bpo-38530: Offer suggestions on NameError (GH-25397)
When printing NameError raised by the interpreter, PyErr_Display
will offer suggestions of simmilar variable names in the function that the exception
was raised from:
>>> schwarzschild_black_hole = None
>>> schwarschild_black_hole
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'schwarschild_black_hole' is not defined. Did you mean: schwarzschild_black_hole?diff --git a/Objects/exceptions.c b/Objects/exceptions.c
index 4bb4153..9916ce8 100644
--- a/Objects/exceptions.c
+++ b/Objects/exceptions.c
@@ -1326,8 +1326,69 @@ SimpleExtendsException(PyExc_RuntimeError, NotImplementedError,
/*
* NameError extends Exception
*/
-SimpleExtendsException(PyExc_Exception, NameError,
- "Name not found globally.");
+
+static int
+NameError_init(PyNameErrorObject *self, PyObject *args, PyObject *kwds)
+{
+ static char *kwlist[] = {"name", NULL};
+ PyObject *name = NULL;
+
+ if (BaseException_init((PyBaseExceptionObject *)self, args, NULL) == -1) {
+ return -1;
+ }
+
+ PyObject *empty_tuple = PyTuple_New(0);
+ if (!empty_tuple) {
+ return -1;
+ }
+ if (!PyArg_ParseTupleAndKeywords(empty_tuple, kwds, "|$O:NameError", kwlist,
+ &name)) {
+ Py_DECREF(empty_tuple);
+ return -1;
+ }
+ Py_DECREF(empty_tuple);
+
+ Py_XINCREF(name);
+ Py_XSETREF(self->name, name);
+
+ return 0;
+}
+
+static int
+NameError_clear(PyNameErrorObject *self)
+{
+ Py_CLEAR(self->name);
+ return BaseException_clear((PyBaseExceptionObject *)self);
+}
+
+static void
+NameError_dealloc(PyNameErrorObject *self)
+{
+ _PyObject_GC_UNTRACK(self);
+ NameError_clear(self);
+ Py_TYPE(self)->tp_free((PyObject *)self);
+}
+
+static int
+NameError_traverse(PyNameErrorObject *self, visitproc visit, void *arg)
+{
+ Py_VISIT(self->name);
+ return BaseException_traverse((PyBaseExceptionObject *)self, visit, arg);
+}
+
+static PyMemberDef NameError_members[] = {
+ {"name", T_OBJECT, offsetof(PyNameErrorObject, name), 0, PyDoc_STR("name")},
+ {NULL} /* Sentinel */
+};
+
+static PyMethodDef NameError_methods[] = {
+ {NULL} /* Sentinel */
+};
+
+ComplexExtendsException(PyExc_Exception, NameError,
+ NameError, 0,
+ NameError_methods, NameError_members,
+ 0, BaseException_str, "Name not found globally.");
/*
* UnboundLocalError extends NameError