pytest-rerunfailures插件之测试用例失败重跑

环境前提：

只有同时满足一下先决条件才能使用pytest-rerunfailures

①python的版本不能过低；

②pytest 5.0或更高版本；

背景：

平时在做接口测试的时候，经常会遇到网络抖动或者环境问题导致测试用例运行失败，而这个并不是我们想要的结果；

我们想要重新运行失败的测试用例，这个就需要通过插件pytest-rerunfailures来实现了。

安装插件pytest-rerunfailures

<span style="color:#111111"><span style="background-color:#ffffff"><code class="language-mipsasm">pip <span style="color:#0000ff">install </span>pytest-rerunfailures
</code></span></span>

①执行命令重新执行失败的测试用例：使用 --reruns 命令行参数选项，并指定要运行测试的最大次数：

<span style="color:#111111"><span style="background-color:#ffffff"><code class="language-bash">pytest test_add.py --reruns NUM    <span style="color:#008000"># NUM表示重试的次数</span>
</code></span></span>

【注意】重复运行失败的测试用例时，对应的fixture或者setup函数也会重新执行（例如：scope参数为method的fixture前置函数）

举例：

代码参考如下：

<span style="color:#111111"><span style="background-color:#ffffff"><code class="language-python"><span style="color:#008000"># file_name: test_add.py</span>


<span style="color:#0000ff">import</span> pytest


<span style="color:#0000ff">def</span> <span style="color:#a31515">test_add01</span>():
    <span style="color:#0000ff">print</span>(<span style="color:#a31515">"----------------->>> test_add01"</span>)
    <span style="color:#0000ff">assert</span> <span style="color:#880000">1</span>


<span style="color:#0000ff">def</span> <span style="color:#a31515">test_add02</span>():
    <span style="color:#0000ff">print</span>(<span style="color:#a31515">"----------------->>> test_add02"</span>)
    <span style="color:#0000ff">assert</span> <span style="color:#880000">0</span>


<span style="color:#0000ff">def</span> <span style="color:#a31515">test_add03</span>():
    <span style="color:#0000ff">print</span>(<span style="color:#a31515">"----------------->>> test_add03"</span>)
    <span style="color:#0000ff">assert</span> <span style="color:#880000">1</span>


<span style="color:#0000ff">def</span> <span style="color:#a31515">test_add04</span>():
    <span style="color:#0000ff">print</span>(<span style="color:#a31515">"----------------->>> test_add04"</span>)
    <span style="color:#0000ff">assert</span> <span style="color:#880000">1</span>


<span style="color:#0000ff">if</span> __name__ == <span style="color:#a31515">'__main__'</span>:
    pytest.main([<span style="color:#a31515">"-s"</span>, <span style="color:#a31515">"test_add.py"</span>])
</code></span></span>

执行命令：pytest ./pytest_study/test_add.py --reruns 2 -s（NUM=2表示失败测试用例重试2次，上述代码中只有test_add02()方法会失败）

注意：

pytest多种运行模式支持叠加执行：

例如同时运行四个进程，且失败后重跑2次，pytest命令行运行：pytest -n 4 -reruns 2

②设置添加重新执行的延时时间并执行失败的测试用例

要在两次重试之间增加延迟时间，使用 --reruns-delay 命令行选项，指定下次测试重新开始之前等待的秒数：

<span style="color:#111111"><span style="background-color:#ffffff"><code class="language-css">pytest <span style="color:#ff0000">--reruns</span> <span style="color:#880000">5</span> <span style="color:#ff0000">--reruns-delay</span> <span style="color:#880000">10</span>
</code></span></span>

③重新运行指定的测试用例：测试用例失败重跑的装饰器用法

添加flaky装饰器 @pytest.mark.flaky(reruns=5) ，并指定最大重新运行次数。

示例代码如下：

<span style="color:#111111"><span style="background-color:#ffffff"><code class="language-python"><span style="color:#008000">#-*- coding: utf-8 -*-</span>
<span style="color:#0000ff">import</span> random
<span style="color:#0000ff">import</span> pytest


<span style="color:#2b91af">@pytest.mark.flaky(reruns=<span style="color:#880000">5</span>)</span>
<span style="color:#0000ff">def</span> <span style="color:#a31515">test_retry1</span>():
    n = random.randint(<span style="color:#880000">0</span>, <span style="color:#880000">9</span>)
    <span style="color:#0000ff">print</span>(<span style="color:#a31515">f"\n 输出随机数： {n} "</span>)
    <span style="color:#0000ff">assert</span> n == <span style="color:#880000">2</span>


<span style="color:#2b91af">@pytest.mark.flaky(reruns=<span style="color:#880000">5</span>)</span>
<span style="color:#0000ff">def</span> <span style="color:#a31515">test_retry2</span>():
    <span style="color:#0000ff">assert</span> random.choice([<span style="color:#a31515">True</span>, <span style="color:#a31515">False</span>, <span style="color:#a31515">False</span>])
</code></span></span>

运行结果：【注意】测试结果以最后一次重新执行测试用例的结果为最终结果，即用例执行被判定为FAILED或者PASSED

第一个测试方法：

第二个测试方法：

④对单个测试用例设置重新运行等待延迟时间

实例代码：

<span style="color:#111111"><span style="background-color:#ffffff"><code class="language-python"><span style="color:#2b91af">@pytest.mark.flaky(reruns=<span style="color:#880000">5</span>,reruns_delay=<span style="color:#880000">2</span>)</span>
<span style="color:#0000ff">def</span> <span style="color:#a31515">test_retry1</span>():
    n = random.randint(<span style="color:#880000">0</span>, <span style="color:#880000">9</span>)
    <span style="color:#0000ff">print</span>(<span style="color:#a31515">f"\n 输出随机数： {n} "</span>)
    <span style="color:#0000ff">assert</span> n == <span style="color:#880000">2</span>
</code></span></span>

运行结果：