def test_errbackResultChangesValue(self):
"""
The result of an errback affects the result returned from
C{synchronize}.
"""
sd = SynchronousDeferred(SynchronousFailure(RuntimeError()))
sd.addErrback(lambda r: 42)
self.assertEquals(sd.synchronize(), 42)
def test_errbackResultChangesNextCallbackArgument(self):
"""
The result of an errback affects the argument passed to the next
callback.
"""
sd = SynchronousDeferred(SynchronousFailure(RuntimeError()))
sd.addErrback(lambda r: 42)
l = []
sd.addCallback(l.append)
self.assertEquals(l, [42])
def test_errorRaisingErrback(self):
"""
If an errback raises an exception, errbacks will be called.
"""
sd = SynchronousDeferred(SynchronousFailure(RuntimeError()))
def errback(ignored):
1/0
sd.addErrback(errback)
l = []
sd.addErrback(l.append)
self.assertEquals(len(l), 1)
self.assertTrue(l[0].check(ZeroDivisionError))
def test_errorRaisingCallback(self):
"""
If a callback raises an exception, errbacks will be called.
"""
sd = SynchronousDeferred("foo")
def callback(ignored):
1/0
sd.addCallback(callback)
l = []
sd.addErrback(l.append)
self.assertEquals(len(l), 1)
self.assertTrue(l[0].check(ZeroDivisionError))
def test_addErrback(self):
"""
C{addErrback} immediately calls the errback when the current result is
a failure.
"""
failure = SynchronousFailure(RuntimeError())
sd = SynchronousDeferred(failure)
l = []
self.assertEquals(sd.addErrback(l.append), sd)
self.assertEquals(l, [failure])
