Issue 24226: Fix parsing of many sequential one-line 'def' statements.

Lib/test/test_coroutines.py

@@ -1,4 +1,5 @@
 import contextlib
+import inspect
 import sys
 import types
 import unittest
@@ -87,6 +88,28 @@ class AsyncBadSyntaxTest(unittest.TestCase):
             import test.badsyntax_async9
 
 
+class TokenizerRegrTest(unittest.TestCase):
+
+    def test_oneline_defs(self):
+        buf = []
+        for i in range(500):
+            buf.append('def i{i}(): return {i}'.format(i=i))
+        buf = '\n'.join(buf)
+
+        # Test that 500 consequent, one-line defs is OK
+        ns = {}
+        exec(buf, ns, ns)
+        self.assertEqual(ns['i499'](), 499)
+
+        # Test that 500 consequent, one-line defs *and*
+        # one 'async def' following them is OK
+        buf += '\nasync def foo():\n    return'
+        ns = {}
+        exec(buf, ns, ns)
+        self.assertEqual(ns['i499'](), 499)
+        self.assertTrue(inspect.iscoroutinefunction(ns['foo']))
+
+
 class CoroutineTest(unittest.TestCase):
 
     def test_gen_1(self):