/multiarraymodule.c b/numpy/core/src/multiarray/multiarraymodule.c
index ce6a3870f..1b825d318 100644
--- a/numpy/core/src/multiarray/multiarraymodule.c
+++ b/numpy/core/src/multiarray/multiarraymodule.c
@@ -4492,7 +4492,6 @@ NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array = NULL;
 NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array_prepare = NULL;
 NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array_wrap = NULL;
 NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array_finalize = NULL;
-NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_buffer = NULL;
 NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_ufunc = NULL;
 NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_wrapped = NULL;
 NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_order = NULL;
@@ -4509,7 +4508,6 @@ intern_strings(void)
     npy_ma_str_array_prepare = PyUString_InternFromString("__array_prepare__");
     npy_ma_str_array_wrap = PyUString_InternFromString("__array_wrap__");
     npy_ma_str_array_finalize = PyUString_InternFromString("__array_finalize__");
-    npy_ma_str_buffer = PyUString_InternFromString("__buffer__");
     npy_ma_str_ufunc = PyUString_InternFromString("__array_ufunc__");
     npy_ma_str_wrapped = PyUString_InternFromString("__wrapped__");
     npy_ma_str_order = PyUString_InternFromString("order");
@@ -4521,7 +4519,7 @@ intern_strings(void)
 
     return npy_ma_str_array && npy_ma_str_array_prepare &&
            npy_ma_str_array_wrap && npy_ma_str_array_finalize &&
-           npy_ma_str_buffer && npy_ma_str_ufunc && npy_ma_str_wrapped &&
+           npy_ma_str_ufunc && npy_ma_str_wrapped &&
            npy_ma_str_order && npy_ma_str_copy && npy_ma_str_dtype &&
            npy_ma_str_ndmin && npy_ma_str_axis1 && npy_ma_str_axis2;
 }
diff --git a/numpy/core/src/multiarray/multiarraymodule.h b/numpy/core/src/multiarray/multiarraymodule.h
index 60a3965c9..6d33c3295 100644
--- a/numpy/core/src/multiarray/multiarraymodule.h
+++ b/numpy/core/src/multiarray/multiarraymodule.h
@@ -5,7 +5,6 @@ NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array;
 NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array_prepare;
 NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array_wrap;
 NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array_finalize;
-NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_buffer;
 NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_ufunc;
 NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_wrapped;
 NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_order;