pythongh-108732: include comprehension locals in frame.f_locals

Author: carljm

Lib/test/test_listcomps.py

@@ -596,6 +596,15 @@ def test_exception_in_post_comp_call(self):
         """
         self._check_in_scopes(code, {"value": [1, None]})
 
+    def test_frame_locals(self):
+        code = """
+            import sys
+            [locs := sys._getframe().f_locals for a in [0]]
+            val = locs["a"]
+        """
+        # assignment expression in comprehension is a SyntaxError in a class body
+        self._check_in_scopes(code, {"val": 0}, scopes=["module", "function"])
+
 
 __test__ = {'doctests' : doctests}
 

Objects/frameobject.c

@@ -25,10 +25,16 @@ static PyMemberDef frame_memberlist[] = {
 static PyObject *
 frame_getlocals(PyFrameObject *f, void *closure)
 {
-    if (PyFrame_FastToLocalsWithError(f) < 0)
-        return NULL;
-    PyObject *locals = f->f_frame->f_locals;
-    return Py_NewRef(locals);
+    if (f == NULL) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    assert(!_PyFrame_IsIncomplete(f->f_frame));
+    PyObject *locals = _PyFrame_GetLocals(f->f_frame, 1);
+    if (locals) {
+        f->f_fast_as_locals = 1;
+    }
+    return locals;
 }
 
 int
@@ -1342,11 +1348,11 @@ PyFrame_GetVarString(PyFrameObject *frame, const char *name)
 int
 PyFrame_FastToLocalsWithError(PyFrameObject *f)
 {
-    assert(!_PyFrame_IsIncomplete(f->f_frame));
     if (f == NULL) {
         PyErr_BadInternalCall();
         return -1;
     }
+    assert(!_PyFrame_IsIncomplete(f->f_frame));
     int err = _PyFrame_FastToLocalsWithError(f->f_frame);
     if (err == 0) {
         f->f_fast_as_locals = 1;