From 8ecf00bd0e91bf5705446a5953eef20f4477bcdc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Mon, 23 Sep 2019 03:58:33 +0200
Subject: [PATCH] tests: add helpful decorator to wait before test cleanup

Allow to manual inspect test environment after test fails. This is
similar to --do-not-clean option we had in R3.2.

The decorator should be used only while debugging and should never be
applied to the code committed into repository.
---
 qubes/tests/__init__.py | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/qubes/tests/__init__.py b/qubes/tests/__init__.py
index d45943a7..334f85e2 100644
--- a/qubes/tests/__init__.py
+++ b/qubes/tests/__init__.py
@@ -220,6 +220,34 @@ def expectedFailureIfTemplate(templates):
         return wrapper
     return decorator
 
+
+def wait_on_fail(func):
+    """Test decorator for debugging. It pause test execution on failure and wait
+    for user input. It's useful to manually inspect system state just after test
+    fails, before executing any cleanup.
+
+    Usage: decorate a test you are debugging.
+    DO IT ONLY TEMPORARILY, DO NOT COMMIT!
+    """
+
+    @functools.wraps(func)
+    def wrapper(self, *args, **kwargs):
+        try:
+            func(self, *args, **kwargs)
+        except:
+            print('FAIL\n')
+            traceback.print_exc()
+            print('Press return to continue:', end='')
+            sys.stdout.flush()
+            reader = asyncio.StreamReader(loop=self.loop)
+            transport, protocol = self.loop.run_until_complete(
+                self.loop.connect_read_pipe(lambda: asyncio.StreamReaderProtocol(reader),
+                                            sys.stdin))
+            self.loop.run_until_complete(reader.readline())
+            raise
+    return wrapper
+
+
 class _AssertNotRaisesContext(object):
     """A context manager used to implement TestCase.assertNotRaises methods.