Partial 3.8 async "for" fixes

uncompyle6/parsers/parse37base.py

@@ -584,6 +584,21 @@ class Python37BaseParser(PythonParser):
                 """
                 self.add_unique_doc_rules(rules_str, customize)
 
+            elif opname == "GET_ANEXT":
+                self.addRule(
+                    """
+                    func_async_prefix   ::= _come_froms SETUP_FINALLY GET_ANEXT LOAD_CONST YIELD_FROM POP_BLOCK
+                    func_async_middle   ::= JUMP_FORWARD COME_FROM_EXCEPT
+                                            DUP_TOP LOAD_GLOBAL COMPARE_OP POP_JUMP_IF_TRUE
+                    list_afor2          ::= func_async_prefix
+                                            store list_iter
+                                            JUMP_BACK COME_FROM_FINALLY
+                                            END_ASYNC_FOR
+                   """,
+                    nop_func,
+                )
+                custom_ops_processed.add(opname)
+
             elif opname == "FORMAT_VALUE_ATTR":
                 rules_str = """
                 expr              ::= formatted_value2

uncompyle6/parsers/parse38.py

@@ -75,6 +75,11 @@ class Python38Parser(Python37Parser):
                                COME_FROM_FINALLY
                                END_ASYNC_FOR
 
+       genexpr_func_async  ::= LOAD_FAST func_async_prefix
+                               store comp_iter
+                               JUMP_BACK COME_FROM_FINALLY
+                               END_ASYNC_FOR
+
         # FIXME: come froms after the else_suite or END_ASYNC_FOR distinguish which of
         # for / forelse is used. Add come froms and check of add up control-flow detection phase.
         async_forelse_stmt38 ::= expr

uncompyle6/semantics/pysource.py

@@ -1179,10 +1179,22 @@ class SourceWalker(GenericASTTraversal, object):
             code_index = -6
             if self.version > (3, 6):
                 # Python 3.7+ adds optional "come_froms" at node[0]
-                iter_index = 4
+                if node[0].kind in ("load_closure", "load_genexpr") and self.version >= (3, 8):
+                    is_lambda = self.is_lambda
+                    if node[0].kind == "load_genexpr":
+                        self.is_lambda = False
+                        self.closure_walk(node, collection_index=4)
+                    self.closure_walk(node, collection_index=4)
+                    self.is_lambda = is_lambda
+                else:
+                    code_index = -6
+                    iter_index = 4 if self.version < (3, 8) else 3
+                    self.comprehension_walk(node, iter_index=iter_index, code_index=code_index)
+                    pass
+                pass
         else:
             code_index = -5
-        self.comprehension_walk(node, iter_index=iter_index, code_index=code_index)
+            self.comprehension_walk(node, iter_index=iter_index, code_index=code_index)
         self.write(")")
         self.prune()
 
@@ -1421,7 +1433,8 @@ class SourceWalker(GenericASTTraversal, object):
         store = ast[3]
         collection = node[collection_index]
 
-        n = ast[4]
+        iter_index = 3 if ast == "genexpr_func_async" else 4
+        n = ast[iter_index]
         list_if = None
         assert n == "comp_iter"