Merge pull request #13721 from eric-wieser/more_ufunc_exception_cleanup

MAINT,BUG: More ufunc exception cleanup

3 files changed, 43 insertions, 17 deletions

diff --git a/numpy/core/_exceptions.py b/numpy/core/_exceptions.py
index 1dcea6255..a1af7a78d 100644
--- a/numpy/core/_exceptions.py
+++ b/numpy/core/_exceptions.py
@@ -37,6 +37,22 @@ class UFuncTypeError(TypeError):
 
 
 @_display_as_base
+class _UFuncBinaryResolutionError(UFuncTypeError):
+    """ Thrown when a binary resolution fails """
+    def __init__(self, ufunc, dtypes):
+        super().__init__(ufunc)
+        self.dtypes = tuple(dtypes)
+        assert len(self.dtypes) == 2
+
+    def __str__(self):
+        return (
+            "ufunc {!r} cannot use operands with types {!r} and {!r}"
+        ).format(
+            self.ufunc.__name__, *self.dtypes
+        )
+
+
+@_display_as_base
 class _UFuncNoLoopError(UFuncTypeError):
     """ Thrown when a ufunc loop cannot be found """
     def __init__(self, ufunc, dtypes):
diff --git a/numpy/core/src/umath/ufunc_type_resolution.c b/numpy/core/src/umath/ufunc_type_resolution.c
index 96591ba80..58f915c6e 100644
--- a/numpy/core/src/umath/ufunc_type_resolution.c
+++ b/numpy/core/src/umath/ufunc_type_resolution.c
@@ -74,18 +74,28 @@ npy_casting_to_string(NPY_CASTING casting)
  */
 static int
 raise_binary_type_reso_error(PyUFuncObject *ufunc, PyArrayObject **operands) {
-    PyObject *errmsg;
-    const char *ufunc_name = ufunc_get_name_cstr(ufunc);
-    errmsg = PyUString_FromFormat("ufunc %s cannot use operands "
-                        "with types ", ufunc_name);
-    PyUString_ConcatAndDel(&errmsg,
-            PyObject_Repr((PyObject *)PyArray_DESCR(operands[0])));
-    PyUString_ConcatAndDel(&errmsg,
-            PyUString_FromString(" and "));
-    PyUString_ConcatAndDel(&errmsg,
-            PyObject_Repr((PyObject *)PyArray_DESCR(operands[1])));
-    PyErr_SetObject(PyExc_TypeError, errmsg);
-    Py_DECREF(errmsg);
+    static PyObject *exc_type = NULL;
+    PyObject *exc_value;
+
+    npy_cache_import(
+        "numpy.core._exceptions", "_UFuncBinaryResolutionError",
+        &exc_type);
+    if (exc_type == NULL) {
+        return -1;
+    }
+
+    /* produce an error object */
+    exc_value = Py_BuildValue(
+        "O(OO)", ufunc,
+        (PyObject *)PyArray_DESCR(operands[0]),
+        (PyObject *)PyArray_DESCR(operands[1])
+    );
+    if (exc_value == NULL){
+        return -1;
+    }
+    PyErr_SetObject(exc_type, exc_value);
+    Py_DECREF(exc_value);
+
     return -1;
 }
 
@@ -94,7 +104,7 @@ raise_binary_type_reso_error(PyUFuncObject *ufunc, PyArrayObject **operands) {
  */
 static int
 raise_no_loop_found_error(
-        PyUFuncObject *ufunc, PyArray_Descr **dtypes, npy_intp n_dtypes)
+        PyUFuncObject *ufunc, PyArray_Descr **dtypes)
 {
     static PyObject *exc_type = NULL;
     PyObject *exc_value;
@@ -109,11 +119,11 @@ raise_no_loop_found_error(
     }
 
     /* convert dtypes to a tuple */
-    dtypes_tup = PyTuple_New(n_dtypes);
+    dtypes_tup = PyTuple_New(ufunc->nargs);
     if (dtypes_tup == NULL) {
         return -1;
     }
-    for (i = 0; i < n_dtypes; ++i) {
+    for (i = 0; i < ufunc->nargs; ++i) {
         Py_INCREF(dtypes[i]);
         PyTuple_SET_ITEM(dtypes_tup, i, (PyObject *)dtypes[i]);
     }
@@ -1472,7 +1482,7 @@ PyUFunc_DefaultLegacyInnerLoopSelector(PyUFuncObject *ufunc,
         types += nargs;
     }
 
-    return raise_no_loop_found_error(ufunc, dtypes, nargs);
+    return raise_no_loop_found_error(ufunc, dtypes);
 }
 
 typedef struct {
diff --git a/numpy/core/tests/test_datetime.py b/numpy/core/tests/test_datetime.py
index f48bfdf9b..f99c0f72b 100644
--- a/numpy/core/tests/test_datetime.py
+++ b/numpy/core/tests/test_datetime.py
@@ -1825,7 +1825,7 @@ class TestDateTime(object):
         # NOTE: some of the operations may be supported
         # in the future
         with assert_raises_regex(TypeError,
-                                 "remainder cannot use operands with types"):
+                                 "'remainder' cannot use operands with types"):
             val1 % val2
 
     def test_timedelta_arange_no_dtype(self):