From e151f83deab9819fb8d9dfc59f9baa4a7273226c Mon Sep 17 00:00:00 2001
From: Yury Selivanov <yury@magic.io>
Date: Tue, 29 May 2018 00:55:27 -0400
Subject: [PATCH] bpo-33672: Fix Task.__repr__ crash with Cython's bogus
 coroutines (GH-7180)

[3.6 backport of 989b9e0]
---
 Lib/asyncio/coroutines.py                     | 23 ++++++++++++-------
 Lib/asyncio/events.py                         |  8 +++----
 Lib/test/test_asyncio/test_events.py          | 22 ++++++++++++++++++
 .../2018-05-28-17-45-06.bpo-33672.GM_Xm_.rst  |  1 +
 4 files changed, 42 insertions(+), 12 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2018-05-28-17-45-06.bpo-33672.GM_Xm_.rst

diff --git a/Lib/asyncio/coroutines.py b/Lib/asyncio/coroutines.py
index 520a309f846..a9022f92a52 100644
--- a/Lib/asyncio/coroutines.py
+++ b/Lib/asyncio/coroutines.py
@@ -310,18 +310,25 @@ def _format_coroutine(coro):
     if coro_name is None:
         coro_name = events._format_callback(func, (), {})
 
-    try:
-        coro_code = coro.gi_code
-    except AttributeError:
+    coro_code = None
+    if hasattr(coro, 'cr_code') and coro.cr_code:
         coro_code = coro.cr_code
+    elif hasattr(coro, 'gi_code') and coro.gi_code:
+        coro_code = coro.gi_code
 
-    try:
-        coro_frame = coro.gi_frame
-    except AttributeError:
+    coro_frame = None
+    if hasattr(coro, 'cr_frame') and coro.cr_frame:
         coro_frame = coro.cr_frame
+    elif hasattr(coro, 'gi_frame') and coro.gi_frame:
+        coro_frame = coro.gi_frame
+
+    filename = '<empty co_filename>'
+    if coro_code and coro_code.co_filename:
+        filename = coro_code.co_filename
 
-    filename = coro_code.co_filename
     lineno = 0
+    coro_repr = coro_name
+
     if (isinstance(coro, CoroWrapper) and
             not inspect.isgeneratorfunction(coro.func) and
             coro.func is not None):
@@ -338,7 +345,7 @@ def _format_coroutine(coro):
         lineno = coro_frame.f_lineno
         coro_repr = ('%s running at %s:%s'
                      % (coro_name, filename, lineno))
-    else:
+    elif coro_code:
         lineno = coro_code.co_firstlineno
         coro_repr = ('%s done, defined at %s:%s'
                      % (coro_name, filename, lineno))
diff --git a/Lib/asyncio/events.py b/Lib/asyncio/events.py
index 05dc8969f44..e654efc5526 100644
--- a/Lib/asyncio/events.py
+++ b/Lib/asyncio/events.py
@@ -58,10 +58,10 @@ def _format_callback(func, args, kwargs, suffix=''):
         suffix = _format_args_and_kwargs(args, kwargs) + suffix
         return _format_callback(func.func, func.args, func.keywords, suffix)
 
-    if hasattr(func, '__qualname__'):
-        func_repr = getattr(func, '__qualname__')
-    elif hasattr(func, '__name__'):
-        func_repr = getattr(func, '__name__')
+    if hasattr(func, '__qualname__') and func.__qualname__:
+        func_repr = func.__qualname__
+    elif hasattr(func, '__name__') and func.__name__:
+        func_repr = func.__name__
     else:
         func_repr = repr(func)
 
diff --git a/Lib/test/test_asyncio/test_events.py b/Lib/test/test_asyncio/test_events.py
index 1ecc89f2e75..548a4610f77 100644
--- a/Lib/test/test_asyncio/test_events.py
+++ b/Lib/test/test_asyncio/test_events.py
@@ -2467,6 +2467,28 @@ class HandleTests(test_utils.TestCase):
         # built-in async_gen.asend().
         self.assertEqual(coroutines._format_coroutine(coro), 'Coro()')
 
+        coro = Coro()
+        coro.__qualname__ = 'AAA'
+        coro.cr_code = None
+        self.assertEqual(coroutines._format_coroutine(coro), 'AAA()')
+
+        coro = Coro()
+        coro.__qualname__ = 'AAA'
+        coro.cr_code = None
+        coro.cr_frame = None
+        self.assertEqual(coroutines._format_coroutine(coro), 'AAA()')
+
+        coro = Coro()
+        coro.__qualname__ = None
+        coro.cr_code = None
+        coro.cr_frame = None
+        self.assertEqual(coroutines._format_coroutine(coro), f'{repr(coro)}()')
+
+        coro = Coro()
+        coro.cr_code = None
+        coro.cr_frame = None
+        self.assertEqual(coroutines._format_coroutine(coro), f'{repr(coro)}()')
+
 
 class TimerTests(unittest.TestCase):
 
diff --git a/Misc/NEWS.d/next/Library/2018-05-28-17-45-06.bpo-33672.GM_Xm_.rst b/Misc/NEWS.d/next/Library/2018-05-28-17-45-06.bpo-33672.GM_Xm_.rst
new file mode 100644
index 00000000000..36373c02863
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-05-28-17-45-06.bpo-33672.GM_Xm_.rst
@@ -0,0 +1 @@
+Fix Task.__repr__ crash with Cython's bogus coroutines