make lib2to3 parse async generators everywhere (GH-6588)

(cherry picked from commit 149addd4960d634ce672ab5fc17e0e785a0cdcd0)

Co-authored-by: Zsolt Dollenstein <zsol.zsol@gmail.com>

1 files changed, 12 insertions, 5 deletions

diff --git a/Lib/lib2to3/tests/test_parser.py b/Lib/lib2to3/tests/test_parser.py
index 1aba0e8..5eefb5a 100644
--- a/Lib/lib2to3/tests/test_parser.py
+++ b/Lib/lib2to3/tests/test_parser.py
@@ -200,20 +200,27 @@ class TestAsyncAwait(GrammarTest):
         self.validate("""await = 1""")
         self.validate("""def async(): pass""")
 
-    def test_async_with(self):
+    def test_async_for(self):
         self.validate("""async def foo():
                              async for a in b: pass""")
 
-        self.invalid_syntax("""def foo():
-                                   async for a in b: pass""")
-
-    def test_async_for(self):
+    def test_async_with(self):
         self.validate("""async def foo():
                              async with a: pass""")
 
         self.invalid_syntax("""def foo():
                                    async with a: pass""")
 
+    def test_async_generator(self):
+        self.validate(
+            """async def foo():
+                   return (i * 2 async for i in arange(42))"""
+        )
+        self.validate(
+            """def foo():
+                   return (i * 2 async for i in arange(42))"""
+        )
+
 
 class TestRaiseChanges(GrammarTest):
     def test_2x_style_1(self):