numpy
diff --git a/‎numpy/_core/src/multiarray/scalartypes.c.src
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+25-4Lines changed: 25 additions & 4 deletions b/‎numpy/_core/src/multiarray/scalartypes.c.src
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+25-4Lines changed: 25 additions & 4 deletions
diff --git a/‎numpy/_core/tests/test_multiarray.py
Copy file name to clipboardExpand all lines: numpy/_core/tests/test_multiarray.py
+12Lines changed: 12 additions & 0 deletions b/‎numpy/_core/tests/test_multiarray.py
Copy file name to clipboardExpand all lines: numpy/_core/tests/test_multiarray.py
+12Lines changed: 12 additions & 0 deletions
@@ -194,15 +194,30 @@ find_binary_operation_path(
             PyLong_CheckExact(other) ||
             PyFloat_CheckExact(other) ||
             PyComplex_CheckExact(other) ||
-            PyBool_Check(other)) {
+            PyBool_Check(other) ||
+            PyArray_Check(other)) {
         /*
          * The other operand is ready for the operation already.  Must pass on
          * on float/long/complex mainly for weak promotion (NEP 50).
          */
-        Py_INCREF(other);
-        *other_op = other;
+        *other_op = Py_NewRef(other);
         return 0;
     }
+    /*
+     * If other has __array_ufunc__ we promise to use the ufunc and don't need
+     * to worry about recursion (yet).  Possible `__array_ufunc__ = None`
+     * deferral was already dealt with here.
+     * It may be nice to avoid double lookup in `BINOP_GIVE_UP_IF_NEEDED`.
+     */
+    PyObject *attr = PyArray_LookupSpecial(other, npy_interned_str.array_ufunc);
+    if (attr != NULL) {
+        Py_DECREF(attr);
+        *other_op = Py_NewRef(other);
+        return 0;
+    }
+    else if (PyErr_Occurred()) {
+        PyErr_Clear(); /* TODO[gh-14801]: propagate crashes during attribute access? */
+    }
 
     /*
      * Now check `other`.  We want to know whether it is an object scalar
@@ -216,7 +231,13 @@ find_binary_operation_path(
     }
 
     if (!was_scalar || PyArray_DESCR(arr)->type_num != NPY_OBJECT) {
-        /* The array is OK for usage and we can simply forward it
+        /* 
+         * The array is OK for usage and we can simply forward it.  There
+         * is a theoretical subtlety here:  If the other object implements
+         * `__array_wrap__`, we may ignore that.  However, this only matters
+         * if the other object has the identical `__array_priority__` and
+         * additionally already deferred back to us.
+         * (`obj + scalar` and `scalar + obj` are not symmetric.)
          *
          * NOTE: Future NumPy may need to distinguish scalars here, one option
          *       could be marking the array.
 
@@ -4025,6 +4025,18 @@ class LowPriority(np.ndarray):
         assert res.shape == (3,)
         assert res[0] == 'result'
 
+    @pytest.mark.parametrize("scalar", [
+            np.longdouble(1), np.timedelta64(120,'m')])
+    @pytest.mark.parametrize("op", [operator.add, operator.xor])
+    def test_scalar_binop_guarantees_ufunc(self, scalar, op):
+        # Test that __array_ufunc__ will always cause ufunc use even when
+        # we have to protect some other calls from recursing (see gh-26904).
+        class SomeClass:
+            def __array_ufunc__(self, ufunc, method, *inputs, **kw):
+                return "result"
+
+        assert SomeClass() + np.longdouble(1) == "result"
+        assert np.longdouble(1) + SomeClass() == "result"
 
     def test_ufunc_override_normalize_signature(self):
         # gh-5674