Issue #13959: Simplify imp.reload() by relying on a module's

__loader__.

Since import now sets __loader__ on all modules it creates and
imp.reload() already relied on the attribute for modules that import
didn't create, the only potential compatibility issue is if people
were deleting the attribute on modules and expecting imp.reload() to
continue to work.

1 files changed, 10 insertions, 34 deletions

diff --git a/Python/import.c b/Python/import.c
index a930382..747b0dd 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -153,7 +153,6 @@ static const struct filedescr _PyImport_StandardFiletab[] = {
 };
 
 static PyObject *initstr = NULL;
-_Py_IDENTIFIER(__path__);
 
 /* Initialize things */
 
@@ -3106,12 +3105,12 @@ PyImport_ReloadModule(PyObject *m)
     PyInterpreterState *interp = PyThreadState_Get()->interp;
     PyObject *modules_reloading = interp->modules_reloading;
     PyObject *modules = PyImport_GetModuleDict();
-    PyObject *path_list = NULL, *loader = NULL, *existing_m = NULL;
-    PyObject *name, *bufobj, *subname;
+    PyObject *loader = NULL, *existing_m = NULL;
+    PyObject *name;
     Py_ssize_t subname_start;
-    struct filedescr *fdp;
-    FILE *fp = NULL;
     PyObject *newm = NULL;
+    _Py_IDENTIFIER(__loader__);
+    _Py_IDENTIFIER(load_module);
 
     if (modules_reloading == NULL) {
         Py_FatalError("PyImport_ReloadModule: "
@@ -3149,51 +3148,28 @@ PyImport_ReloadModule(PyObject *m)
 
     subname_start = PyUnicode_FindChar(name, '.', 0,
                                        PyUnicode_GET_LENGTH(name), -1);
-    if (subname_start == -1) {
-        Py_INCREF(name);
-        subname = name;
-    }
-    else {
+    if (subname_start != -1) {
         PyObject *parentname, *parent;
-        Py_ssize_t len;
         parentname = PyUnicode_Substring(name, 0, subname_start);
         if (parentname == NULL) {
             goto error;
         }
         parent = PyDict_GetItem(modules, parentname);
+        Py_XDECREF(parent);
         if (parent == NULL) {
             PyErr_Format(PyExc_ImportError,
                 "reload(): parent %R not in sys.modules",
                  parentname);
-            Py_DECREF(parentname);
             goto error;
         }
-        Py_DECREF(parentname);
-        path_list = _PyObject_GetAttrId(parent, &PyId___path__);
-        if (path_list == NULL)
-            PyErr_Clear();
-        subname_start++;
-        len = PyUnicode_GET_LENGTH(name) - (subname_start + 1);
-        subname = PyUnicode_Substring(name, subname_start, len);
     }
-    if (subname == NULL)
-        goto error;
-    fdp = find_module(name, subname, path_list,
-                      &bufobj, &fp, &loader);
-    Py_DECREF(subname);
-    Py_XDECREF(path_list);
 
-    if (fdp == NULL) {
-        Py_XDECREF(loader);
+    loader = _PyObject_GetAttrId(m, &PyId___loader__);
+    if (loader == NULL) {
         goto error;
     }
-
-    newm = load_module(name, fp, bufobj, fdp->type, loader);
-    Py_XDECREF(bufobj);
-    Py_XDECREF(loader);
-
-    if (fp)
-        fclose(fp);
+    newm = _PyObject_CallMethodId(loader, &PyId_load_module, "O", name);
+    Py_DECREF(loader);
     if (newm == NULL) {
         /* load_module probably removed name from modules because of
          * the error.  Put back the original module object.  We're