Add 3.7 async listcomp

test/simple_source/bug37/02_async_for_generator.py

@@ -3,3 +3,6 @@
 def make_arange(n):
     # This syntax is legal starting with Python 3.7
     return (i * 2 async for i in n)
+
+async def run(m):
+    return [i async for i in m]

uncompyle6/parsers/parse37base.py

@@ -514,7 +514,20 @@ class Python37BaseParser(PythonParser):
                                             store func_async_middle comp_iter
                                             JUMP_BACK COME_FROM
                                             POP_TOP POP_TOP POP_TOP POP_EXCEPT POP_TOP
-                    """,
+
+                    expr                ::= listcomp_async
+                    listcomp_async      ::= LOAD_LISTCOMP LOAD_STR MAKE_FUNCTION_0
+                                            expr GET_AITER CALL_FUNCTION_1
+                                            GET_AWAITABLE LOAD_CONST
+                                            YIELD_FROM
+
+                    expr                 ::= listcomp_async
+                    listcomp_async       ::= BUILD_LIST_0 LOAD_FAST func_async_prefix
+                                            store func_async_middle list_iter
+                                            JUMP_BACK COME_FROM
+                                            POP_TOP POP_TOP POP_TOP POP_EXCEPT POP_TOP
+
+                   """,
                     nop_func,
                 )
                 custom_ops_processed.add(opname)

uncompyle6/semantics/pysource.py

@@ -1221,6 +1221,8 @@ class SourceWalker(GenericASTTraversal, object):
                     n = k[0]
                     pass
                 pass
+        elif ast == "listcomp_async":
+            store = ast[3]
         else:
             assert n == "list_iter", n
 
@@ -1287,6 +1289,13 @@ class SourceWalker(GenericASTTraversal, object):
             self.preorder(n[1])
         else:
             self.preorder(n[0])
+
+        if node == "listcomp_async":
+            self.write(" async")
+            in_node_index = 3
+        else:
+            in_node_index = -3
+
         self.write(" for ")
         if comp_store:
             self.preorder(comp_store)
@@ -1295,7 +1304,7 @@ class SourceWalker(GenericASTTraversal, object):
 
         # FIXME this is all merely approximate
         self.write(" in ")
-        self.preorder(node[-3])
+        self.preorder(node[in_node_index])
 
         # Here is where we handle nested list iterations.
         if ast == "list_comp" and self.version != 3.0:
@@ -1434,9 +1443,14 @@ class SourceWalker(GenericASTTraversal, object):
         if node[0].kind == "load_closure":
             self.listcomprehension_walk2(node)
         else:
-            self.comprehension_walk_newer(node, 1, 0)
+            if node == "listcomp_async":
+                list_iter_index = 5
+            else:
+                list_iter_index = 1
+            self.comprehension_walk_newer(node, list_iter_index, 0)
         self.write("]")
         self.prune()
+    n_listcomp_async = n_listcomp
 
     def setcomprehension_walk3(self, node, collection_index):
         """Set comprehensions the way they are done in Python3.