我有一个Django测试，我需要模拟datetime.now（），因为它测试的视图使用datetime.now（）
我正在使用Michael Foord的模拟库1.0.1版 我正在寻找一种解决方案而不使用其他库，例如freezegun。
大多数示例如this和this都会导入日期时间并覆盖它，但我正在导入datetime.datetime并尝试覆盖它，并且由于某种原因这不起作用。
覆盖日期时间：
<meta http-equiv="Cache-control" content="public, max-age=3600">
<meta http-equiv="Expires" content="public, max-age=3600">
<meta http-equiv="Last-Modified" content="public, max-age=3600">
但我想导入datetime.datetime并执行以下操作：
Creating myapp-debug-unaligned.apk and signing it with a debug key...
C:\Users\m0unta\AppData\Local\Android\android-sdk\tools\ant\build.xml:960: The following error occurred while executing this line:
C:\Users\m0unta\AppData\Local\Android\android-sdk\tools\ant\build.xml:971: The following error occurred while executing this line:
C:\Users\m0unta\AppData\Local\Android\android-sdk\tools\ant\build.xml:314:
java.lang.NoClassDefFoundError: Could not initialize class sun.security.x509.X500Name
at com.android.sdklib.internal.build.SignedJarBuilder.writeSignatureBlock(SignedJarBuilder.java:384)
at com.android.sdklib.internal.build.SignedJarBuilder.close(SignedJarBuilder.java:273)
at com.android.sdklib.build.ApkBuilder.sealApk(ApkBuilder.java:795)
at com.android.ant.ApkBuilderTask.execute(ApkBuilderTask.java:371)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.MacroInstance.execute(MacroInstance.java:396)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
at com.android.ant.IfElseTask.execute(IfElseTask.java:124)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
at com.android.ant.IfElseTask.execute(IfElseTask.java:124)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.MacroInstance.execute(MacroInstance.java:396)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor269.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.Target.execute(Target.java:435)
at org.apache.tools.ant.Target.performTasks(Target.java:456)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1405)
at org.apache.tools.ant.Project.executeTarget(Project.java:1376)
at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
at org.apache.tools.ant.Project.executeTargets(Project.java:1260)
at org.apache.tools.ant.module.bridge.impl.BridgeImpl.run(BridgeImpl.java:286)
at org.apache.tools.ant.module.run.TargetExecutor.run(TargetExecutor.java:555)
at org.netbeans.core.execution.RunClassThread.run(RunClassThread.java:153)
BUILD FAILED (total time: 2 seconds)
这会导致TypeError：需要一个有效的目标来修补。您提供了：'datetime'。
Mock库还声明：
target应该是'package.module.ClassName'形式的字符串。导入目标并将指定的对象替换为新对象，因此目标必须可从您调用补丁的环境中导入。
有没有办法只追踪日期时间而不是datetime.datetime？
的Nb。我也看到this示例，但它对我不起作用，因为我没有一个返回日期时间的函数，但我的视图使用datetime.now（）
答案 0 :(得分：1)
您正在测试的模块中应该有patch个对象，而不是带有测试的模块中的对象。
基于代码的最小工作示例：
<强> app.py
from datetime import datetime
def my_great_func():
# do something
return datetime.now()
tests.py （请注意修补<{strong> datetime中的app.py 的方式）
from datetime import datetime
from unittest import mock
from app import my_great_func
@mock.patch('app.datetime')
def test_my_great_func(mocked_datetime):
mocked_datetime.now.return_value = datetime(2010, 1, 1)
assert my_great_func() == datetime(2010, 1, 1)
测试执行结果：
$ pytest -vvv tests.py
======================= test session starts =========================
platform linux -- Python 3.5.2, pytest-3.2.1, py-1.4.34, pluggy-0.4.0
cachedir: .cache
rootdir: /home/kris/projects/tmp, inifile:
plugins: mock-1.6.2, celery-4.1.0
collected 1 item
tests.py::test_my_great_func PASSED
==================== 1 passed in 0.00 seconds =======================