From 11e0cff40cb070d196ab61fb86e2fce22facbf46 Mon Sep 17 00:00:00 2001
From: Jean-Paul Calderone <exarkun@twistedmatrix.com>
Date: Tue, 3 Dec 2019 10:00:15 -0500
Subject: [PATCH] Factor safe Clock creation into a strategy for reuse
---
src/_zkapauthorizer/tests/strategies.py | 39 ++++++++++++++++++++
src/_zkapauthorizer/tests/test_controller.py | 30 ++++-----------
2 files changed, 46 insertions(+), 23 deletions(-)
diff --git a/src/_zkapauthorizer/tests/strategies.py b/src/_zkapauthorizer/tests/strategies.py
index 223a7ec..4402065 100644
--- a/src/_zkapauthorizer/tests/strategies.py
+++ b/src/_zkapauthorizer/tests/strategies.py
@@ -19,6 +19,9 @@ Hypothesis strategies for property testing.
from base64 import (
urlsafe_b64encode,
)
+from datetime import (
+ datetime,
+)
import attr
@@ -39,6 +42,9 @@ from hypothesis.strategies import (
datetimes,
)
+from twisted.internet.task import (
+ Clock,
+)
from twisted.web.test.requesthelper import (
DummyRequest,
)
@@ -541,3 +547,36 @@ def announcements():
return just({
u"ristretto-issuer-root-url": u"https://issuer.example.invalid/",
})
+
+
+_POSIX_EPOCH = datetime.utcfromtimestamp(0)
+
+def posix_safe_datetimes():
+ """
+ Build datetime instances in a range that can be represented as floats
+ without losing microsecond precision.
+ """
+ return datetimes(
+ # I don't know that time-based parts of the system break down
+ # before the POSIX epoch but I don't know that they work, either.
+ # Don't time travel with this code.
+ min_value=_POSIX_EPOCH,
+ # Once we get far enough into the future we lose the ability to
+ # represent a timestamp with microsecond precision in a floating point
+ # number, which we do with any POSIX timestamp-like API (eg
+ # twisted.internet.task.Clock). So don't go far enough into the
+ # future.
+ max_value=datetime(2200, 1, 1),
+ )
+
+
+def clocks(now=posix_safe_datetimes()):
+ """
+ Build ``twisted.internet.task.Clock`` instances set to a time built by
+ ``now``.
+ """
+ def clock_at_time(when):
+ c = Clock()
+ c.advance((when - _POSIX_EPOCH).total_seconds())
+ return c
+ return now.map(clock_at_time)
diff --git a/src/_zkapauthorizer/tests/test_controller.py b/src/_zkapauthorizer/tests/test_controller.py
index 672c95f..5485b16 100644
--- a/src/_zkapauthorizer/tests/test_controller.py
+++ b/src/_zkapauthorizer/tests/test_controller.py
@@ -64,9 +64,6 @@ from hypothesis.strategies import (
from twisted.python.url import (
URL,
)
-from twisted.internet.task import (
- Clock,
-)
from twisted.internet.defer import (
fail,
)
@@ -119,6 +116,7 @@ from .strategies import (
tahoe_configs,
vouchers,
voucher_objects,
+ clocks,
)
from .matchers import (
Provides,
@@ -127,8 +125,6 @@ from .fixtures import (
TemporaryVoucherStore,
)
-POSIX_EPOCH = datetime.utcfromtimestamp(0)
-
class PaymentControllerTests(TestCase):
"""
Tests for ``PaymentController``.
@@ -232,32 +228,20 @@ class PaymentControllerTests(TestCase):
@given(
tahoe_configs(),
- datetimes(
- # I don't know that time-based parts of the system break down
- # before the POSIX epoch but I don't know that they work, either.
- # Don't time travel with this code.
- min_value=POSIX_EPOCH,
- # Once we get far enough into the future we lose the ability to
- # represent a timestamp with microsecond precision in a floating
- # point number, which we do with Clock. So don't go far enough
- # into the future.
- max_value=datetime(2200, 1, 1),
- ),
+ clocks(),
vouchers(),
)
- def test_redeem_error_after_delay(self, get_config, now, voucher):
+ def test_redeem_error_after_delay(self, get_config, clock, voucher):
"""
When ``PaymentController`` receives a non-terminal error trying to redeem
a voucher, after some time passes it tries to redeem the voucher
again.
"""
- clock = Clock()
- clock.advance((now - POSIX_EPOCH).total_seconds())
-
+ datetime_now = lambda: datetime.utcfromtimestamp(clock.seconds())
store = self.useFixture(
TemporaryVoucherStore(
get_config,
- lambda: datetime.utcfromtimestamp(clock.seconds()),
+ datetime_now,
),
).store
controller = PaymentController(
@@ -272,7 +256,7 @@ class PaymentControllerTests(TestCase):
MatchesAll(
IsInstance(model_Unpaid),
MatchesStructure(
- finished=Equals(now),
+ finished=Equals(datetime_now()),
),
)
)
@@ -288,7 +272,7 @@ class PaymentControllerTests(TestCase):
IsInstance(model_Unpaid),
MatchesStructure(
# At the new time, demonstrating the retry was performed.
- finished=Equals(now + interval),
+ finished=Equals(datetime_now()),
),
),
)
--
GitLab