MAINT: add deprecation warnings for NPY_CHAR usage

4 files changed, 44 insertions, 1 deletions

diff --git a/numpy/core/include/numpy/ndarraytypes.h b/numpy/core/include/numpy/ndarraytypes.h
index 7f6fe6524..e0df189f9 100644
--- a/numpy/core/include/numpy/ndarraytypes.h
+++ b/numpy/core/include/numpy/ndarraytypes.h
@@ -15,7 +15,17 @@
         #define NPY_ALLOW_THREADS 0
 #endif
 
+#ifndef __has_extension
+#define __has_extension(x) 0
+#endif
 
+#if !defined(_NPY_NO_DEPRECATIONS) && \
+    ((defined(__GNUC__)&& __GNUC__ >= 6) || \
+     __has_extension(attribute_deprecated_with_message))
+#define NPY_ATTR_DEPRECATE(text) __attribute__ ((deprecated (text)))
+#else
+#define NPY_ATTR_DEPRECATE(text)
+#endif
 
 /*
  * There are several places in the code where an array of dimensions
@@ -71,12 +81,15 @@ enum NPY_TYPES {    NPY_BOOL=0,
 
                     NPY_NTYPES,
                     NPY_NOTYPE,
-                    NPY_CHAR,      /* special flag */
+                    NPY_CHAR NPY_ATTR_DEPRECATE("Use NPY_STRING"),
                     NPY_USERDEF=256,  /* leave room for characters */
 
                     /* The number of types not including the new 1.6 types */
                     NPY_NTYPES_ABI_COMPATIBLE=21
 };
+#ifdef _MSC_VER
+#pragma deprecated(NPY_CHAR)
+#endif
 
 /* basetype array priority */
 #define NPY_PRIORITY 0.0
diff --git a/numpy/core/src/multiarray/arraytypes.c.src b/numpy/core/src/multiarray/arraytypes.c.src
index 49d6ae1d2..b11134305 100644
--- a/numpy/core/src/multiarray/arraytypes.c.src
+++ b/numpy/core/src/multiarray/arraytypes.c.src
@@ -6,6 +6,7 @@
 
 #define NPY_NO_DEPRECATED_API NPY_API_VERSION
 #define _MULTIARRAYMODULE
+#define _NPY_NO_DEPRECATIONS /* for NPY_CHAR */
 
 #include "numpy/npy_common.h"
 #include "numpy/arrayobject.h"
@@ -4415,6 +4416,17 @@ PyArray_DescrFromType(int type)
         return NULL;
     }
     else if ((type == NPY_CHAR) || (type == NPY_CHARLTR)) {
+        if (type == NPY_CHAR) {
+            /*
+             * warning added 2017-04-25, 1.13
+             * deprecated in 1.7
+             * */
+            if (DEPRECATE("The NPY_CHAR type_num is deprecated. "
+                          "Please port your code to use "
+                          "NPY_STRING instead.") < 0) {
+                return NULL;
+            }
+        }
         ret = PyArray_DescrNew(_builtin_descrs[NPY_STRING]);
         if (ret == NULL) {
             return NULL;
diff --git a/numpy/core/src/multiarray/multiarray_tests.c.src b/numpy/core/src/multiarray/multiarray_tests.c.src
index 45092dc0c..de05cc280 100644
--- a/numpy/core/src/multiarray/multiarray_tests.c.src
+++ b/numpy/core/src/multiarray/multiarray_tests.c.src
@@ -1,6 +1,7 @@
 /* -*-c-*- */
 #define NPY_NO_DEPRECATED_API NPY_API_VERSION
 #include <Python.h>
+#define _NPY_NO_DEPRECATIONS /* for NPY_CHAR */
 #include "numpy/arrayobject.h"
 #include "mem_overlap.h"
 #include "npy_extint128.h"
@@ -608,6 +609,13 @@ incref_elide_l(PyObject *dummy, PyObject *args)
     return res;
 }
 
+/* used to test NPY_CHAR usage emits deprecation warning */
+static PyObject*
+npy_char_deprecation(PyObject* NPY_UNUSED(self), PyObject* NPY_UNUSED(args))
+{
+    PyArray_Descr * descr = PyArray_DescrFromType(NPY_CHAR);
+    return (PyObject *)descr;
+}
 
 #if !defined(NPY_PY3K)
 static PyObject *
@@ -1576,6 +1584,9 @@ static PyMethodDef Multiarray_TestsMethods[] = {
     {"incref_elide_l",
         incref_elide_l,
         METH_VARARGS, NULL},
+    {"npy_char_deprecation",
+        npy_char_deprecation,
+        METH_NOARGS, NULL},
 #if !defined(NPY_PY3K)
     {"test_int_subclass",
         int_subclass,
diff --git a/numpy/core/tests/test_deprecations.py b/numpy/core/tests/test_deprecations.py
index 46b2c79aa..2f1cedd9b 100644
--- a/numpy/core/tests/test_deprecations.py
+++ b/numpy/core/tests/test_deprecations.py
@@ -421,5 +421,12 @@ class TestClassicIntDivision(_DeprecationTestCase):
                 dt2 = dt1
 
 
+class TestNPY_CHAR(_DeprecationTestCase):
+    def test_npy_char_deprecation(self):
+        from numpy.core.multiarray_tests import npy_char_deprecation
+        self.assert_deprecated(npy_char_deprecation)
+        assert_(npy_char_deprecation() == 'S1')
+
+
 if __name__ == "__main__":
     run_module_suite()