Simplify implementation and rename public function

Author: pablogsal

Include/internal/pycore_suggestions.h

@@ -7,7 +7,7 @@
 #  error "this header requires Py_BUILD_CORE define"
 #endif
 
-int _Py_offer_suggestions(PyAttributeErrorObject* exception_value);
+int _Py_offer_suggestions_for_attribute_error(PyAttributeErrorObject* exception_value);
 
 
 #endif /* !Py_INTERNAL_SUGGESTIONS_H */

Python/pythonrun.c

@@ -1011,7 +1011,7 @@ PyErr_Display(PyObject *exception, PyObject *value, PyObject *tb)
     }
 
     if (PyErr_GivenExceptionMatches(exception, PyExc_AttributeError) &&
-        _Py_offer_suggestions((PyAttributeErrorObject*) value) != 0) {
+        _Py_offer_suggestions_for_attribute_error((PyAttributeErrorObject*) value) != 0) {
              PyErr_Clear();
     }
     _PyErr_Display(file, exception, value, tb);

Python/suggestions.c

@@ -164,51 +164,48 @@ calculate_suggestions(PyObject* dir,
 }
 
 int
-_Py_offer_suggestions(PyAttributeErrorObject* exc) {
+_Py_offer_suggestions_for_attribute_error(PyAttributeErrorObject* exc) {
     int return_val = 0;
 
     PyObject* name = exc->name;
     PyObject* v = exc->obj;
 
+    // Aboirt if we don't have an attribute name or we have an invalid one
     if ((name == NULL) || (v == NULL) || !PyUnicode_CheckExact(name)) {
-        return 0;
+        return -1;
     }
 
     PyObject* oldexceptionvalue = NULL;
     Py_ssize_t nargs = PyTuple_GET_SIZE(exc->args);
-
-    if (nargs > 1) {
-        // Exceptions with more than 1 value in args are not
-        // formatted using args, so no need to make a new suggestion.
-        return 0;
-    }
-
-    if (nargs == 1) {
-        oldexceptionvalue = PyTuple_GET_ITEM(exc->args, 0);
-        Py_INCREF(oldexceptionvalue);
-    } 
-
-    // Check that the the message is an uncode objects that we can use,
-    // and if not, create an empty value.
-    if (!oldexceptionvalue || !PyUnicode_CheckExact(oldexceptionvalue)) {
-        Py_XDECREF(oldexceptionvalue);
-        oldexceptionvalue = PyUnicode_New(0, 0);
+    switch (nargs) {
+        case 0:
+            oldexceptionvalue = PyUnicode_New(0, 0);
+            break;
+        case 1:
+            oldexceptionvalue = PyTuple_GET_ITEM(exc->args, 0);
+            Py_INCREF(oldexceptionvalue);
+            // Check that the the message is an uncode objects that we can use.
+            if (!PyUnicode_CheckExact(oldexceptionvalue)) {
+                return_val = -1;
+                goto exit;
+            }
+            break;
+        default:
+            // Exceptions with more than 1 value in args are not
+            // formatted using args, so no need to make a new suggestion.
+            return 0;
     }
 
-    if (Py_EnterRecursiveCall(" while getting the __dir__ of an object")) {
-        return_val = -1;
+    PyObject* dir = PyObject_Dir(v);
+    if (!dir) {
         goto exit;
     }
-    PyObject* dir = PyObject_Dir(v);
-    Py_LeaveRecursiveCall();
 
-    PyObject* newexceptionvalue = NULL;
-    if (dir) {
-        newexceptionvalue = calculate_suggestions(dir, name, oldexceptionvalue);
-        Py_DECREF(dir);
-    }
+    PyObject* newexceptionvalue = calculate_suggestions(dir, name, oldexceptionvalue);
+    Py_DECREF(dir);
 
     if (newexceptionvalue == NULL) {
+        // We did't find a suggestion :(
         goto exit;
     }