get rid of exc_info-using code

Author: radix

txeffect/__init__.py

@@ -13,10 +13,7 @@
 does.
 """
 
-from __future__ import absolute_import
-
 from functools import partial
-import sys
 
 from twisted.internet.defer import Deferred
 from twisted.python.failure import Failure
@@ -27,15 +24,15 @@
     ParallelEffects,
     perform as base_perform,
     TypeDispatcher)
-from effect.async import perform_parallel_async
+from effect.parallel_async import perform_parallel_async
 from effect._utils import wraps  # whoah there
 
 
 def deferred_to_box(d, box):
     """
     Make a Deferred pass its success or fail events on to the given box.
     """
-    d.addCallbacks(box.succeed, lambda f: box.fail((f.type, f.value, f.tb)))
+    d.addCallbacks(box.succeed, lambda f: box.fail(f.value))
 
 
 def make_twisted_dispatcher(reactor):
@@ -71,8 +68,8 @@ def deferred_wrapper(*args, **kwargs):
         pass_args = args[:-1]
         try:
             result = f(*pass_args, **kwargs)
-        except:
-            box.fail(sys.exc_info())
+        except Exception as e:
+            box.fail(e)
         else:
             if isinstance(result, Deferred):
                 deferred_to_box(result, box)
@@ -97,11 +94,6 @@ def perform(dispatcher, effect):
     d = Deferred()
     eff = effect.on(
         success=d.callback,
-        error=lambda e: d.errback(exc_info_to_failure(e)))
+        error=lambda e: d.errback(e))
     base_perform(dispatcher, eff)
     return d
-
-
-def exc_info_to_failure(exc_info):
-    """Convert an exc_info tuple to a :class:`Failure`."""
-    return Failure(exc_info[1], exc_info[0], exc_info[2])

txeffect/test_txeffect.py

@@ -4,7 +4,7 @@
 import sys
 
 from testtools import TestCase
-from testtools.matchers import MatchesListwise, Equals, MatchesException
+from testtools.matchers import MatchesListwise, Equals
 
 from twisted.trial.unittest import SynchronousTestCase
 from twisted.internet.defer import Deferred
@@ -16,9 +16,9 @@
     base_dispatcher, parallel,
     ComposedDispatcher,
 )
+from effect._test_utils import MatchesException
 from . import (
     deferred_performer,
-    exc_info_to_failure,
     make_twisted_dispatcher,
     perform)
 
@@ -95,14 +95,22 @@ def test_perform_failure(self):
         effect.twisted.perform fails the Deferred it returns if the ultimate
         result of the Effect is an exception.
         """
+        try:
+            raise ValueError("oh dear")
+        except Exception as e:
+            exc = e
+
         boxes = []
         e = Effect(boxes.append)
         d = perform(func_dispatcher, e)
         self.assertNoResult(d)
-        boxes[0].fail((ValueError, ValueError("oh dear"), None))
+        boxes[0].fail(exc)
         f = self.failureResultOf(d)
         self.assertEqual(f.type, ValueError)
         self.assertEqual(str(f.value), 'oh dear')
+        self.assertRegex(
+            f.getTraceback().splitlines()[-3],
+            '^\s+File ".*?test_txeffect.py", line \d+, in test_perform_failure$')
 
 
 class DeferredPerformerTests(TestCase):
@@ -219,22 +227,3 @@ def p(dispatcher, intent, extra):
         dispatcher = lambda _: partial(p, extra='extra val')
         result = self.successResultOf(perform(dispatcher, Effect('foo')))
         self.assertEqual(result, 'extra val')
-
-
-class ExcInfoToFailureTests(TestCase):
-    """Tests for :func:`exc_info_to_failure`."""
-
-    def test_exc_info_to_failure(self):
-        """
-        :func:`exc_info_to_failure` converts an exc_info tuple to a
-        :obj:`Failure`.
-        """
-        try:
-            raise RuntimeError("foo")
-        except:
-            exc_info = sys.exc_info()
-
-        failure = exc_info_to_failure(exc_info)
-        self.assertIs(failure.type, RuntimeError)
-        self.assertEqual(str(failure.value), "foo")
-        self.assertIs(failure.tb, exc_info[2])