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  <div class="section" id="module-unittest">
<span id="unittest-unit-testing-framework"></span><h1>25.3. <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> — Unit testing framework<a class="headerlink" href="#module-unittest" title="Permalink to this headline">¶</a></h1>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.1.</span></p>
</div>
<p>(If you are already familiar with the basic concepts of testing, you might want
to skip to <a class="reference internal" href="#assert-methods"><span class="std std-ref">the list of assert methods</span></a>.)</p>
<p>The Python unit testing framework, sometimes referred to as “PyUnit,” is a
Python language version of JUnit, by Kent Beck and Erich Gamma. JUnit is, in
turn, a Java version of Kent’s Smalltalk testing framework.  Each is the de
facto standard unit testing framework for its respective language.</p>
<p><a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> supports test automation, sharing of setup and shutdown code for
tests, aggregation of tests into collections, and independence of the tests from
the reporting framework.  The <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> module provides classes that make
it easy to support these qualities for a set of tests.</p>
<p>To achieve this, <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> supports some important concepts:</p>
<dl class="simple">
<dt>test fixture</dt><dd><p>A <em class="dfn">test fixture</em> represents the preparation needed to perform one or more
tests, and any associate cleanup actions.  This may involve, for example,
creating temporary or proxy databases, directories, or starting a server
process.</p>
</dd>
<dt>test case</dt><dd><p>A <em class="dfn">test case</em> is the smallest unit of testing.  It checks for a specific
response to a particular set of inputs.  <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> provides a base class,
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>, which may be used to create new test cases.</p>
</dd>
<dt>test suite</dt><dd><p>A <em class="dfn">test suite</em> is a collection of test cases, test suites, or both.  It is
used to aggregate tests that should be executed together.</p>
</dd>
<dt>test runner</dt><dd><p>A <em class="dfn">test runner</em> is a component which orchestrates the execution of tests
and provides the outcome to the user.  The runner may use a graphical interface,
a textual interface, or return a special value to indicate the results of
executing the tests.</p>
</dd>
</dl>
<p>The test case and test fixture concepts are supported through the
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> and <a class="reference internal" href="#unittest.FunctionTestCase" title="unittest.FunctionTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">FunctionTestCase</span></code></a> classes; the former should be
used when creating new tests, and the latter can be used when integrating
existing test code with a <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>-driven framework. When building test
fixtures using <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>, the <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> and
<a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> methods can be overridden to provide initialization
and cleanup for the fixture.  With <a class="reference internal" href="#unittest.FunctionTestCase" title="unittest.FunctionTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">FunctionTestCase</span></code></a>, existing functions
can be passed to the constructor for these purposes.  When the test is run, the
fixture initialization is run first; if it succeeds, the cleanup method is run
after the test has been executed, regardless of the outcome of the test.  Each
instance of the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> will only be used to run a single test method,
so a new fixture is created for each test.</p>
<p>Test suites are implemented by the <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> class.  This class allows
individual tests and test suites to be aggregated; when the suite is executed,
all tests added directly to the suite and in “child” test suites are run.</p>
<p>A test runner is an object that provides a single method,
<code class="xref py py-meth docutils literal notranslate"><span class="pre">run()</span></code>, which accepts a <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> or <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a>
object as a parameter, and returns a result object.  The class
<a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> is provided for use as the result object. <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>
provides the <a class="reference internal" href="#unittest.TextTestRunner" title="unittest.TextTestRunner"><code class="xref py py-class docutils literal notranslate"><span class="pre">TextTestRunner</span></code></a> as an example test runner which reports
test results on the standard error stream by default.  Alternate runners can be
implemented for other environments (such as graphical environments) without any
need to derive from a specific class.</p>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<dl class="simple">
<dt>Module <a class="reference internal" href="doctest.html#module-doctest" title="doctest: Test pieces of code within docstrings."><code class="xref py py-mod docutils literal notranslate"><span class="pre">doctest</span></code></a></dt><dd><p>Another test-support module with a very different flavor.</p>
</dd>
<dt><a class="reference external" href="https://pypi.org/project/unittest2">unittest2: A backport of new unittest features for Python 2.4-2.6</a></dt><dd><p>Many new features were added to unittest in Python 2.7, including test
discovery. unittest2 allows you to use these features with earlier
versions of Python.</p>
</dd>
<dt><a class="reference external" href="https://web.archive.org/web/20150315073817/http://www.xprogramming.com/testfram.htm">Simple Smalltalk Testing: With Patterns</a></dt><dd><p>Kent Beck’s original paper on testing frameworks using the pattern shared
by <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>.</p>
</dd>
<dt><a class="reference external" href="https://nose.readthedocs.io/">Nose</a> and <a class="reference external" href="https://docs.pytest.org/">pytest</a></dt><dd><p>Third-party unittest frameworks with a lighter-weight syntax for writing
tests.  For example, <code class="docutils literal notranslate"><span class="pre">assert</span> <span class="pre">func(10)</span> <span class="pre">==</span> <span class="pre">42</span></code>.</p>
</dd>
<dt><a class="reference external" href="https://wiki.python.org/moin/PythonTestingToolsTaxonomy">The Python Testing Tools Taxonomy</a></dt><dd><p>An extensive list of Python testing tools including functional testing
frameworks and mock object libraries.</p>
</dd>
<dt><a class="reference external" href="http://lists.idyll.org/listinfo/testing-in-python">Testing in Python Mailing List</a></dt><dd><p>A special-interest-group for discussion of testing, and testing tools,
in Python.</p>
</dd>
</dl>
</div>
<div class="section" id="basic-example">
<span id="unittest-minimal-example"></span><h2>25.3.1. Basic example<a class="headerlink" href="#basic-example" title="Permalink to this headline">¶</a></h2>
<p>The <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> module provides a rich set of tools for constructing and
running tests.  This section demonstrates that a small subset of the tools
suffice to meet the needs of most users.</p>
<p>Here is a short script to test three string methods:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">unittest</span>

<span class="k">class</span> <span class="nc">TestStringMethods</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>

    <span class="k">def</span> <span class="nf">test_upper</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="s1">&#39;foo&#39;</span><span class="o">.</span><span class="n">upper</span><span class="p">(),</span> <span class="s1">&#39;FOO&#39;</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">test_isupper</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertTrue</span><span class="p">(</span><span class="s1">&#39;FOO&#39;</span><span class="o">.</span><span class="n">isupper</span><span class="p">())</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertFalse</span><span class="p">(</span><span class="s1">&#39;Foo&#39;</span><span class="o">.</span><span class="n">isupper</span><span class="p">())</span>

    <span class="k">def</span> <span class="nf">test_split</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="n">s</span> <span class="o">=</span> <span class="s1">&#39;hello world&#39;</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="n">s</span><span class="o">.</span><span class="n">split</span><span class="p">(),</span> <span class="p">[</span><span class="s1">&#39;hello&#39;</span><span class="p">,</span> <span class="s1">&#39;world&#39;</span><span class="p">])</span>
        <span class="c1"># check that s.split fails when the separator is not a string</span>
        <span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">assertRaises</span><span class="p">(</span><span class="ne">TypeError</span><span class="p">):</span>
            <span class="n">s</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="mi">2</span><span class="p">)</span>

<span class="k">if</span> <span class="vm">__name__</span> <span class="o">==</span> <span class="s1">&#39;__main__&#39;</span><span class="p">:</span>
    <span class="n">unittest</span><span class="o">.</span><span class="n">main</span><span class="p">()</span>
</pre></div>
</div>
<p>A testcase is created by subclassing <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">unittest.TestCase</span></code></a>.  The three
individual tests are defined with methods whose names start with the letters
<code class="docutils literal notranslate"><span class="pre">test</span></code>.  This naming convention informs the test runner about which methods
represent tests.</p>
<p>The crux of each test is a call to <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a> to check for an
expected result; <a class="reference internal" href="#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTrue()</span></code></a> or <a class="reference internal" href="#unittest.TestCase.assertFalse" title="unittest.TestCase.assertFalse"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertFalse()</span></code></a>
to verify a condition; or <a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a> to verify that a
specific exception gets raised.  These methods are used instead of the
<a class="reference internal" href="../reference/simple_stmts.html#assert"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">assert</span></code></a> statement so the test runner can accumulate all test results
and produce a report.</p>
<p>The <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> and <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> methods allow you
to define instructions that will be executed before and after each test method.
They are covered in more detail in the section <a class="reference internal" href="#organizing-tests"><span class="std std-ref">Organizing test code</span></a>.</p>
<p>The final block shows a simple way to run the tests. <a class="reference internal" href="#unittest.main" title="unittest.main"><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.main()</span></code></a>
provides a command-line interface to the test script.  When run from the command
line, the above script produces an output that looks like this:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="o">...</span>
<span class="o">----------------------------------------------------------------------</span>
<span class="n">Ran</span> <span class="mi">3</span> <span class="n">tests</span> <span class="ow">in</span> <span class="mf">0.000</span><span class="n">s</span>

<span class="n">OK</span>
</pre></div>
</div>
<p>Instead of <a class="reference internal" href="#unittest.main" title="unittest.main"><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.main()</span></code></a>, there are other ways to run the tests with a
finer level of control, less terse output, and no requirement to be run from the
command line.  For example, the last two lines may be replaced with:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">suite</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestLoader</span><span class="p">()</span><span class="o">.</span><span class="n">loadTestsFromTestCase</span><span class="p">(</span><span class="n">TestStringMethods</span><span class="p">)</span>
<span class="n">unittest</span><span class="o">.</span><span class="n">TextTestRunner</span><span class="p">(</span><span class="n">verbosity</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span><span class="o">.</span><span class="n">run</span><span class="p">(</span><span class="n">suite</span><span class="p">)</span>
</pre></div>
</div>
<p>Running the revised script from the interpreter or another script produces the
following output:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">test_isupper</span> <span class="p">(</span><span class="n">__main__</span><span class="o">.</span><span class="n">TestStringMethods</span><span class="p">)</span> <span class="o">...</span> <span class="n">ok</span>
<span class="n">test_split</span> <span class="p">(</span><span class="n">__main__</span><span class="o">.</span><span class="n">TestStringMethods</span><span class="p">)</span> <span class="o">...</span> <span class="n">ok</span>
<span class="n">test_upper</span> <span class="p">(</span><span class="n">__main__</span><span class="o">.</span><span class="n">TestStringMethods</span><span class="p">)</span> <span class="o">...</span> <span class="n">ok</span>

<span class="o">----------------------------------------------------------------------</span>
<span class="n">Ran</span> <span class="mi">3</span> <span class="n">tests</span> <span class="ow">in</span> <span class="mf">0.001</span><span class="n">s</span>

<span class="n">OK</span>
</pre></div>
</div>
<p>The above examples show the most commonly used <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> features which
are sufficient to meet many everyday testing needs.  The remainder of the
documentation explores the full feature set from first principles.</p>
</div>
<div class="section" id="command-line-interface">
<span id="unittest-command-line-interface"></span><h2>25.3.2. Command-Line Interface<a class="headerlink" href="#command-line-interface" title="Permalink to this headline">¶</a></h2>
<p>The unittest module can be used from the command line to run tests from
modules, classes or even individual test methods:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="n">test_module1</span> <span class="n">test_module2</span>
<span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="n">test_module</span><span class="o">.</span><span class="n">TestClass</span>
<span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="n">test_module</span><span class="o">.</span><span class="n">TestClass</span><span class="o">.</span><span class="n">test_method</span>
</pre></div>
</div>
<p>You can pass in a list with any combination of module names, and fully
qualified class or method names.</p>
<p>You can run tests with more detail (higher verbosity) by passing in the -v flag:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="o">-</span><span class="n">v</span> <span class="n">test_module</span>
</pre></div>
</div>
<p>For a list of all the command-line options:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="o">-</span><span class="n">h</span>
</pre></div>
</div>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span>In earlier versions it was only possible to run individual test methods and
not modules or classes.</p>
</div>
<div class="section" id="command-line-options">
<h3>25.3.2.1. Command-line options<a class="headerlink" href="#command-line-options" title="Permalink to this headline">¶</a></h3>
<p><strong class="program">unittest</strong> supports these command-line options:</p>
<dl class="cmdoption">
<dt id="cmdoption-unittest-b">
<code class="descname">-b</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--buffer</code><code class="descclassname"></code><a class="headerlink" href="#cmdoption-unittest-b" title="Permalink to this definition">¶</a></dt>
<dd><p>The standard output and standard error streams are buffered during the test
run. Output during a passing test is discarded. Output is echoed normally
on test fail or error and is added to the failure messages.</p>
</dd></dl>

<dl class="cmdoption">
<dt id="cmdoption-unittest-c">
<code class="descname">-c</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--catch</code><code class="descclassname"></code><a class="headerlink" href="#cmdoption-unittest-c" title="Permalink to this definition">¶</a></dt>
<dd><p><kbd class="kbd docutils literal notranslate">Control-C</kbd> during the test run waits for the current test to end and then
reports all the results so far. A second <kbd class="kbd docutils literal notranslate">Control-C</kbd> raises the normal
<a class="reference internal" href="exceptions.html#exceptions.KeyboardInterrupt" title="exceptions.KeyboardInterrupt"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyboardInterrupt</span></code></a> exception.</p>
<p>See <a class="reference internal" href="#signal-handling">Signal Handling</a> for the functions that provide this functionality.</p>
</dd></dl>

<dl class="cmdoption">
<dt id="cmdoption-unittest-f">
<code class="descname">-f</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--failfast</code><code class="descclassname"></code><a class="headerlink" href="#cmdoption-unittest-f" title="Permalink to this definition">¶</a></dt>
<dd><p>Stop the test run on the first error or failure.</p>
</dd></dl>

<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7: </span>The command-line options <code class="docutils literal notranslate"><span class="pre">-b</span></code>, <code class="docutils literal notranslate"><span class="pre">-c</span></code> and <code class="docutils literal notranslate"><span class="pre">-f</span></code> were added.</p>
</div>
<p>The command line can also be used for test discovery, for running all of the
tests in a project or just a subset.</p>
</div>
</div>
<div class="section" id="test-discovery">
<span id="unittest-test-discovery"></span><h2>25.3.3. Test Discovery<a class="headerlink" href="#test-discovery" title="Permalink to this headline">¶</a></h2>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
<p>Unittest supports simple test discovery. In order to be compatible with test
discovery, all of the test files must be <a class="reference internal" href="../tutorial/modules.html#tut-modules"><span class="std std-ref">modules</span></a> or
<a class="reference internal" href="../tutorial/modules.html#tut-packages"><span class="std std-ref">packages</span></a> importable from the top-level directory of
the project (this means that their filenames must be valid
<a class="reference internal" href="../reference/lexical_analysis.html#identifiers"><span class="std std-ref">identifiers</span></a>).</p>
<p>Test discovery is implemented in <a class="reference internal" href="#unittest.TestLoader.discover" title="unittest.TestLoader.discover"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestLoader.discover()</span></code></a>, but can also be
used from the command line. The basic command-line usage is:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">cd</span> <span class="n">project_directory</span>
<span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="n">discover</span>
</pre></div>
</div>
<p>The <code class="docutils literal notranslate"><span class="pre">discover</span></code> sub-command has the following options:</p>
<dl class="cmdoption">
<dt id="cmdoption-unittest-discover-v">
<code class="descname">-v</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--verbose</code><code class="descclassname"></code><a class="headerlink" href="#cmdoption-unittest-discover-v" title="Permalink to this definition">¶</a></dt>
<dd><p>Verbose output</p>
</dd></dl>

<dl class="cmdoption">
<dt id="cmdoption-unittest-discover-s">
<code class="descname">-s</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--start-directory</code><code class="descclassname"> directory</code><a class="headerlink" href="#cmdoption-unittest-discover-s" title="Permalink to this definition">¶</a></dt>
<dd><p>Directory to start discovery (<code class="docutils literal notranslate"><span class="pre">.</span></code> default)</p>
</dd></dl>

<dl class="cmdoption">
<dt id="cmdoption-unittest-discover-p">
<code class="descname">-p</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--pattern</code><code class="descclassname"> pattern</code><a class="headerlink" href="#cmdoption-unittest-discover-p" title="Permalink to this definition">¶</a></dt>
<dd><p>Pattern to match test files (<code class="docutils literal notranslate"><span class="pre">test*.py</span></code> default)</p>
</dd></dl>

<dl class="cmdoption">
<dt id="cmdoption-unittest-discover-t">
<code class="descname">-t</code><code class="descclassname"></code><code class="descclassname">, </code><code class="descname">--top-level-directory</code><code class="descclassname"> directory</code><a class="headerlink" href="#cmdoption-unittest-discover-t" title="Permalink to this definition">¶</a></dt>
<dd><p>Top level directory of project (defaults to start directory)</p>
</dd></dl>

<p>The <a class="reference internal" href="#cmdoption-unittest-discover-s"><code class="xref std std-option docutils literal notranslate"><span class="pre">-s</span></code></a>, <a class="reference internal" href="#cmdoption-unittest-discover-p"><code class="xref std std-option docutils literal notranslate"><span class="pre">-p</span></code></a>, and <a class="reference internal" href="#cmdoption-unittest-discover-t"><code class="xref std std-option docutils literal notranslate"><span class="pre">-t</span></code></a> options can be passed in
as positional arguments in that order. The following two command lines
are equivalent:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="n">discover</span> <span class="o">-</span><span class="n">s</span> <span class="n">project_directory</span> <span class="o">-</span><span class="n">p</span> <span class="s2">&quot;*_test.py&quot;</span>
<span class="n">python</span> <span class="o">-</span><span class="n">m</span> <span class="n">unittest</span> <span class="n">discover</span> <span class="n">project_directory</span> <span class="s2">&quot;*_test.py&quot;</span>
</pre></div>
</div>
<p>As well as being a path it is possible to pass a package name, for example
<code class="docutils literal notranslate"><span class="pre">myproject.subpackage.test</span></code>, as the start directory. The package name you
supply will then be imported and its location on the filesystem will be used
as the start directory.</p>
<div class="admonition caution">
<p class="admonition-title">Caution</p>
<p>Test discovery loads tests by importing them. Once test discovery has
found all the test files from the start directory you specify it turns the
paths into package names to import. For example <code class="file docutils literal notranslate"><span class="pre">foo/bar/baz.py</span></code> will be
imported as <code class="docutils literal notranslate"><span class="pre">foo.bar.baz</span></code>.</p>
<p>If you have a package installed globally and attempt test discovery on
a different copy of the package then the import <em>could</em> happen from the
wrong place. If this happens test discovery will warn you and exit.</p>
<p>If you supply the start directory as a package name rather than a
path to a directory then discover assumes that whichever location it
imports from is the location you intended, so you will not get the
warning.</p>
</div>
<p>Test modules and packages can customize test loading and discovery by through
the <a class="reference internal" href="#load-tests-protocol">load_tests protocol</a>.</p>
</div>
<div class="section" id="organizing-test-code">
<span id="organizing-tests"></span><h2>25.3.4. Organizing test code<a class="headerlink" href="#organizing-test-code" title="Permalink to this headline">¶</a></h2>
<p>The basic building blocks of unit testing are <em class="dfn">test cases</em> — single
scenarios that must be set up and checked for correctness.  In <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>,
test cases are represented by instances of <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>’s <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>
class. To make your own test cases you must write subclasses of
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>, or use <a class="reference internal" href="#unittest.FunctionTestCase" title="unittest.FunctionTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">FunctionTestCase</span></code></a>.</p>
<p>An instance of a <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>-derived class is an object that can
completely run a single test method, together with optional set-up and tidy-up
code.</p>
<p>The testing code of a <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instance should be entirely self
contained, such that it can be run either in isolation or in arbitrary
combination with any number of other test cases.</p>
<p>The simplest <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> subclass will simply override the
<code class="xref py py-meth docutils literal notranslate"><span class="pre">runTest()</span></code> method in order to perform specific testing code:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">unittest</span>

<span class="k">class</span> <span class="nc">DefaultWidgetSizeTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">runTest</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="n">widget</span> <span class="o">=</span> <span class="n">Widget</span><span class="p">(</span><span class="s1">&#39;The widget&#39;</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="n">widget</span><span class="o">.</span><span class="n">size</span><span class="p">(),</span> <span class="p">(</span><span class="mi">50</span><span class="p">,</span> <span class="mi">50</span><span class="p">),</span> <span class="s1">&#39;incorrect default size&#39;</span><span class="p">)</span>
</pre></div>
</div>
<p>Note that in order to test something, we use one of the <code class="xref py py-meth docutils literal notranslate"><span class="pre">assert*()</span></code>
methods provided by the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> base class.  If the test fails, an
exception will be raised, and <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> will identify the test case as a
<em class="dfn">failure</em>.  Any other exceptions will be treated as <em class="dfn">errors</em>. This
helps you identify where the problem is: <em class="dfn">failures</em> are caused by incorrect
results - a 5 where you expected a 6. <em class="dfn">Errors</em> are caused by incorrect
code - e.g., a <a class="reference internal" href="exceptions.html#exceptions.TypeError" title="exceptions.TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> caused by an incorrect function call.</p>
<p>The way to run a test case will be described later.  For now, note that to
construct an instance of such a test case, we call its constructor without
arguments:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">testCase</span> <span class="o">=</span> <span class="n">DefaultWidgetSizeTestCase</span><span class="p">()</span>
</pre></div>
</div>
<p>Now, such test cases can be numerous, and their set-up can be repetitive.  In
the above case, constructing a <code class="xref py py-class docutils literal notranslate"><span class="pre">Widget</span></code> in each of 100 Widget test case
subclasses would mean unsightly duplication.</p>
<p>Luckily, we can factor out such set-up code by implementing a method called
<a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a>, which the testing framework will automatically call for
us when we run the test:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">unittest</span>

<span class="k">class</span> <span class="nc">SimpleWidgetTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">setUp</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span> <span class="o">=</span> <span class="n">Widget</span><span class="p">(</span><span class="s1">&#39;The widget&#39;</span><span class="p">)</span>

<span class="k">class</span> <span class="nc">DefaultWidgetSizeTestCase</span><span class="p">(</span><span class="n">SimpleWidgetTestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">runTest</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">size</span><span class="p">(),</span> <span class="p">(</span><span class="mi">50</span><span class="p">,</span><span class="mi">50</span><span class="p">),</span>
                         <span class="s1">&#39;incorrect default size&#39;</span><span class="p">)</span>

<span class="k">class</span> <span class="nc">WidgetResizeTestCase</span><span class="p">(</span><span class="n">SimpleWidgetTestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">runTest</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">resize</span><span class="p">(</span><span class="mi">100</span><span class="p">,</span><span class="mi">150</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">size</span><span class="p">(),</span> <span class="p">(</span><span class="mi">100</span><span class="p">,</span><span class="mi">150</span><span class="p">),</span>
                         <span class="s1">&#39;wrong size after resize&#39;</span><span class="p">)</span>
</pre></div>
</div>
<p>If the <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> method raises an exception while the test is
running, the framework will consider the test to have suffered an error, and the
<code class="xref py py-meth docutils literal notranslate"><span class="pre">runTest()</span></code> method will not be executed.</p>
<p>Similarly, we can provide a <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> method that tidies up
after the <code class="xref py py-meth docutils literal notranslate"><span class="pre">runTest()</span></code> method has been run:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">unittest</span>

<span class="k">class</span> <span class="nc">SimpleWidgetTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">setUp</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span> <span class="o">=</span> <span class="n">Widget</span><span class="p">(</span><span class="s1">&#39;The widget&#39;</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">tearDown</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">dispose</span><span class="p">()</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span> <span class="o">=</span> <span class="kc">None</span>
</pre></div>
</div>
<p>If <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> succeeded, the <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> method will
be run whether <code class="xref py py-meth docutils literal notranslate"><span class="pre">runTest()</span></code> succeeded or not.</p>
<p>Such a working environment for the testing code is called a <em class="dfn">fixture</em>.</p>
<p>Often, many small test cases will use the same fixture.  In this case, we would
end up subclassing <code class="xref py py-class docutils literal notranslate"><span class="pre">SimpleWidgetTestCase</span></code> into many small one-method
classes such as <code class="xref py py-class docutils literal notranslate"><span class="pre">DefaultWidgetSizeTestCase</span></code>.  This is time-consuming and
discouraging, so in the same vein as JUnit, <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> provides a simpler
mechanism:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">unittest</span>

<span class="k">class</span> <span class="nc">WidgetTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">setUp</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span> <span class="o">=</span> <span class="n">Widget</span><span class="p">(</span><span class="s1">&#39;The widget&#39;</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">tearDown</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">dispose</span><span class="p">()</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span> <span class="o">=</span> <span class="kc">None</span>

    <span class="k">def</span> <span class="nf">test_default_size</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">size</span><span class="p">(),</span> <span class="p">(</span><span class="mi">50</span><span class="p">,</span><span class="mi">50</span><span class="p">),</span>
                         <span class="s1">&#39;incorrect default size&#39;</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">test_resize</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">resize</span><span class="p">(</span><span class="mi">100</span><span class="p">,</span><span class="mi">150</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">size</span><span class="p">(),</span> <span class="p">(</span><span class="mi">100</span><span class="p">,</span><span class="mi">150</span><span class="p">),</span>
                         <span class="s1">&#39;wrong size after resize&#39;</span><span class="p">)</span>
</pre></div>
</div>
<p>Here we have not provided a <code class="xref py py-meth docutils literal notranslate"><span class="pre">runTest()</span></code> method, but have instead
provided two different test methods.  Class instances will now each run one of
the <code class="xref py py-meth docutils literal notranslate"><span class="pre">test_*()</span></code> methods, with <code class="docutils literal notranslate"><span class="pre">self.widget</span></code> created and destroyed
separately for each instance.  When creating an instance we must specify the
test method it is to run.  We do this by passing the method name in the
constructor:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">defaultSizeTestCase</span> <span class="o">=</span> <span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_default_size&#39;</span><span class="p">)</span>
<span class="n">resizeTestCase</span> <span class="o">=</span> <span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_resize&#39;</span><span class="p">)</span>
</pre></div>
</div>
<p>Test case instances are grouped together according to the features they test.
<a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> provides a mechanism for this: the <em class="dfn">test suite</em>,
represented by <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>’s <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> class:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">widgetTestSuite</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestSuite</span><span class="p">()</span>
<span class="n">widgetTestSuite</span><span class="o">.</span><span class="n">addTest</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_default_size&#39;</span><span class="p">))</span>
<span class="n">widgetTestSuite</span><span class="o">.</span><span class="n">addTest</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_resize&#39;</span><span class="p">))</span>
</pre></div>
</div>
<p>For the ease of running tests, as we will see later, it is a good idea to
provide in each test module a callable object that returns a pre-built test
suite:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">suite</span><span class="p">():</span>
    <span class="n">suite</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestSuite</span><span class="p">()</span>
    <span class="n">suite</span><span class="o">.</span><span class="n">addTest</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_default_size&#39;</span><span class="p">))</span>
    <span class="n">suite</span><span class="o">.</span><span class="n">addTest</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_resize&#39;</span><span class="p">))</span>
    <span class="k">return</span> <span class="n">suite</span>
</pre></div>
</div>
<p>or even:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">suite</span><span class="p">():</span>
    <span class="n">tests</span> <span class="o">=</span> <span class="p">[</span><span class="s1">&#39;test_default_size&#39;</span><span class="p">,</span> <span class="s1">&#39;test_resize&#39;</span><span class="p">]</span>

    <span class="k">return</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestSuite</span><span class="p">(</span><span class="nb">map</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">,</span> <span class="n">tests</span><span class="p">))</span>
</pre></div>
</div>
<p>Since it is a common pattern to create a <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> subclass with many
similarly named test functions, <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> provides a <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a>
class that can be used to automate the process of creating a test suite and
populating it with individual tests. For example,</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">suite</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestLoader</span><span class="p">()</span><span class="o">.</span><span class="n">loadTestsFromTestCase</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">)</span>
</pre></div>
</div>
<p>will create a test suite that will run <code class="docutils literal notranslate"><span class="pre">WidgetTestCase.test_default_size()</span></code> and
<code class="docutils literal notranslate"><span class="pre">WidgetTestCase.test_resize</span></code>. <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> uses the <code class="docutils literal notranslate"><span class="pre">'test'</span></code> method
name prefix to identify test methods automatically.</p>
<p>Note that the order in which the various test cases will be run is
determined by sorting the test function names with respect to the
built-in ordering for strings.</p>
<p>Often it is desirable to group suites of test cases together, so as to run tests
for the whole system at once.  This is easy, since <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> instances
can be added to a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> just as <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances can be
added to a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">suite1</span> <span class="o">=</span> <span class="n">module1</span><span class="o">.</span><span class="n">TheTestSuite</span><span class="p">()</span>
<span class="n">suite2</span> <span class="o">=</span> <span class="n">module2</span><span class="o">.</span><span class="n">TheTestSuite</span><span class="p">()</span>
<span class="n">alltests</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestSuite</span><span class="p">([</span><span class="n">suite1</span><span class="p">,</span> <span class="n">suite2</span><span class="p">])</span>
</pre></div>
</div>
<p>You can place the definitions of test cases and test suites in the same modules
as the code they are to test (such as <code class="file docutils literal notranslate"><span class="pre">widget.py</span></code>), but there are several
advantages to placing the test code in a separate module, such as
<code class="file docutils literal notranslate"><span class="pre">test_widget.py</span></code>:</p>
<ul class="simple">
<li><p>The test module can be run standalone from the command line.</p></li>
<li><p>The test code can more easily be separated from shipped code.</p></li>
<li><p>There is less temptation to change test code to fit the code it tests without
a good reason.</p></li>
<li><p>Test code should be modified much less frequently than the code it tests.</p></li>
<li><p>Tested code can be refactored more easily.</p></li>
<li><p>Tests for modules written in C must be in separate modules anyway, so why not
be consistent?</p></li>
<li><p>If the testing strategy changes, there is no need to change the source code.</p></li>
</ul>
</div>
<div class="section" id="re-using-old-test-code">
<span id="legacy-unit-tests"></span><h2>25.3.5. Re-using old test code<a class="headerlink" href="#re-using-old-test-code" title="Permalink to this headline">¶</a></h2>
<p>Some users will find that they have existing test code that they would like to
run from <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>, without converting every old test function to a
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> subclass.</p>
<p>For this reason, <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> provides a <a class="reference internal" href="#unittest.FunctionTestCase" title="unittest.FunctionTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">FunctionTestCase</span></code></a> class.
This subclass of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> can be used to wrap an existing test
function.  Set-up and tear-down functions can also be provided.</p>
<p>Given the following test function:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">testSomething</span><span class="p">():</span>
    <span class="n">something</span> <span class="o">=</span> <span class="n">makeSomething</span><span class="p">()</span>
    <span class="k">assert</span> <span class="n">something</span><span class="o">.</span><span class="n">name</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span>
    <span class="c1"># ...</span>
</pre></div>
</div>
<p>one can create an equivalent test case instance as follows:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">testcase</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">FunctionTestCase</span><span class="p">(</span><span class="n">testSomething</span><span class="p">)</span>
</pre></div>
</div>
<p>If there are additional set-up and tear-down methods that should be called as
part of the test case’s operation, they can also be provided like so:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">testcase</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">FunctionTestCase</span><span class="p">(</span><span class="n">testSomething</span><span class="p">,</span>
                                     <span class="n">setUp</span><span class="o">=</span><span class="n">makeSomethingDB</span><span class="p">,</span>
                                     <span class="n">tearDown</span><span class="o">=</span><span class="n">deleteSomethingDB</span><span class="p">)</span>
</pre></div>
</div>
<p>To make migrating existing test suites easier, <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> supports tests
raising <a class="reference internal" href="exceptions.html#exceptions.AssertionError" title="exceptions.AssertionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AssertionError</span></code></a> to indicate test failure. However, it is
recommended that you use the explicit <code class="xref py py-meth docutils literal notranslate"><span class="pre">TestCase.fail*()</span></code> and
<code class="xref py py-meth docutils literal notranslate"><span class="pre">TestCase.assert*()</span></code> methods instead, as future versions of <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>
may treat <a class="reference internal" href="exceptions.html#exceptions.AssertionError" title="exceptions.AssertionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AssertionError</span></code></a> differently.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>Even though <a class="reference internal" href="#unittest.FunctionTestCase" title="unittest.FunctionTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">FunctionTestCase</span></code></a> can be used to quickly convert an
existing test base over to a <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>-based system, this approach is
not recommended.  Taking the time to set up proper <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>
subclasses will make future test refactorings infinitely easier.</p>
</div>
<p>In some cases, the existing tests may have been written using the <a class="reference internal" href="doctest.html#module-doctest" title="doctest: Test pieces of code within docstrings."><code class="xref py py-mod docutils literal notranslate"><span class="pre">doctest</span></code></a>
module.  If so, <a class="reference internal" href="doctest.html#module-doctest" title="doctest: Test pieces of code within docstrings."><code class="xref py py-mod docutils literal notranslate"><span class="pre">doctest</span></code></a> provides a <code class="xref py py-class docutils literal notranslate"><span class="pre">DocTestSuite</span></code> class that can
automatically build <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">unittest.TestSuite</span></code></a> instances from the existing
<a class="reference internal" href="doctest.html#module-doctest" title="doctest: Test pieces of code within docstrings."><code class="xref py py-mod docutils literal notranslate"><span class="pre">doctest</span></code></a>-based tests.</p>
</div>
<div class="section" id="skipping-tests-and-expected-failures">
<span id="unittest-skipping"></span><h2>25.3.6. Skipping tests and expected failures<a class="headerlink" href="#skipping-tests-and-expected-failures" title="Permalink to this headline">¶</a></h2>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
<p>Unittest supports skipping individual test methods and even whole classes of
tests.  In addition, it supports marking a test as an “expected failure,” a test
that is broken and will fail, but shouldn’t be counted as a failure on a
<a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a>.</p>
<p>Skipping a test is simply a matter of using the <a class="reference internal" href="#unittest.skip" title="unittest.skip"><code class="xref py py-func docutils literal notranslate"><span class="pre">skip()</span></code></a> <a class="reference internal" href="../glossary.html#term-decorator"><span class="xref std std-term">decorator</span></a>
or one of its conditional variants.</p>
<p>Basic skipping looks like this:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">MyTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>

    <span class="nd">@unittest</span><span class="o">.</span><span class="n">skip</span><span class="p">(</span><span class="s2">&quot;demonstrating skipping&quot;</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">test_nothing</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">fail</span><span class="p">(</span><span class="s2">&quot;shouldn&#39;t happen&quot;</span><span class="p">)</span>

    <span class="nd">@unittest</span><span class="o">.</span><span class="n">skipIf</span><span class="p">(</span><span class="n">mylib</span><span class="o">.</span><span class="n">__version__</span> <span class="o">&lt;</span> <span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">),</span>
                     <span class="s2">&quot;not supported in this library version&quot;</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">test_format</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="c1"># Tests that work for only a certain version of the library.</span>
        <span class="k">pass</span>

    <span class="nd">@unittest</span><span class="o">.</span><span class="n">skipUnless</span><span class="p">(</span><span class="n">sys</span><span class="o">.</span><span class="n">platform</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s2">&quot;win&quot;</span><span class="p">),</span> <span class="s2">&quot;requires Windows&quot;</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">test_windows_support</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="c1"># windows specific testing code</span>
        <span class="k">pass</span>
</pre></div>
</div>
<p>This is the output of running the example above in verbose mode:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">test_format</span> <span class="p">(</span><span class="n">__main__</span><span class="o">.</span><span class="n">MyTestCase</span><span class="p">)</span> <span class="o">...</span> <span class="n">skipped</span> <span class="s1">&#39;not supported in this library version&#39;</span>
<span class="n">test_nothing</span> <span class="p">(</span><span class="n">__main__</span><span class="o">.</span><span class="n">MyTestCase</span><span class="p">)</span> <span class="o">...</span> <span class="n">skipped</span> <span class="s1">&#39;demonstrating skipping&#39;</span>
<span class="n">test_windows_support</span> <span class="p">(</span><span class="n">__main__</span><span class="o">.</span><span class="n">MyTestCase</span><span class="p">)</span> <span class="o">...</span> <span class="n">skipped</span> <span class="s1">&#39;requires Windows&#39;</span>

<span class="o">----------------------------------------------------------------------</span>
<span class="n">Ran</span> <span class="mi">3</span> <span class="n">tests</span> <span class="ow">in</span> <span class="mf">0.005</span><span class="n">s</span>

<span class="n">OK</span> <span class="p">(</span><span class="n">skipped</span><span class="o">=</span><span class="mi">3</span><span class="p">)</span>
</pre></div>
</div>
<p>Classes can be skipped just like methods:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="nd">@unittest</span><span class="o">.</span><span class="n">skip</span><span class="p">(</span><span class="s2">&quot;showing class skipping&quot;</span><span class="p">)</span>
<span class="k">class</span> <span class="nc">MySkippedTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">test_not_run</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">pass</span>
</pre></div>
</div>
<p><a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestCase.setUp()</span></code></a> can also skip the test.  This is useful when a resource
that needs to be set up is not available.</p>
<p>Expected failures use the <a class="reference internal" href="#unittest.expectedFailure" title="unittest.expectedFailure"><code class="xref py py-func docutils literal notranslate"><span class="pre">expectedFailure()</span></code></a> decorator.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">ExpectedFailureTestCase</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="nd">@unittest</span><span class="o">.</span><span class="n">expectedFailure</span>
    <span class="k">def</span> <span class="nf">test_fail</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="s2">&quot;broken&quot;</span><span class="p">)</span>
</pre></div>
</div>
<p>It’s easy to roll your own skipping decorators by making a decorator that calls
<a class="reference internal" href="#unittest.skip" title="unittest.skip"><code class="xref py py-func docutils literal notranslate"><span class="pre">skip()</span></code></a> on the test when it wants it to be skipped.  This decorator skips
the test unless the passed object has a certain attribute:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">skipUnlessHasattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">attr</span><span class="p">):</span>
    <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">attr</span><span class="p">):</span>
        <span class="k">return</span> <span class="k">lambda</span> <span class="n">func</span><span class="p">:</span> <span class="n">func</span>
    <span class="k">return</span> <span class="n">unittest</span><span class="o">.</span><span class="n">skip</span><span class="p">(</span><span class="s2">&quot;</span><span class="si">{!r}</span><span class="s2"> doesn&#39;t have </span><span class="si">{!r}</span><span class="s2">&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">attr</span><span class="p">))</span>
</pre></div>
</div>
<p>The following decorators implement test skipping and expected failures:</p>
<dl class="function">
<dt id="unittest.skip">
<code class="descclassname">unittest.</code><code class="descname">skip</code><span class="sig-paren">(</span><em>reason</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.skip" title="Permalink to this definition">¶</a></dt>
<dd><p>Unconditionally skip the decorated test.  <em>reason</em> should describe why the
test is being skipped.</p>
</dd></dl>

<dl class="function">
<dt id="unittest.skipIf">
<code class="descclassname">unittest.</code><code class="descname">skipIf</code><span class="sig-paren">(</span><em>condition</em>, <em>reason</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.skipIf" title="Permalink to this definition">¶</a></dt>
<dd><p>Skip the decorated test if <em>condition</em> is true.</p>
</dd></dl>

<dl class="function">
<dt id="unittest.skipUnless">
<code class="descclassname">unittest.</code><code class="descname">skipUnless</code><span class="sig-paren">(</span><em>condition</em>, <em>reason</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.skipUnless" title="Permalink to this definition">¶</a></dt>
<dd><p>Skip the decorated test unless <em>condition</em> is true.</p>
</dd></dl>

<dl class="function">
<dt id="unittest.expectedFailure">
<code class="descclassname">unittest.</code><code class="descname">expectedFailure</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.expectedFailure" title="Permalink to this definition">¶</a></dt>
<dd><p>Mark the test as an expected failure.  If the test fails when run, the test
is not counted as a failure.</p>
</dd></dl>

<dl class="exception">
<dt id="unittest.SkipTest">
<em class="property">exception </em><code class="descclassname">unittest.</code><code class="descname">SkipTest</code><span class="sig-paren">(</span><em>reason</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.SkipTest" title="Permalink to this definition">¶</a></dt>
<dd><p>This exception is raised to skip a test.</p>
<p>Usually you can use <a class="reference internal" href="#unittest.TestCase.skipTest" title="unittest.TestCase.skipTest"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestCase.skipTest()</span></code></a> or one of the skipping
decorators instead of raising this directly.</p>
</dd></dl>

<p>Skipped tests will not have <code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code> or <code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code> run around them.
Skipped classes will not have <code class="xref py py-meth docutils literal notranslate"><span class="pre">setUpClass()</span></code> or <code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDownClass()</span></code> run.</p>
</div>
<div class="section" id="classes-and-functions">
<span id="unittest-contents"></span><h2>25.3.7. Classes and functions<a class="headerlink" href="#classes-and-functions" title="Permalink to this headline">¶</a></h2>
<p>This section describes in depth the API of <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>.</p>
<div class="section" id="test-cases">
<span id="testcase-objects"></span><h3>25.3.7.1. Test cases<a class="headerlink" href="#test-cases" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="unittest.TestCase">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">TestCase</code><span class="sig-paren">(</span><em>methodName='runTest'</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase" title="Permalink to this definition">¶</a></dt>
<dd><p>Instances of the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> class represent the smallest testable units
in the <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> universe.  This class is intended to be used as a base
class, with specific tests being implemented by concrete subclasses.  This class
implements the interface needed by the test runner to allow it to drive the
test, and methods that the test code can use to check for and report various
kinds of failure.</p>
<p>Each instance of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> will run a single test method: the method
named <em>methodName</em>.  If you remember, we had an earlier example that went
something like this:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">suite</span><span class="p">():</span>
    <span class="n">suite</span> <span class="o">=</span> <span class="n">unittest</span><span class="o">.</span><span class="n">TestSuite</span><span class="p">()</span>
    <span class="n">suite</span><span class="o">.</span><span class="n">addTest</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_default_size&#39;</span><span class="p">))</span>
    <span class="n">suite</span><span class="o">.</span><span class="n">addTest</span><span class="p">(</span><span class="n">WidgetTestCase</span><span class="p">(</span><span class="s1">&#39;test_resize&#39;</span><span class="p">))</span>
    <span class="k">return</span> <span class="n">suite</span>
</pre></div>
</div>
<p>Here, we create two instances of <code class="xref py py-class docutils literal notranslate"><span class="pre">WidgetTestCase</span></code>, each of which runs a
single test.</p>
<p><em>methodName</em> defaults to <code class="xref py py-meth docutils literal notranslate"><span class="pre">runTest()</span></code>.</p>
<p><a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances provide three groups of methods: one group used
to run the test, another used by the test implementation to check conditions
and report failures, and some inquiry methods allowing information about the
test itself to be gathered.</p>
<p>Methods in the first group (running the test) are:</p>
<dl class="method">
<dt id="unittest.TestCase.setUp">
<code class="descname">setUp</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.setUp" title="Permalink to this definition">¶</a></dt>
<dd><p>Method called to prepare the test fixture.  This is called immediately
before calling the test method; other than <a class="reference internal" href="exceptions.html#exceptions.AssertionError" title="exceptions.AssertionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AssertionError</span></code></a> or <a class="reference internal" href="#unittest.SkipTest" title="unittest.SkipTest"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SkipTest</span></code></a>,
any exception raised by this method will be considered an error rather than
a test failure. The default implementation does nothing.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.tearDown">
<code class="descname">tearDown</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.tearDown" title="Permalink to this definition">¶</a></dt>
<dd><p>Method called immediately after the test method has been called and the
result recorded.  This is called even if the test method raised an
exception, so the implementation in subclasses may need to be particularly
careful about checking internal state.  Any exception, other than
<a class="reference internal" href="exceptions.html#exceptions.AssertionError" title="exceptions.AssertionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AssertionError</span></code></a> or <a class="reference internal" href="#unittest.SkipTest" title="unittest.SkipTest"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SkipTest</span></code></a>, raised by this method will be
considered an additional error rather than a test failure (thus increasing
the total number of reported errors). This method will only be called if
the <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> succeeds, regardless of the outcome of the test method.
The default implementation does nothing.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.setUpClass">
<code class="descname">setUpClass</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.setUpClass" title="Permalink to this definition">¶</a></dt>
<dd><p>A class method called before tests in an individual class are run.
<code class="docutils literal notranslate"><span class="pre">setUpClass</span></code> is called with the class as the only argument
and must be decorated as a <a class="reference internal" href="functions.html#classmethod" title="classmethod"><code class="xref py py-func docutils literal notranslate"><span class="pre">classmethod()</span></code></a>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="nd">@classmethod</span>
<span class="k">def</span> <span class="nf">setUpClass</span><span class="p">(</span><span class="bp">cls</span><span class="p">):</span>
    <span class="o">...</span>
</pre></div>
</div>
<p>See <a class="reference internal" href="#class-and-module-fixtures">Class and Module Fixtures</a> for more details.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.tearDownClass">
<code class="descname">tearDownClass</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.tearDownClass" title="Permalink to this definition">¶</a></dt>
<dd><p>A class method called after tests in an individual class have run.
<code class="docutils literal notranslate"><span class="pre">tearDownClass</span></code> is called with the class as the only argument
and must be decorated as a <a class="reference internal" href="functions.html#classmethod" title="classmethod"><code class="xref py py-meth docutils literal notranslate"><span class="pre">classmethod()</span></code></a>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="nd">@classmethod</span>
<span class="k">def</span> <span class="nf">tearDownClass</span><span class="p">(</span><span class="bp">cls</span><span class="p">):</span>
    <span class="o">...</span>
</pre></div>
</div>
<p>See <a class="reference internal" href="#class-and-module-fixtures">Class and Module Fixtures</a> for more details.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.run">
<code class="descname">run</code><span class="sig-paren">(</span><em>result=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.run" title="Permalink to this definition">¶</a></dt>
<dd><p>Run the test, collecting the result into the test result object passed as
<em>result</em>.  If <em>result</em> is omitted or <code class="docutils literal notranslate"><span class="pre">None</span></code>, a temporary result
object is created (by calling the <a class="reference internal" href="#unittest.TestCase.defaultTestResult" title="unittest.TestCase.defaultTestResult"><code class="xref py py-meth docutils literal notranslate"><span class="pre">defaultTestResult()</span></code></a> method) and
used. The result object is not returned to <a class="reference internal" href="#unittest.TestCase.run" title="unittest.TestCase.run"><code class="xref py py-meth docutils literal notranslate"><span class="pre">run()</span></code></a>’s caller.</p>
<p>The same effect may be had by simply calling the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>
instance.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.skipTest">
<code class="descname">skipTest</code><span class="sig-paren">(</span><em>reason</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.skipTest" title="Permalink to this definition">¶</a></dt>
<dd><p>Calling this during a test method or <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> skips the current
test.  See <a class="reference internal" href="#unittest-skipping"><span class="std std-ref">Skipping tests and expected failures</span></a> for more information.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.debug">
<code class="descname">debug</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.debug" title="Permalink to this definition">¶</a></dt>
<dd><p>Run the test without collecting the result.  This allows exceptions raised
by the test to be propagated to the caller, and can be used to support
running tests under a debugger.</p>
</dd></dl>

<p id="assert-methods">The <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> class provides several assert methods to check for and
report failures.  The following table lists the most commonly used methods
(see the tables below for more assert methods):</p>
<table class="docutils align-center">
<colgroup>
<col style="width: 48%" />
<col style="width: 34%" />
<col style="width: 18%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Method</p></th>
<th class="head"><p>Checks that</p></th>
<th class="head"><p>New in</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">==</span> <span class="pre">b</span></code></p></td>
<td></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotEqual" title="unittest.TestCase.assertNotEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">!=</span> <span class="pre">b</span></code></p></td>
<td></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTrue(x)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">bool(x)</span> <span class="pre">is</span> <span class="pre">True</span></code></p></td>
<td></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertFalse" title="unittest.TestCase.assertFalse"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertFalse(x)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">bool(x)</span> <span class="pre">is</span> <span class="pre">False</span></code></p></td>
<td></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertIs" title="unittest.TestCase.assertIs"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertIs(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">is</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertIsNot" title="unittest.TestCase.assertIsNot"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertIsNot(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">is</span> <span class="pre">not</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertIsNone" title="unittest.TestCase.assertIsNone"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertIsNone(x)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre">is</span> <span class="pre">None</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertIsNotNone" title="unittest.TestCase.assertIsNotNone"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertIsNotNone(x)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre">is</span> <span class="pre">not</span> <span class="pre">None</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertIn" title="unittest.TestCase.assertIn"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertIn(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">in</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotIn" title="unittest.TestCase.assertNotIn"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotIn(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">not</span> <span class="pre">in</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertIsInstance" title="unittest.TestCase.assertIsInstance"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertIsInstance(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">isinstance(a,</span> <span class="pre">b)</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotIsInstance" title="unittest.TestCase.assertNotIsInstance"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotIsInstance(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">not</span> <span class="pre">isinstance(a,</span> <span class="pre">b)</span></code></p></td>
<td><p>2.7</p></td>
</tr>
</tbody>
</table>
<p>All the assert methods (except <a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a>,
<a class="reference internal" href="#unittest.TestCase.assertRaisesRegexp" title="unittest.TestCase.assertRaisesRegexp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaisesRegexp()</span></code></a>)
accept a <em>msg</em> argument that, if specified, is used as the error message on
failure (see also <a class="reference internal" href="#unittest.TestCase.longMessage" title="unittest.TestCase.longMessage"><code class="xref py py-data docutils literal notranslate"><span class="pre">longMessage</span></code></a>).</p>
<dl class="method">
<dt id="unittest.TestCase.assertEqual">
<code class="descname">assertEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>first</em> and <em>second</em> are equal.  If the values do not compare
equal, the test will fail.</p>
<p>In addition, if <em>first</em> and <em>second</em> are the exact same type and one of
list, tuple, dict, set, frozenset or unicode or any type that a subclass
registers with <a class="reference internal" href="#unittest.TestCase.addTypeEqualityFunc" title="unittest.TestCase.addTypeEqualityFunc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">addTypeEqualityFunc()</span></code></a> the type-specific equality
function will be called in order to generate a more useful default
error message (see also the <a class="reference internal" href="#type-specific-methods"><span class="std std-ref">list of type-specific methods</span></a>).</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span>Added the automatic calling of type-specific equality function.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertNotEqual">
<code class="descname">assertNotEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertNotEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>first</em> and <em>second</em> are not equal.  If the values do compare
equal, the test will fail.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertTrue">
<code class="descname">assertTrue</code><span class="sig-paren">(</span><em>expr</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertTrue" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertFalse">
<code class="descname">assertFalse</code><span class="sig-paren">(</span><em>expr</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertFalse" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>expr</em> is true (or false).</p>
<p>Note that this is equivalent to <code class="docutils literal notranslate"><span class="pre">bool(expr)</span> <span class="pre">is</span> <span class="pre">True</span></code> and not to <code class="docutils literal notranslate"><span class="pre">expr</span>
<span class="pre">is</span> <span class="pre">True</span></code> (use <code class="docutils literal notranslate"><span class="pre">assertIs(expr,</span> <span class="pre">True)</span></code> for the latter).  This method
should also be avoided when more specific methods are available (e.g.
<code class="docutils literal notranslate"><span class="pre">assertEqual(a,</span> <span class="pre">b)</span></code> instead of <code class="docutils literal notranslate"><span class="pre">assertTrue(a</span> <span class="pre">==</span> <span class="pre">b)</span></code>), because they
provide a better error message in case of failure.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertIs">
<code class="descname">assertIs</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertIs" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertIsNot">
<code class="descname">assertIsNot</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertIsNot" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>first</em> and <em>second</em> evaluate (or don’t evaluate) to the same object.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertIsNone">
<code class="descname">assertIsNone</code><span class="sig-paren">(</span><em>expr</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertIsNone" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertIsNotNone">
<code class="descname">assertIsNotNone</code><span class="sig-paren">(</span><em>expr</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertIsNotNone" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>expr</em> is (or is not) <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertIn">
<code class="descname">assertIn</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertIn" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertNotIn">
<code class="descname">assertNotIn</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertNotIn" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>first</em> is (or is not) in <em>second</em>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertIsInstance">
<code class="descname">assertIsInstance</code><span class="sig-paren">(</span><em>obj</em>, <em>cls</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertIsInstance" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertNotIsInstance">
<code class="descname">assertNotIsInstance</code><span class="sig-paren">(</span><em>obj</em>, <em>cls</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertNotIsInstance" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>obj</em> is (or is not) an instance of <em>cls</em> (which can be a
class or a tuple of classes, as supported by <a class="reference internal" href="functions.html#isinstance" title="isinstance"><code class="xref py py-func docutils literal notranslate"><span class="pre">isinstance()</span></code></a>).
To check for the exact type, use <a class="reference internal" href="#unittest.TestCase.assertIs" title="unittest.TestCase.assertIs"><code class="xref py py-func docutils literal notranslate"><span class="pre">assertIs(type(obj),</span> <span class="pre">cls)</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<p>It is also possible to check that exceptions and warnings are raised using
the following methods:</p>
<table class="docutils align-center">
<colgroup>
<col style="width: 53%" />
<col style="width: 36%" />
<col style="width: 11%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Method</p></th>
<th class="head"><p>Checks that</p></th>
<th class="head"><p>New in</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises(exc,</span> <span class="pre">fun,</span> <span class="pre">*args,</span> <span class="pre">**kwds)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">fun(*args,</span> <span class="pre">**kwds)</span></code> raises <em>exc</em></p></td>
<td></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertRaisesRegexp" title="unittest.TestCase.assertRaisesRegexp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaisesRegexp(exc,</span> <span class="pre">r,</span> <span class="pre">fun,</span> <span class="pre">*args,</span> <span class="pre">**kwds)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">fun(*args,</span> <span class="pre">**kwds)</span></code> raises <em>exc</em>
and the message matches regex <em>r</em></p></td>
<td><p>2.7</p></td>
</tr>
</tbody>
</table>
<dl class="method">
<dt id="unittest.TestCase.assertRaises">
<code class="descname">assertRaises</code><span class="sig-paren">(</span><em>exception</em>, <em>callable</em>, <em>*args</em>, <em>**kwds</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertRaises" title="Permalink to this definition">¶</a></dt>
<dt>
<code class="descname">assertRaises</code><span class="sig-paren">(</span><em>exception</em><span class="sig-paren">)</span></dt>
<dd><p>Test that an exception is raised when <em>callable</em> is called with any
positional or keyword arguments that are also passed to
<a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a>.  The test passes if <em>exception</em> is raised, is an
error if another exception is raised, or fails if no exception is raised.
To catch any of a group of exceptions, a tuple containing the exception
classes may be passed as <em>exception</em>.</p>
<p>If only the <em>exception</em> argument is given, returns a context manager so
that the code under test can be written inline rather than as a function:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">assertRaises</span><span class="p">(</span><span class="n">SomeException</span><span class="p">):</span>
    <span class="n">do_something</span><span class="p">()</span>
</pre></div>
</div>
<p>The context manager will store the caught exception object in its
<code class="xref py py-attr docutils literal notranslate"><span class="pre">exception</span></code> attribute.  This can be useful if the intention
is to perform additional checks on the exception raised:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">assertRaises</span><span class="p">(</span><span class="n">SomeException</span><span class="p">)</span> <span class="k">as</span> <span class="n">cm</span><span class="p">:</span>
    <span class="n">do_something</span><span class="p">()</span>

<span class="n">the_exception</span> <span class="o">=</span> <span class="n">cm</span><span class="o">.</span><span class="n">exception</span>
<span class="bp">self</span><span class="o">.</span><span class="n">assertEqual</span><span class="p">(</span><span class="n">the_exception</span><span class="o">.</span><span class="n">error_code</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
</pre></div>
</div>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span>Added the ability to use <a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a> as a context manager.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertRaisesRegexp">
<code class="descname">assertRaisesRegexp</code><span class="sig-paren">(</span><em>exception</em>, <em>regexp</em>, <em>callable</em>, <em>*args</em>, <em>**kwds</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertRaisesRegexp" title="Permalink to this definition">¶</a></dt>
<dt>
<code class="descname">assertRaisesRegexp</code><span class="sig-paren">(</span><em>exception</em>, <em>regexp</em><span class="sig-paren">)</span></dt>
<dd><p>Like <a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a> but also tests that <em>regexp</em> matches
on the string representation of the raised exception.  <em>regexp</em> may be
a regular expression object or a string containing a regular expression
suitable for use by <a class="reference internal" href="re.html#re.search" title="re.search"><code class="xref py py-func docutils literal notranslate"><span class="pre">re.search()</span></code></a>.  Examples:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="bp">self</span><span class="o">.</span><span class="n">assertRaisesRegexp</span><span class="p">(</span><span class="ne">ValueError</span><span class="p">,</span> <span class="s2">&quot;invalid literal for.*XYZ&#39;$&quot;</span><span class="p">,</span>
                        <span class="nb">int</span><span class="p">,</span> <span class="s1">&#39;XYZ&#39;</span><span class="p">)</span>
</pre></div>
</div>
<p>or:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">assertRaisesRegexp</span><span class="p">(</span><span class="ne">ValueError</span><span class="p">,</span> <span class="s1">&#39;literal&#39;</span><span class="p">):</span>
   <span class="nb">int</span><span class="p">(</span><span class="s1">&#39;XYZ&#39;</span><span class="p">)</span>
</pre></div>
</div>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<p>There are also other methods used to perform more specific checks, such as:</p>
<table class="docutils align-center">
<colgroup>
<col style="width: 46%" />
<col style="width: 38%" />
<col style="width: 16%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Method</p></th>
<th class="head"><p>Checks that</p></th>
<th class="head"><p>New in</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertAlmostEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">round(a-b,</span> <span class="pre">7)</span> <span class="pre">==</span> <span class="pre">0</span></code></p></td>
<td></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotAlmostEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">round(a-b,</span> <span class="pre">7)</span> <span class="pre">!=</span> <span class="pre">0</span></code></p></td>
<td></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertGreater" title="unittest.TestCase.assertGreater"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertGreater(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">&gt;</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertGreaterEqual" title="unittest.TestCase.assertGreaterEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertGreaterEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">&gt;=</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertLess" title="unittest.TestCase.assertLess"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertLess(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">&lt;</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertLessEqual" title="unittest.TestCase.assertLessEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertLessEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">a</span> <span class="pre">&lt;=</span> <span class="pre">b</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertRegexpMatches" title="unittest.TestCase.assertRegexpMatches"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRegexpMatches(s,</span> <span class="pre">r)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">r.search(s)</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotRegexpMatches" title="unittest.TestCase.assertNotRegexpMatches"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotRegexpMatches(s,</span> <span class="pre">r)</span></code></a></p></td>
<td><p><code class="docutils literal notranslate"><span class="pre">not</span> <span class="pre">r.search(s)</span></code></p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertItemsEqual" title="unittest.TestCase.assertItemsEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertItemsEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>sorted(a) == sorted(b) and
works with unhashable objs</p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertDictContainsSubset" title="unittest.TestCase.assertDictContainsSubset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertDictContainsSubset(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>all the key/value pairs
in <em>a</em> exist in <em>b</em></p></td>
<td><p>2.7</p></td>
</tr>
</tbody>
</table>
<dl class="method">
<dt id="unittest.TestCase.assertAlmostEqual">
<code class="descname">assertAlmostEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>places=7</em>, <em>msg=None</em>, <em>delta=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertAlmostEqual" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertNotAlmostEqual">
<code class="descname">assertNotAlmostEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>places=7</em>, <em>msg=None</em>, <em>delta=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertNotAlmostEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>first</em> and <em>second</em> are approximately (or not approximately)
equal by computing the difference, rounding to the given number of
decimal <em>places</em> (default 7), and comparing to zero.  Note that these
methods round the values to the given number of <em>decimal places</em> (i.e.
like the <a class="reference internal" href="functions.html#round" title="round"><code class="xref py py-func docutils literal notranslate"><span class="pre">round()</span></code></a> function) and not <em>significant digits</em>.</p>
<p>If <em>delta</em> is supplied instead of <em>places</em> then the difference
between <em>first</em> and <em>second</em> must be less or equal to (or greater than) <em>delta</em>.</p>
<p>Supplying both <em>delta</em> and <em>places</em> raises a <code class="docutils literal notranslate"><span class="pre">TypeError</span></code>.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span><a class="reference internal" href="#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertAlmostEqual()</span></code></a> automatically considers almost equal objects
that compare equal.  <a class="reference internal" href="#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotAlmostEqual()</span></code></a> automatically fails
if the objects compare equal.  Added the <em>delta</em> keyword argument.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertGreater">
<code class="descname">assertGreater</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertGreater" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertGreaterEqual">
<code class="descname">assertGreaterEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertGreaterEqual" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertLess">
<code class="descname">assertLess</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertLess" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertLessEqual">
<code class="descname">assertLessEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertLessEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that <em>first</em> is respectively &gt;, &gt;=, &lt; or &lt;= than <em>second</em> depending
on the method name.  If not, the test will fail:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="bp">self</span><span class="o">.</span><span class="n">assertGreaterEqual</span><span class="p">(</span><span class="mi">3</span><span class="p">,</span> <span class="mi">4</span><span class="p">)</span>
<span class="go">AssertionError: &quot;3&quot; unexpectedly not greater than or equal to &quot;4&quot;</span>
</pre></div>
</div>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertRegexpMatches">
<code class="descname">assertRegexpMatches</code><span class="sig-paren">(</span><em>text</em>, <em>regexp</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertRegexpMatches" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that a <em>regexp</em> search matches <em>text</em>.  In case
of failure, the error message will include the pattern and the <em>text</em> (or
the pattern and the part of <em>text</em> that unexpectedly matched).  <em>regexp</em>
may be a regular expression object or a string containing a regular
expression suitable for use by <a class="reference internal" href="re.html#re.search" title="re.search"><code class="xref py py-func docutils literal notranslate"><span class="pre">re.search()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertNotRegexpMatches">
<code class="descname">assertNotRegexpMatches</code><span class="sig-paren">(</span><em>text</em>, <em>regexp</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertNotRegexpMatches" title="Permalink to this definition">¶</a></dt>
<dd><p>Verifies that a <em>regexp</em> search does not match <em>text</em>.  Fails with an error
message including the pattern and the part of <em>text</em> that matches.  <em>regexp</em>
may be a regular expression object or a string containing a regular
expression suitable for use by <a class="reference internal" href="re.html#re.search" title="re.search"><code class="xref py py-func docutils literal notranslate"><span class="pre">re.search()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertItemsEqual">
<code class="descname">assertItemsEqual</code><span class="sig-paren">(</span><em>actual</em>, <em>expected</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertItemsEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that sequence <em>expected</em> contains the same elements as <em>actual</em>,
regardless of their order. When they don’t, an error message listing the
differences between the sequences will be generated.</p>
<p>Duplicate elements are <em>not</em> ignored when comparing <em>actual</em> and
<em>expected</em>. It verifies if each element has the same count in both
sequences. It is the equivalent of <code class="docutils literal notranslate"><span class="pre">assertEqual(sorted(expected),</span>
<span class="pre">sorted(actual))</span></code> but it works with sequences of unhashable objects as
well.</p>
<p>In Python 3, this method is named <code class="docutils literal notranslate"><span class="pre">assertCountEqual</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertDictContainsSubset">
<code class="descname">assertDictContainsSubset</code><span class="sig-paren">(</span><em>expected</em>, <em>actual</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertDictContainsSubset" title="Permalink to this definition">¶</a></dt>
<dd><p>Tests whether the key/value pairs in dictionary <em>actual</em> are a
superset of those in <em>expected</em>.  If not, an error message listing
the missing keys and mismatched values is generated.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
<div class="deprecated">
<p><span class="versionmodified deprecated">Deprecated since version 3.2.</span></p>
</div>
</dd></dl>

<p id="type-specific-methods">The <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a> method dispatches the equality check for objects of
the same type to different type-specific methods.  These methods are already
implemented for most of the built-in types, but it’s also possible to
register new methods using <a class="reference internal" href="#unittest.TestCase.addTypeEqualityFunc" title="unittest.TestCase.addTypeEqualityFunc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">addTypeEqualityFunc()</span></code></a>:</p>
<dl class="method">
<dt id="unittest.TestCase.addTypeEqualityFunc">
<code class="descname">addTypeEqualityFunc</code><span class="sig-paren">(</span><em>typeobj</em>, <em>function</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.addTypeEqualityFunc" title="Permalink to this definition">¶</a></dt>
<dd><p>Registers a type-specific method called by <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a> to check
if two objects of exactly the same <em>typeobj</em> (not subclasses) compare
equal.  <em>function</em> must take two positional arguments and a third msg=None
keyword argument just as <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a> does.  It must raise
<a class="reference internal" href="#unittest.TestCase.failureException" title="unittest.TestCase.failureException"><code class="xref py py-data docutils literal notranslate"><span class="pre">self.failureException(msg)</span></code></a> when inequality
between the first two parameters is detected – possibly providing useful
information and explaining the inequalities in details in the error
message.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<p>The list of type-specific methods automatically used by
<a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a> are summarized in the following table.  Note
that it’s usually not necessary to invoke these methods directly.</p>
<table class="docutils align-center">
<colgroup>
<col style="width: 49%" />
<col style="width: 35%" />
<col style="width: 17%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Method</p></th>
<th class="head"><p>Used to compare</p></th>
<th class="head"><p>New in</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertMultiLineEqual" title="unittest.TestCase.assertMultiLineEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertMultiLineEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>strings</p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertSequenceEqual" title="unittest.TestCase.assertSequenceEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertSequenceEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>sequences</p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertListEqual" title="unittest.TestCase.assertListEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertListEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>lists</p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertTupleEqual" title="unittest.TestCase.assertTupleEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTupleEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>tuples</p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertSetEqual" title="unittest.TestCase.assertSetEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertSetEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>sets or frozensets</p></td>
<td><p>2.7</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertDictEqual" title="unittest.TestCase.assertDictEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertDictEqual(a,</span> <span class="pre">b)</span></code></a></p></td>
<td><p>dicts</p></td>
<td><p>2.7</p></td>
</tr>
</tbody>
</table>
<dl class="method">
<dt id="unittest.TestCase.assertMultiLineEqual">
<code class="descname">assertMultiLineEqual</code><span class="sig-paren">(</span><em>first</em>, <em>second</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertMultiLineEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that the multiline string <em>first</em> is equal to the string <em>second</em>.
When not equal a diff of the two strings highlighting the differences
will be included in the error message. This method is used by default
when comparing Unicode strings with <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertSequenceEqual">
<code class="descname">assertSequenceEqual</code><span class="sig-paren">(</span><em>seq1</em>, <em>seq2</em>, <em>msg=None</em>, <em>seq_type=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertSequenceEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Tests that two sequences are equal.  If a <em>seq_type</em> is supplied, both
<em>seq1</em> and <em>seq2</em> must be instances of <em>seq_type</em> or a failure will
be raised.  If the sequences are different an error message is
constructed that shows the difference between the two.</p>
<p>This method is not called directly by <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a>, but
it’s used to implement <a class="reference internal" href="#unittest.TestCase.assertListEqual" title="unittest.TestCase.assertListEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertListEqual()</span></code></a> and
<a class="reference internal" href="#unittest.TestCase.assertTupleEqual" title="unittest.TestCase.assertTupleEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTupleEqual()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertListEqual">
<code class="descname">assertListEqual</code><span class="sig-paren">(</span><em>list1</em>, <em>list2</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertListEqual" title="Permalink to this definition">¶</a></dt>
<dt id="unittest.TestCase.assertTupleEqual">
<code class="descname">assertTupleEqual</code><span class="sig-paren">(</span><em>tuple1</em>, <em>tuple2</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertTupleEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Tests that two lists or tuples are equal.  If not, an error message is
constructed that shows only the differences between the two.  An error
is also raised if either of the parameters are of the wrong type.
These methods are used by default when comparing lists or tuples with
<a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertSetEqual">
<code class="descname">assertSetEqual</code><span class="sig-paren">(</span><em>set1</em>, <em>set2</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertSetEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Tests that two sets are equal.  If not, an error message is constructed
that lists the differences between the sets.  This method is used by
default when comparing sets or frozensets with <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a>.</p>
<p>Fails if either of <em>set1</em> or <em>set2</em> does not have a <code class="xref py py-meth docutils literal notranslate"><span class="pre">set.difference()</span></code>
method.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.assertDictEqual">
<code class="descname">assertDictEqual</code><span class="sig-paren">(</span><em>expected</em>, <em>actual</em>, <em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.assertDictEqual" title="Permalink to this definition">¶</a></dt>
<dd><p>Test that two dictionaries are equal.  If not, an error message is
constructed that shows the differences in the dictionaries. This
method will be used by default to compare dictionaries in
calls to <a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<p id="other-methods-and-attrs">Finally the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> provides the following methods and attributes:</p>
<dl class="method">
<dt id="unittest.TestCase.fail">
<code class="descname">fail</code><span class="sig-paren">(</span><em>msg=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.fail" title="Permalink to this definition">¶</a></dt>
<dd><p>Signals a test failure unconditionally, with <em>msg</em> or <code class="docutils literal notranslate"><span class="pre">None</span></code> for
the error message.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestCase.failureException">
<code class="descname">failureException</code><a class="headerlink" href="#unittest.TestCase.failureException" title="Permalink to this definition">¶</a></dt>
<dd><p>This class attribute gives the exception raised by the test method.  If a
test framework needs to use a specialized exception, possibly to carry
additional information, it must subclass this exception in order to “play
fair” with the framework.  The initial value of this attribute is
<a class="reference internal" href="exceptions.html#exceptions.AssertionError" title="exceptions.AssertionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AssertionError</span></code></a>.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestCase.longMessage">
<code class="descname">longMessage</code><a class="headerlink" href="#unittest.TestCase.longMessage" title="Permalink to this definition">¶</a></dt>
<dd><p>If set to <code class="docutils literal notranslate"><span class="pre">True</span></code> then any explicit failure message you pass in to the
<a class="reference internal" href="#assert-methods"><span class="std std-ref">assert methods</span></a> will be appended to the end of the
normal failure message.  The normal messages contain useful information
about the objects involved, for example the message from assertEqual
shows you the repr of the two unequal objects. Setting this attribute
to <code class="docutils literal notranslate"><span class="pre">True</span></code> allows you to have a custom error message in addition to the
normal one.</p>
<p>This attribute defaults to <code class="docutils literal notranslate"><span class="pre">False</span></code>, meaning that a custom message passed
to an assert method will silence the normal message.</p>
<p>The class setting can be overridden in individual tests by assigning an
instance attribute to <code class="docutils literal notranslate"><span class="pre">True</span></code> or <code class="docutils literal notranslate"><span class="pre">False</span></code> before calling the assert methods.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestCase.maxDiff">
<code class="descname">maxDiff</code><a class="headerlink" href="#unittest.TestCase.maxDiff" title="Permalink to this definition">¶</a></dt>
<dd><p>This attribute controls the maximum length of diffs output by assert
methods that report diffs on failure. It defaults to 80*8 characters.
Assert methods affected by this attribute are
<a class="reference internal" href="#unittest.TestCase.assertSequenceEqual" title="unittest.TestCase.assertSequenceEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertSequenceEqual()</span></code></a> (including all the sequence comparison
methods that delegate to it), <a class="reference internal" href="#unittest.TestCase.assertDictEqual" title="unittest.TestCase.assertDictEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertDictEqual()</span></code></a> and
<a class="reference internal" href="#unittest.TestCase.assertMultiLineEqual" title="unittest.TestCase.assertMultiLineEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertMultiLineEqual()</span></code></a>.</p>
<p>Setting <code class="docutils literal notranslate"><span class="pre">maxDiff</span></code> to <code class="docutils literal notranslate"><span class="pre">None</span></code> means that there is no maximum length of
diffs.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<p>Testing frameworks can use the following methods to collect information on
the test:</p>
<dl class="method">
<dt id="unittest.TestCase.countTestCases">
<code class="descname">countTestCases</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.countTestCases" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of tests represented by this test object.  For
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances, this will always be <code class="docutils literal notranslate"><span class="pre">1</span></code>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.defaultTestResult">
<code class="descname">defaultTestResult</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.defaultTestResult" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an instance of the test result class that should be used for this
test case class (if no other result instance is provided to the
<a class="reference internal" href="#unittest.TestCase.run" title="unittest.TestCase.run"><code class="xref py py-meth docutils literal notranslate"><span class="pre">run()</span></code></a> method).</p>
<p>For <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances, this will always be an instance of
<a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a>; subclasses of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> should override this
as necessary.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.id">
<code class="descname">id</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.id" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a string identifying the specific test case.  This is usually the
full name of the test method, including the module and class name.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.shortDescription">
<code class="descname">shortDescription</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.shortDescription" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a description of the test, or <code class="docutils literal notranslate"><span class="pre">None</span></code> if no description
has been provided.  The default implementation of this method
returns the first line of the test method’s docstring, if available,
or <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate"><span class="pre">None</span></code></a>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.addCleanup">
<code class="descname">addCleanup</code><span class="sig-paren">(</span><em>function</em>, <em>*args</em>, <em>**kwargs</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.addCleanup" title="Permalink to this definition">¶</a></dt>
<dd><p>Add a function to be called after <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> to cleanup resources
used during the test. Functions will be called in reverse order to the
order they are added (LIFO). They are called with any arguments and
keyword arguments passed into <a class="reference internal" href="#unittest.TestCase.addCleanup" title="unittest.TestCase.addCleanup"><code class="xref py py-meth docutils literal notranslate"><span class="pre">addCleanup()</span></code></a> when they are
added.</p>
<p>If <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> fails, meaning that <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> is not called,
then any cleanup functions added will still be called.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestCase.doCleanups">
<code class="descname">doCleanups</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestCase.doCleanups" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called unconditionally after <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a>, or
after <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> if <a class="reference internal" href="#unittest.TestCase.setUp" title="unittest.TestCase.setUp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setUp()</span></code></a> raises an exception.</p>
<p>It is responsible for calling all the cleanup functions added by
<a class="reference internal" href="#unittest.TestCase.addCleanup" title="unittest.TestCase.addCleanup"><code class="xref py py-meth docutils literal notranslate"><span class="pre">addCleanup()</span></code></a>. If you need cleanup functions to be called
<em>prior</em> to <a class="reference internal" href="#unittest.TestCase.tearDown" title="unittest.TestCase.tearDown"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDown()</span></code></a> then you can call <a class="reference internal" href="#unittest.TestCase.doCleanups" title="unittest.TestCase.doCleanups"><code class="xref py py-meth docutils literal notranslate"><span class="pre">doCleanups()</span></code></a>
yourself.</p>
<p><a class="reference internal" href="#unittest.TestCase.doCleanups" title="unittest.TestCase.doCleanups"><code class="xref py py-meth docutils literal notranslate"><span class="pre">doCleanups()</span></code></a> pops methods off the stack of cleanup
functions one at a time, so it can be called at any time.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

</dd></dl>

<dl class="class">
<dt id="unittest.FunctionTestCase">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">FunctionTestCase</code><span class="sig-paren">(</span><em>testFunc</em>, <em>setUp=None</em>, <em>tearDown=None</em>, <em>description=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.FunctionTestCase" title="Permalink to this definition">¶</a></dt>
<dd><p>This class implements the portion of the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> interface which
allows the test runner to drive the test, but does not provide the methods
which test code can use to check and report errors.  This is used to create
test cases using legacy test code, allowing it to be integrated into a
<a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>-based test framework.</p>
</dd></dl>

<div class="section" id="deprecated-aliases">
<h4>25.3.7.1.1. Deprecated aliases<a class="headerlink" href="#deprecated-aliases" title="Permalink to this headline">¶</a></h4>
<p>For historical reasons, some of the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> methods had one or more
aliases that are now deprecated.  The following table lists the correct names
along with their deprecated aliases:</p>
<blockquote>
<div><table class="docutils align-center">
<colgroup>
<col style="width: 49%" />
<col style="width: 51%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Method Name</p></th>
<th class="head"><p>Deprecated alias(es)</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a></p></td>
<td><p>failUnlessEqual, assertEquals</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotEqual" title="unittest.TestCase.assertNotEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotEqual()</span></code></a></p></td>
<td><p>failIfEqual</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTrue()</span></code></a></p></td>
<td><p>failUnless, assert_</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertFalse" title="unittest.TestCase.assertFalse"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertFalse()</span></code></a></p></td>
<td><p>failIf</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a></p></td>
<td><p>failUnlessRaises</p></td>
</tr>
<tr class="row-odd"><td><p><a class="reference internal" href="#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertAlmostEqual()</span></code></a></p></td>
<td><p>failUnlessAlmostEqual</p></td>
</tr>
<tr class="row-even"><td><p><a class="reference internal" href="#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotAlmostEqual()</span></code></a></p></td>
<td><p>failIfAlmostEqual</p></td>
</tr>
</tbody>
</table>
<div class="deprecated">
<p><span class="versionmodified deprecated">Deprecated since version 2.7: </span>the aliases listed in the second column</p>
</div>
</div></blockquote>
</div>
</div>
<div class="section" id="grouping-tests">
<span id="testsuite-objects"></span><h3>25.3.7.2. Grouping tests<a class="headerlink" href="#grouping-tests" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="unittest.TestSuite">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">TestSuite</code><span class="sig-paren">(</span><em>tests=()</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite" title="Permalink to this definition">¶</a></dt>
<dd><p>This class represents an aggregation of individual test cases and test suites.
The class presents the interface needed by the test runner to allow it to be run
as any other test case.  Running a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> instance is the same as
iterating over the suite, running each test individually.</p>
<p>If <em>tests</em> is given, it must be an iterable of individual test cases or other
test suites that will be used to build the suite initially. Additional methods
are provided to add test cases and suites to the collection later on.</p>
<p><a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> objects behave much like <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> objects, except
they do not actually implement a test.  Instead, they are used to aggregate
tests into groups of tests that should be run together. Some additional
methods are available to add tests to <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> instances:</p>
<dl class="method">
<dt id="unittest.TestSuite.addTest">
<code class="descname">addTest</code><span class="sig-paren">(</span><em>test</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite.addTest" title="Permalink to this definition">¶</a></dt>
<dd><p>Add a <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> or <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> to the suite.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestSuite.addTests">
<code class="descname">addTests</code><span class="sig-paren">(</span><em>tests</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite.addTests" title="Permalink to this definition">¶</a></dt>
<dd><p>Add all the tests from an iterable of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> and <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a>
instances to this test suite.</p>
<p>This is equivalent to iterating over <em>tests</em>, calling <a class="reference internal" href="#unittest.TestSuite.addTest" title="unittest.TestSuite.addTest"><code class="xref py py-meth docutils literal notranslate"><span class="pre">addTest()</span></code></a> for
each element.</p>
</dd></dl>

<p><a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> shares the following methods with <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>:</p>
<dl class="method">
<dt id="unittest.TestSuite.run">
<code class="descname">run</code><span class="sig-paren">(</span><em>result</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite.run" title="Permalink to this definition">¶</a></dt>
<dd><p>Run the tests associated with this suite, collecting the result into the
test result object passed as <em>result</em>.  Note that unlike
<a class="reference internal" href="#unittest.TestCase.run" title="unittest.TestCase.run"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestCase.run()</span></code></a>, <a class="reference internal" href="#unittest.TestSuite.run" title="unittest.TestSuite.run"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestSuite.run()</span></code></a> requires the result object to
be passed in.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestSuite.debug">
<code class="descname">debug</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite.debug" title="Permalink to this definition">¶</a></dt>
<dd><p>Run the tests associated with this suite without collecting the
result. This allows exceptions raised by the test to be propagated to the
caller and can be used to support running tests under a debugger.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestSuite.countTestCases">
<code class="descname">countTestCases</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite.countTestCases" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of tests represented by this test object, including all
individual tests and sub-suites.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestSuite.__iter__">
<code class="descname">__iter__</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestSuite.__iter__" title="Permalink to this definition">¶</a></dt>
<dd><p>Tests grouped by a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> are always accessed by iteration.
Subclasses can lazily provide tests by overriding <a class="reference internal" href="#unittest.TestSuite.__iter__" title="unittest.TestSuite.__iter__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__iter__()</span></code></a>. Note
that this method maybe called several times on a single suite
(for example when counting tests or comparing for equality)
so the tests returned must be the same for repeated iterations.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span>In earlier versions the <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> accessed tests directly rather
than through iteration, so overriding <a class="reference internal" href="#unittest.TestSuite.__iter__" title="unittest.TestSuite.__iter__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__iter__()</span></code></a> wasn’t sufficient
for providing tests.</p>
</div>
</dd></dl>

<p>In the typical usage of a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> object, the <a class="reference internal" href="#unittest.TestSuite.run" title="unittest.TestSuite.run"><code class="xref py py-meth docutils literal notranslate"><span class="pre">run()</span></code></a> method
is invoked by a <code class="xref py py-class docutils literal notranslate"><span class="pre">TestRunner</span></code> rather than by the end-user test harness.</p>
</dd></dl>

</div>
<div class="section" id="loading-and-running-tests">
<h3>25.3.7.3. Loading and running tests<a class="headerlink" href="#loading-and-running-tests" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="unittest.TestLoader">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">TestLoader</code><a class="headerlink" href="#unittest.TestLoader" title="Permalink to this definition">¶</a></dt>
<dd><p>The <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> class is used to create test suites from classes and
modules.  Normally, there is no need to create an instance of this class; the
<a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> module provides an instance that can be shared as
<a class="reference internal" href="#unittest.defaultTestLoader" title="unittest.defaultTestLoader"><code class="xref py py-data docutils literal notranslate"><span class="pre">unittest.defaultTestLoader</span></code></a>.  Using a subclass or instance, however,
allows customization of some configurable properties.</p>
<p><a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> objects have the following methods:</p>
<dl class="method">
<dt id="unittest.TestLoader.loadTestsFromTestCase">
<code class="descname">loadTestsFromTestCase</code><span class="sig-paren">(</span><em>testCaseClass</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestLoader.loadTestsFromTestCase" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a suite of all test cases contained in the <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>-derived
<code class="xref py py-class docutils literal notranslate"><span class="pre">testCaseClass</span></code>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestLoader.loadTestsFromModule">
<code class="descname">loadTestsFromModule</code><span class="sig-paren">(</span><em>module</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestLoader.loadTestsFromModule" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a suite of all test cases contained in the given module. This
method searches <em>module</em> for classes derived from <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> and
creates an instance of the class for each test method defined for the
class.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>While using a hierarchy of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>-derived classes can be
convenient in sharing fixtures and helper functions, defining test
methods on base classes that are not intended to be instantiated
directly does not play well with this method.  Doing so, however, can
be useful when the fixtures are different and defined in subclasses.</p>
</div>
<p>If a module provides a <code class="docutils literal notranslate"><span class="pre">load_tests</span></code> function it will be called to
load the tests. This allows modules to customize test loading.
This is the <a class="reference internal" href="#load-tests-protocol">load_tests protocol</a>.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span>Support for <code class="docutils literal notranslate"><span class="pre">load_tests</span></code> added.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestLoader.loadTestsFromName">
<code class="descname">loadTestsFromName</code><span class="sig-paren">(</span><em>name</em>, <em>module=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestLoader.loadTestsFromName" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a suite of all test cases given a string specifier.</p>
<p>The specifier <em>name</em> is a “dotted name” that may resolve either to a
module, a test case class, a test method within a test case class, a
<a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> instance, or a callable object which returns a
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> or <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> instance.  These checks are
applied in the order listed here; that is, a method on a possible test
case class will be picked up as “a test method within a test case class”,
rather than “a callable object”.</p>
<p>For example, if you have a module <code class="xref py py-mod docutils literal notranslate"><span class="pre">SampleTests</span></code> containing a
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>-derived class <code class="xref py py-class docutils literal notranslate"><span class="pre">SampleTestCase</span></code> with three test
methods (<code class="xref py py-meth docutils literal notranslate"><span class="pre">test_one()</span></code>, <code class="xref py py-meth docutils literal notranslate"><span class="pre">test_two()</span></code>, and <code class="xref py py-meth docutils literal notranslate"><span class="pre">test_three()</span></code>), the
specifier <code class="docutils literal notranslate"><span class="pre">'SampleTests.SampleTestCase'</span></code> would cause this method to
return a suite which will run all three test methods. Using the specifier
<code class="docutils literal notranslate"><span class="pre">'SampleTests.SampleTestCase.test_two'</span></code> would cause it to return a test
suite which will run only the <code class="xref py py-meth docutils literal notranslate"><span class="pre">test_two()</span></code> test method. The specifier
can refer to modules and packages which have not been imported; they will
be imported as a side-effect.</p>
<p>The method optionally resolves <em>name</em> relative to the given <em>module</em>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestLoader.loadTestsFromNames">
<code class="descname">loadTestsFromNames</code><span class="sig-paren">(</span><em>names</em>, <em>module=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestLoader.loadTestsFromNames" title="Permalink to this definition">¶</a></dt>
<dd><p>Similar to <a class="reference internal" href="#unittest.TestLoader.loadTestsFromName" title="unittest.TestLoader.loadTestsFromName"><code class="xref py py-meth docutils literal notranslate"><span class="pre">loadTestsFromName()</span></code></a>, but takes a sequence of names rather
than a single name.  The return value is a test suite which supports all
the tests defined for each name.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestLoader.getTestCaseNames">
<code class="descname">getTestCaseNames</code><span class="sig-paren">(</span><em>testCaseClass</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestLoader.getTestCaseNames" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a sorted sequence of method names found within <em>testCaseClass</em>;
this should be a subclass of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestLoader.discover">
<code class="descname">discover</code><span class="sig-paren">(</span><em>start_dir</em>, <em>pattern='test*.py'</em>, <em>top_level_dir=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestLoader.discover" title="Permalink to this definition">¶</a></dt>
<dd><p>Find all the test modules by recursing into subdirectories from the
specified start directory, and return a TestSuite object containing them.
Only test files that match <em>pattern</em> will be loaded. (Using shell style
pattern matching.) Only module names that are importable (i.e. are valid
Python identifiers) will be loaded.</p>
<p>All test modules must be importable from the top level of the project. If
the start directory is not the top level directory then the top level
directory must be specified separately.</p>
<p>If importing a module fails, for example due to a syntax error, then this
will be recorded as a single error and discovery will continue.</p>
<p>If a test package name (directory with <code class="file docutils literal notranslate"><span class="pre">__init__.py</span></code>) matches the
pattern then the package will be checked for a <code class="docutils literal notranslate"><span class="pre">load_tests</span></code>
function. If this exists then it will be called with <em>loader</em>, <em>tests</em>,
<em>pattern</em>.</p>
<p>If load_tests exists then discovery does <em>not</em> recurse into the package,
<code class="docutils literal notranslate"><span class="pre">load_tests</span></code> is responsible for loading all tests in the package.</p>
<p>The pattern is deliberately not stored as a loader attribute so that
packages can continue discovery themselves. <em>top_level_dir</em> is stored so
<code class="docutils literal notranslate"><span class="pre">load_tests</span></code> does not need to pass this argument in to
<code class="docutils literal notranslate"><span class="pre">loader.discover()</span></code>.</p>
<p><em>start_dir</em> can be a dotted module name as well as a directory.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<p>The following attributes of a <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> can be configured either by
subclassing or assignment on an instance:</p>
<dl class="attribute">
<dt id="unittest.TestLoader.testMethodPrefix">
<code class="descname">testMethodPrefix</code><a class="headerlink" href="#unittest.TestLoader.testMethodPrefix" title="Permalink to this definition">¶</a></dt>
<dd><p>String giving the prefix of method names which will be interpreted as test
methods.  The default value is <code class="docutils literal notranslate"><span class="pre">'test'</span></code>.</p>
<p>This affects <a class="reference internal" href="#unittest.TestLoader.getTestCaseNames" title="unittest.TestLoader.getTestCaseNames"><code class="xref py py-meth docutils literal notranslate"><span class="pre">getTestCaseNames()</span></code></a> and all the <code class="xref py py-meth docutils literal notranslate"><span class="pre">loadTestsFrom*()</span></code>
methods.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestLoader.sortTestMethodsUsing">
<code class="descname">sortTestMethodsUsing</code><a class="headerlink" href="#unittest.TestLoader.sortTestMethodsUsing" title="Permalink to this definition">¶</a></dt>
<dd><p>Function to be used to compare method names when sorting them in
<a class="reference internal" href="#unittest.TestLoader.getTestCaseNames" title="unittest.TestLoader.getTestCaseNames"><code class="xref py py-meth docutils literal notranslate"><span class="pre">getTestCaseNames()</span></code></a> and all the <code class="xref py py-meth docutils literal notranslate"><span class="pre">loadTestsFrom*()</span></code> methods. The
default value is the built-in <a class="reference internal" href="functions.html#cmp" title="cmp"><code class="xref py py-func docutils literal notranslate"><span class="pre">cmp()</span></code></a> function; the attribute can also
be set to <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate"><span class="pre">None</span></code></a> to disable the sort.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestLoader.suiteClass">
<code class="descname">suiteClass</code><a class="headerlink" href="#unittest.TestLoader.suiteClass" title="Permalink to this definition">¶</a></dt>
<dd><p>Callable object that constructs a test suite from a list of tests. No
methods on the resulting object are needed.  The default value is the
<a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> class.</p>
<p>This affects all the <code class="xref py py-meth docutils literal notranslate"><span class="pre">loadTestsFrom*()</span></code> methods.</p>
</dd></dl>

</dd></dl>

<dl class="class">
<dt id="unittest.TestResult">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">TestResult</code><a class="headerlink" href="#unittest.TestResult" title="Permalink to this definition">¶</a></dt>
<dd><p>This class is used to compile information about which tests have succeeded
and which have failed.</p>
<p>A <a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> object stores the results of a set of tests.  The
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> and <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> classes ensure that results are
properly recorded; test authors do not need to worry about recording the
outcome of tests.</p>
<p>Testing frameworks built on top of <a class="reference internal" href="#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> may want access to the
<a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> object generated by running a set of tests for reporting
purposes; a <a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> instance is returned by the
<code class="xref py py-meth docutils literal notranslate"><span class="pre">TestRunner.run()</span></code> method for this purpose.</p>
<p><a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> instances have the following attributes that will be of
interest when inspecting the results of running a set of tests:</p>
<dl class="attribute">
<dt id="unittest.TestResult.errors">
<code class="descname">errors</code><a class="headerlink" href="#unittest.TestResult.errors" title="Permalink to this definition">¶</a></dt>
<dd><p>A list containing 2-tuples of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances and strings
holding formatted tracebacks. Each tuple represents a test which raised an
unexpected exception.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.2: </span>Contains formatted tracebacks instead of <a class="reference internal" href="sys.html#sys.exc_info" title="sys.exc_info"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exc_info()</span></code></a> results.</p>
</div>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.failures">
<code class="descname">failures</code><a class="headerlink" href="#unittest.TestResult.failures" title="Permalink to this definition">¶</a></dt>
<dd><p>A list containing 2-tuples of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances and strings
holding formatted tracebacks. Each tuple represents a test where a failure
was explicitly signalled using the <code class="xref py py-meth docutils literal notranslate"><span class="pre">TestCase.assert*()</span></code> methods.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.2: </span>Contains formatted tracebacks instead of <a class="reference internal" href="sys.html#sys.exc_info" title="sys.exc_info"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exc_info()</span></code></a> results.</p>
</div>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.skipped">
<code class="descname">skipped</code><a class="headerlink" href="#unittest.TestResult.skipped" title="Permalink to this definition">¶</a></dt>
<dd><p>A list containing 2-tuples of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances and strings
holding the reason for skipping the test.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.expectedFailures">
<code class="descname">expectedFailures</code><a class="headerlink" href="#unittest.TestResult.expectedFailures" title="Permalink to this definition">¶</a></dt>
<dd><p>A list containing 2-tuples of <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances and strings
holding formatted tracebacks.  Each tuple represents an expected failure
of the test case.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.unexpectedSuccesses">
<code class="descname">unexpectedSuccesses</code><a class="headerlink" href="#unittest.TestResult.unexpectedSuccesses" title="Permalink to this definition">¶</a></dt>
<dd><p>A list containing <a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> instances that were marked as expected
failures, but succeeded.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.shouldStop">
<code class="descname">shouldStop</code><a class="headerlink" href="#unittest.TestResult.shouldStop" title="Permalink to this definition">¶</a></dt>
<dd><p>Set to <code class="docutils literal notranslate"><span class="pre">True</span></code> when the execution of tests should stop by <a class="reference internal" href="#unittest.TestResult.stop" title="unittest.TestResult.stop"><code class="xref py py-meth docutils literal notranslate"><span class="pre">stop()</span></code></a>.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.testsRun">
<code class="descname">testsRun</code><a class="headerlink" href="#unittest.TestResult.testsRun" title="Permalink to this definition">¶</a></dt>
<dd><p>The total number of tests run so far.</p>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.buffer">
<code class="descname">buffer</code><a class="headerlink" href="#unittest.TestResult.buffer" title="Permalink to this definition">¶</a></dt>
<dd><p>If set to true, <code class="docutils literal notranslate"><span class="pre">sys.stdout</span></code> and <code class="docutils literal notranslate"><span class="pre">sys.stderr</span></code> will be buffered in between
<a class="reference internal" href="#unittest.TestResult.startTest" title="unittest.TestResult.startTest"><code class="xref py py-meth docutils literal notranslate"><span class="pre">startTest()</span></code></a> and <a class="reference internal" href="#unittest.TestResult.stopTest" title="unittest.TestResult.stopTest"><code class="xref py py-meth docutils literal notranslate"><span class="pre">stopTest()</span></code></a> being called. Collected output will
only be echoed onto the real <code class="docutils literal notranslate"><span class="pre">sys.stdout</span></code> and <code class="docutils literal notranslate"><span class="pre">sys.stderr</span></code> if the test
fails or errors. Any output is also attached to the failure / error message.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="attribute">
<dt id="unittest.TestResult.failfast">
<code class="descname">failfast</code><a class="headerlink" href="#unittest.TestResult.failfast" title="Permalink to this definition">¶</a></dt>
<dd><p>If set to true <a class="reference internal" href="#unittest.TestResult.stop" title="unittest.TestResult.stop"><code class="xref py py-meth docutils literal notranslate"><span class="pre">stop()</span></code></a> will be called on the first failure or error,
halting the test run.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.wasSuccessful">
<code class="descname">wasSuccessful</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.wasSuccessful" title="Permalink to this definition">¶</a></dt>
<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if all tests run so far have passed, otherwise returns
<code class="docutils literal notranslate"><span class="pre">False</span></code>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.stop">
<code class="descname">stop</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.stop" title="Permalink to this definition">¶</a></dt>
<dd><p>This method can be called to signal that the set of tests being run should
be aborted by setting the <a class="reference internal" href="#unittest.TestResult.shouldStop" title="unittest.TestResult.shouldStop"><code class="xref py py-attr docutils literal notranslate"><span class="pre">shouldStop</span></code></a> attribute to <code class="docutils literal notranslate"><span class="pre">True</span></code>.
<code class="xref py py-class docutils literal notranslate"><span class="pre">TestRunner</span></code> objects should respect this flag and return without
running any additional tests.</p>
<p>For example, this feature is used by the <a class="reference internal" href="#unittest.TextTestRunner" title="unittest.TextTestRunner"><code class="xref py py-class docutils literal notranslate"><span class="pre">TextTestRunner</span></code></a> class to
stop the test framework when the user signals an interrupt from the
keyboard.  Interactive tools which provide <code class="xref py py-class docutils literal notranslate"><span class="pre">TestRunner</span></code>
implementations can use this in a similar manner.</p>
</dd></dl>

<p>The following methods of the <a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> class are used to maintain
the internal data structures, and may be extended in subclasses to support
additional reporting requirements.  This is particularly useful in building
tools which support interactive reporting while tests are being run.</p>
<dl class="method">
<dt id="unittest.TestResult.startTest">
<code class="descname">startTest</code><span class="sig-paren">(</span><em>test</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.startTest" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> is about to be run.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.stopTest">
<code class="descname">stopTest</code><span class="sig-paren">(</span><em>test</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.stopTest" title="Permalink to this definition">¶</a></dt>
<dd><p>Called after the test case <em>test</em> has been executed, regardless of the
outcome.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.startTestRun">
<code class="descname">startTestRun</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.startTestRun" title="Permalink to this definition">¶</a></dt>
<dd><p>Called once before any tests are executed.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.stopTestRun">
<code class="descname">stopTestRun</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.stopTestRun" title="Permalink to this definition">¶</a></dt>
<dd><p>Called once after all tests are executed.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.addError">
<code class="descname">addError</code><span class="sig-paren">(</span><em>test</em>, <em>err</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.addError" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> raises an unexpected exception. <em>err</em> is a
tuple of the form returned by <a class="reference internal" href="sys.html#sys.exc_info" title="sys.exc_info"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exc_info()</span></code></a>: <code class="docutils literal notranslate"><span class="pre">(type,</span> <span class="pre">value,</span>
<span class="pre">traceback)</span></code>.</p>
<p>The default implementation appends a tuple <code class="docutils literal notranslate"><span class="pre">(test,</span> <span class="pre">formatted_err)</span></code> to
the instance’s <a class="reference internal" href="#unittest.TestResult.errors" title="unittest.TestResult.errors"><code class="xref py py-attr docutils literal notranslate"><span class="pre">errors</span></code></a> attribute, where <em>formatted_err</em> is a
formatted traceback derived from <em>err</em>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.addFailure">
<code class="descname">addFailure</code><span class="sig-paren">(</span><em>test</em>, <em>err</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.addFailure" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> signals a failure. <em>err</em> is a tuple of
the form returned by <a class="reference internal" href="sys.html#sys.exc_info" title="sys.exc_info"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exc_info()</span></code></a>: <code class="docutils literal notranslate"><span class="pre">(type,</span> <span class="pre">value,</span> <span class="pre">traceback)</span></code>.</p>
<p>The default implementation appends a tuple <code class="docutils literal notranslate"><span class="pre">(test,</span> <span class="pre">formatted_err)</span></code> to
the instance’s <a class="reference internal" href="#unittest.TestResult.failures" title="unittest.TestResult.failures"><code class="xref py py-attr docutils literal notranslate"><span class="pre">failures</span></code></a> attribute, where <em>formatted_err</em> is a
formatted traceback derived from <em>err</em>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.addSuccess">
<code class="descname">addSuccess</code><span class="sig-paren">(</span><em>test</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.addSuccess" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> succeeds.</p>
<p>The default implementation does nothing.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.addSkip">
<code class="descname">addSkip</code><span class="sig-paren">(</span><em>test</em>, <em>reason</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.addSkip" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> is skipped.  <em>reason</em> is the reason the
test gave for skipping.</p>
<p>The default implementation appends a tuple <code class="docutils literal notranslate"><span class="pre">(test,</span> <span class="pre">reason)</span></code> to the
instance’s <a class="reference internal" href="#unittest.TestResult.skipped" title="unittest.TestResult.skipped"><code class="xref py py-attr docutils literal notranslate"><span class="pre">skipped</span></code></a> attribute.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.addExpectedFailure">
<code class="descname">addExpectedFailure</code><span class="sig-paren">(</span><em>test</em>, <em>err</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.addExpectedFailure" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> fails, but was marked with the
<a class="reference internal" href="#unittest.expectedFailure" title="unittest.expectedFailure"><code class="xref py py-func docutils literal notranslate"><span class="pre">expectedFailure()</span></code></a> decorator.</p>
<p>The default implementation appends a tuple <code class="docutils literal notranslate"><span class="pre">(test,</span> <span class="pre">formatted_err)</span></code> to
the instance’s <a class="reference internal" href="#unittest.TestResult.expectedFailures" title="unittest.TestResult.expectedFailures"><code class="xref py py-attr docutils literal notranslate"><span class="pre">expectedFailures</span></code></a> attribute, where <em>formatted_err</em>
is a formatted traceback derived from <em>err</em>.</p>
</dd></dl>

<dl class="method">
<dt id="unittest.TestResult.addUnexpectedSuccess">
<code class="descname">addUnexpectedSuccess</code><span class="sig-paren">(</span><em>test</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TestResult.addUnexpectedSuccess" title="Permalink to this definition">¶</a></dt>
<dd><p>Called when the test case <em>test</em> was marked with the
<a class="reference internal" href="#unittest.expectedFailure" title="unittest.expectedFailure"><code class="xref py py-func docutils literal notranslate"><span class="pre">expectedFailure()</span></code></a> decorator, but succeeded.</p>
<p>The default implementation appends the test to the instance’s
<a class="reference internal" href="#unittest.TestResult.unexpectedSuccesses" title="unittest.TestResult.unexpectedSuccesses"><code class="xref py py-attr docutils literal notranslate"><span class="pre">unexpectedSuccesses</span></code></a> attribute.</p>
</dd></dl>

</dd></dl>

<dl class="class">
<dt id="unittest.TextTestResult">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">TextTestResult</code><span class="sig-paren">(</span><em>stream</em>, <em>descriptions</em>, <em>verbosity</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TextTestResult" title="Permalink to this definition">¶</a></dt>
<dd><p>A concrete implementation of <a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> used by the
<a class="reference internal" href="#unittest.TextTestRunner" title="unittest.TextTestRunner"><code class="xref py py-class docutils literal notranslate"><span class="pre">TextTestRunner</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7: </span>This class was previously named <code class="docutils literal notranslate"><span class="pre">_TextTestResult</span></code>. The old name still
exists as an alias but is deprecated.</p>
</div>
</dd></dl>

<dl class="data">
<dt id="unittest.defaultTestLoader">
<code class="descclassname">unittest.</code><code class="descname">defaultTestLoader</code><a class="headerlink" href="#unittest.defaultTestLoader" title="Permalink to this definition">¶</a></dt>
<dd><p>Instance of the <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> class intended to be shared.  If no
customization of the <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> is needed, this instance can be used
instead of repeatedly creating new instances.</p>
</dd></dl>

<dl class="class">
<dt id="unittest.TextTestRunner">
<em class="property">class </em><code class="descclassname">unittest.</code><code class="descname">TextTestRunner</code><span class="sig-paren">(</span><em>stream=sys.stderr</em>, <em>descriptions=True</em>, <em>verbosity=1</em>, <em>failfast=False</em>, <em>buffer=False</em>, <em>resultclass=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TextTestRunner" title="Permalink to this definition">¶</a></dt>
<dd><p>A basic test runner implementation which prints results on standard error. It
has a few configurable parameters, but is essentially very simple.  Graphical
applications which run test suites should provide alternate implementations.</p>
<dl class="method">
<dt id="unittest.TextTestRunner._makeResult">
<code class="descname">_makeResult</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.TextTestRunner._makeResult" title="Permalink to this definition">¶</a></dt>
<dd><p>This method returns the instance of <code class="docutils literal notranslate"><span class="pre">TestResult</span></code> used by <code class="xref py py-meth docutils literal notranslate"><span class="pre">run()</span></code>.
It is not intended to be called directly, but can be overridden in
subclasses to provide a custom <code class="docutils literal notranslate"><span class="pre">TestResult</span></code>.</p>
<p><code class="docutils literal notranslate"><span class="pre">_makeResult()</span></code> instantiates the class or callable passed in the
<code class="docutils literal notranslate"><span class="pre">TextTestRunner</span></code> constructor as the <code class="docutils literal notranslate"><span class="pre">resultclass</span></code> argument. It
defaults to <a class="reference internal" href="#unittest.TextTestResult" title="unittest.TextTestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TextTestResult</span></code></a> if no <code class="docutils literal notranslate"><span class="pre">resultclass</span></code> is provided.
The result class is instantiated with the following arguments:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">stream</span><span class="p">,</span> <span class="n">descriptions</span><span class="p">,</span> <span class="n">verbosity</span>
</pre></div>
</div>
</dd></dl>

</dd></dl>

<dl class="function">
<dt id="unittest.main">
<code class="descclassname">unittest.</code><code class="descname">main</code><span class="sig-paren">(</span><span class="optional">[</span><em>module</em><span class="optional">[</span>, <em>defaultTest</em><span class="optional">[</span>, <em>argv</em><span class="optional">[</span>, <em>testRunner</em><span class="optional">[</span>, <em>testLoader</em><span class="optional">[</span>, <em>exit</em><span class="optional">[</span>, <em>verbosity</em><span class="optional">[</span>, <em>failfast</em><span class="optional">[</span>, <em>catchbreak</em><span class="optional">[</span>, <em>buffer</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.main" title="Permalink to this definition">¶</a></dt>
<dd><p>A command-line program that loads a set of tests from <em>module</em> and runs them;
this is primarily for making test modules conveniently executable.
The simplest use for this function is to include the following line at the
end of a test script:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="vm">__name__</span> <span class="o">==</span> <span class="s1">&#39;__main__&#39;</span><span class="p">:</span>
    <span class="n">unittest</span><span class="o">.</span><span class="n">main</span><span class="p">()</span>
</pre></div>
</div>
<p>You can run tests with more detailed information by passing in the verbosity
argument:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="vm">__name__</span> <span class="o">==</span> <span class="s1">&#39;__main__&#39;</span><span class="p">:</span>
    <span class="n">unittest</span><span class="o">.</span><span class="n">main</span><span class="p">(</span><span class="n">verbosity</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>
</pre></div>
</div>
<p>The <em>defaultTest</em> argument is the name of the test to run if no test names
are specified via <em>argv</em>.  If not specified or <code class="docutils literal notranslate"><span class="pre">None</span></code> and no test names are
provided via <em>argv</em>, all tests found in <em>module</em> are run.</p>
<p>The <em>argv</em> argument can be a list of options passed to the program, with the
first element being the program name.  If not specified or <code class="docutils literal notranslate"><span class="pre">None</span></code>,
the values of <a class="reference internal" href="sys.html#sys.argv" title="sys.argv"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.argv</span></code></a> are used.</p>
<p>The <em>testRunner</em> argument can either be a test runner class or an already
created instance of it. By default <code class="docutils literal notranslate"><span class="pre">main</span></code> calls <a class="reference internal" href="sys.html#sys.exit" title="sys.exit"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exit()</span></code></a> with
an exit code indicating success or failure of the tests run.</p>
<p>The <em>testLoader</em> argument has to be a <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> instance,
and defaults to <a class="reference internal" href="#unittest.defaultTestLoader" title="unittest.defaultTestLoader"><code class="xref py py-data docutils literal notranslate"><span class="pre">defaultTestLoader</span></code></a>.</p>
<p><code class="docutils literal notranslate"><span class="pre">main</span></code> supports being used from the interactive interpreter by passing in the
argument <code class="docutils literal notranslate"><span class="pre">exit=False</span></code>. This displays the result on standard output without
calling <a class="reference internal" href="sys.html#sys.exit" title="sys.exit"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exit()</span></code></a>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">from</span> <span class="nn">unittest</span> <span class="k">import</span> <span class="n">main</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">main</span><span class="p">(</span><span class="n">module</span><span class="o">=</span><span class="s1">&#39;test_module&#39;</span><span class="p">,</span> <span class="n">exit</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span>
</pre></div>
</div>
<p>The <em>failfast</em>, <em>catchbreak</em> and <em>buffer</em> parameters have the same
effect as the same-name <a class="reference internal" href="#command-line-options">command-line options</a>.</p>
<p>Calling <code class="docutils literal notranslate"><span class="pre">main</span></code> actually returns an instance of the <code class="docutils literal notranslate"><span class="pre">TestProgram</span></code> class.
This stores the result of the tests run as the <code class="docutils literal notranslate"><span class="pre">result</span></code> attribute.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 2.7: </span>The <em>exit</em>, <em>verbosity</em>, <em>failfast</em>, <em>catchbreak</em> and <em>buffer</em>
parameters were added.</p>
</div>
</dd></dl>

<div class="section" id="load-tests-protocol">
<h4>25.3.7.3.1. load_tests Protocol<a class="headerlink" href="#load-tests-protocol" title="Permalink to this headline">¶</a></h4>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
<p>Modules or packages can customize how tests are loaded from them during normal
test runs or test discovery by implementing a function called <code class="docutils literal notranslate"><span class="pre">load_tests</span></code>.</p>
<p>If a test module defines <code class="docutils literal notranslate"><span class="pre">load_tests</span></code> it will be called by
<a class="reference internal" href="#unittest.TestLoader.loadTestsFromModule" title="unittest.TestLoader.loadTestsFromModule"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestLoader.loadTestsFromModule()</span></code></a> with the following arguments:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">load_tests</span><span class="p">(</span><span class="n">loader</span><span class="p">,</span> <span class="n">standard_tests</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span>
</pre></div>
</div>
<p>It should return a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a>.</p>
<p><em>loader</em> is the instance of <a class="reference internal" href="#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> doing the loading.
<em>standard_tests</em> are the tests that would be loaded by default from the
module. It is common for test modules to only want to add or remove tests
from the standard set of tests.
The third argument is used when loading packages as part of test discovery.</p>
<p>A typical <code class="docutils literal notranslate"><span class="pre">load_tests</span></code> function that loads tests from a specific set of
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> classes may look like:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">test_cases</span> <span class="o">=</span> <span class="p">(</span><span class="n">TestCase1</span><span class="p">,</span> <span class="n">TestCase2</span><span class="p">,</span> <span class="n">TestCase3</span><span class="p">)</span>

<span class="k">def</span> <span class="nf">load_tests</span><span class="p">(</span><span class="n">loader</span><span class="p">,</span> <span class="n">tests</span><span class="p">,</span> <span class="n">pattern</span><span class="p">):</span>
    <span class="n">suite</span> <span class="o">=</span> <span class="n">TestSuite</span><span class="p">()</span>
    <span class="k">for</span> <span class="n">test_class</span> <span class="ow">in</span> <span class="n">test_cases</span><span class="p">:</span>
        <span class="n">tests</span> <span class="o">=</span> <span class="n">loader</span><span class="o">.</span><span class="n">loadTestsFromTestCase</span><span class="p">(</span><span class="n">test_class</span><span class="p">)</span>
        <span class="n">suite</span><span class="o">.</span><span class="n">addTests</span><span class="p">(</span><span class="n">tests</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">suite</span>
</pre></div>
</div>
<p>If discovery is started, either from the command line or by calling
<a class="reference internal" href="#unittest.TestLoader.discover" title="unittest.TestLoader.discover"><code class="xref py py-meth docutils literal notranslate"><span class="pre">TestLoader.discover()</span></code></a>, with a pattern that matches a package
name then the package <code class="file docutils literal notranslate"><span class="pre">__init__.py</span></code> will be checked for <code class="docutils literal notranslate"><span class="pre">load_tests</span></code>.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>The default pattern is <code class="docutils literal notranslate"><span class="pre">'test*.py'</span></code>. This matches all Python files
that start with <code class="docutils literal notranslate"><span class="pre">'test'</span></code> but <em>won’t</em> match any test directories.</p>
<p>A pattern like <code class="docutils literal notranslate"><span class="pre">'test*'</span></code> will match test packages as well as
modules.</p>
</div>
<p>If the package <code class="file docutils literal notranslate"><span class="pre">__init__.py</span></code> defines <code class="docutils literal notranslate"><span class="pre">load_tests</span></code> then it will be
called and discovery not continued into the package. <code class="docutils literal notranslate"><span class="pre">load_tests</span></code>
is called with the following arguments:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">load_tests</span><span class="p">(</span><span class="n">loader</span><span class="p">,</span> <span class="n">standard_tests</span><span class="p">,</span> <span class="n">pattern</span><span class="p">)</span>
</pre></div>
</div>
<p>This should return a <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a> representing all the tests
from the package. (<code class="docutils literal notranslate"><span class="pre">standard_tests</span></code> will only contain tests
collected from <code class="file docutils literal notranslate"><span class="pre">__init__.py</span></code>.)</p>
<p>Because the pattern is passed into <code class="docutils literal notranslate"><span class="pre">load_tests</span></code> the package is free to
continue (and potentially modify) test discovery. A ‘do nothing’
<code class="docutils literal notranslate"><span class="pre">load_tests</span></code> function for a test package would look like:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">load_tests</span><span class="p">(</span><span class="n">loader</span><span class="p">,</span> <span class="n">standard_tests</span><span class="p">,</span> <span class="n">pattern</span><span class="p">):</span>
    <span class="c1"># top level directory cached on loader instance</span>
    <span class="n">this_dir</span> <span class="o">=</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">dirname</span><span class="p">(</span><span class="vm">__file__</span><span class="p">)</span>
    <span class="n">package_tests</span> <span class="o">=</span> <span class="n">loader</span><span class="o">.</span><span class="n">discover</span><span class="p">(</span><span class="n">start_dir</span><span class="o">=</span><span class="n">this_dir</span><span class="p">,</span> <span class="n">pattern</span><span class="o">=</span><span class="n">pattern</span><span class="p">)</span>
    <span class="n">standard_tests</span><span class="o">.</span><span class="n">addTests</span><span class="p">(</span><span class="n">package_tests</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">standard_tests</span>
</pre></div>
</div>
</div>
</div>
</div>
<div class="section" id="class-and-module-fixtures">
<h2>25.3.8. Class and Module Fixtures<a class="headerlink" href="#class-and-module-fixtures" title="Permalink to this headline">¶</a></h2>
<p>Class and module level fixtures are implemented in <a class="reference internal" href="#unittest.TestSuite" title="unittest.TestSuite"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestSuite</span></code></a>. When
the test suite encounters a test from a new class then <code class="xref py py-meth docutils literal notranslate"><span class="pre">tearDownClass()</span></code>
from the previous class (if there is one) is called, followed by
<code class="xref py py-meth docutils literal notranslate"><span class="pre">setUpClass()</span></code> from the new class.</p>
<p>Similarly if a test is from a different module from the previous test then
<code class="docutils literal notranslate"><span class="pre">tearDownModule</span></code> from the previous module is run, followed by
<code class="docutils literal notranslate"><span class="pre">setUpModule</span></code> from the new module.</p>
<p>After all the tests have run the final <code class="docutils literal notranslate"><span class="pre">tearDownClass</span></code> and
<code class="docutils literal notranslate"><span class="pre">tearDownModule</span></code> are run.</p>
<p>Note that shared fixtures do not play well with [potential] features like test
parallelization and they break test isolation. They should be used with care.</p>
<p>The default ordering of tests created by the unittest test loaders is to group
all tests from the same modules and classes together. This will lead to
<code class="docutils literal notranslate"><span class="pre">setUpClass</span></code> / <code class="docutils literal notranslate"><span class="pre">setUpModule</span></code> (etc) being called exactly once per class and
module. If you randomize the order, so that tests from different modules and
classes are adjacent to each other, then these shared fixture functions may be
called multiple times in a single test run.</p>
<p>Shared fixtures are not intended to work with suites with non-standard
ordering. A <code class="docutils literal notranslate"><span class="pre">BaseTestSuite</span></code> still exists for frameworks that don’t want to
support shared fixtures.</p>
<p>If there are any exceptions raised during one of the shared fixture functions
the test is reported as an error. Because there is no corresponding test
instance an <code class="docutils literal notranslate"><span class="pre">_ErrorHolder</span></code> object (that has the same interface as a
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>) is created to represent the error. If you are just using
the standard unittest test runner then this detail doesn’t matter, but if you
are a framework author it may be relevant.</p>
<div class="section" id="setupclass-and-teardownclass">
<h3>25.3.8.1. setUpClass and tearDownClass<a class="headerlink" href="#setupclass-and-teardownclass" title="Permalink to this headline">¶</a></h3>
<p>These must be implemented as class methods:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">unittest</span>

<span class="k">class</span> <span class="nc">Test</span><span class="p">(</span><span class="n">unittest</span><span class="o">.</span><span class="n">TestCase</span><span class="p">):</span>
    <span class="nd">@classmethod</span>
    <span class="k">def</span> <span class="nf">setUpClass</span><span class="p">(</span><span class="bp">cls</span><span class="p">):</span>
        <span class="bp">cls</span><span class="o">.</span><span class="n">_connection</span> <span class="o">=</span> <span class="n">createExpensiveConnectionObject</span><span class="p">()</span>

    <span class="nd">@classmethod</span>
    <span class="k">def</span> <span class="nf">tearDownClass</span><span class="p">(</span><span class="bp">cls</span><span class="p">):</span>
        <span class="bp">cls</span><span class="o">.</span><span class="n">_connection</span><span class="o">.</span><span class="n">destroy</span><span class="p">()</span>
</pre></div>
</div>
<p>If you want the <code class="docutils literal notranslate"><span class="pre">setUpClass</span></code> and <code class="docutils literal notranslate"><span class="pre">tearDownClass</span></code> on base classes called
then you must call up to them yourself. The implementations in
<a class="reference internal" href="#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> are empty.</p>
<p>If an exception is raised during a <code class="docutils literal notranslate"><span class="pre">setUpClass</span></code> then the tests in the class
are not run and the <code class="docutils literal notranslate"><span class="pre">tearDownClass</span></code> is not run. Skipped classes will not
have <code class="docutils literal notranslate"><span class="pre">setUpClass</span></code> or <code class="docutils literal notranslate"><span class="pre">tearDownClass</span></code> run. If the exception is a
<a class="reference internal" href="#unittest.SkipTest" title="unittest.SkipTest"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SkipTest</span></code></a> exception then the class will be reported as having been skipped
instead of as an error.</p>
</div>
<div class="section" id="setupmodule-and-teardownmodule">
<h3>25.3.8.2. setUpModule and tearDownModule<a class="headerlink" href="#setupmodule-and-teardownmodule" title="Permalink to this headline">¶</a></h3>
<p>These should be implemented as functions:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">setUpModule</span><span class="p">():</span>
    <span class="n">createConnection</span><span class="p">()</span>

<span class="k">def</span> <span class="nf">tearDownModule</span><span class="p">():</span>
    <span class="n">closeConnection</span><span class="p">()</span>
</pre></div>
</div>
<p>If an exception is raised in a <code class="docutils literal notranslate"><span class="pre">setUpModule</span></code> then none of the tests in the
module will be run and the <code class="docutils literal notranslate"><span class="pre">tearDownModule</span></code> will not be run. If the exception is a
<a class="reference internal" href="#unittest.SkipTest" title="unittest.SkipTest"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SkipTest</span></code></a> exception then the module will be reported as having been skipped
instead of as an error.</p>
</div>
</div>
<div class="section" id="signal-handling">
<h2>25.3.9. Signal Handling<a class="headerlink" href="#signal-handling" title="Permalink to this headline">¶</a></h2>
<p>The <a class="reference internal" href="#cmdoption-unittest-c"><code class="xref std std-option docutils literal notranslate"><span class="pre">-c/--catch</span></code></a> command-line option to unittest,
along with the <code class="docutils literal notranslate"><span class="pre">catchbreak</span></code> parameter to <a class="reference internal" href="#unittest.main" title="unittest.main"><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.main()</span></code></a>, provide
more friendly handling of control-C during a test run. With catch break
behavior enabled control-C will allow the currently running test to complete,
and the test run will then end and report all the results so far. A second
control-c will raise a <a class="reference internal" href="exceptions.html#exceptions.KeyboardInterrupt" title="exceptions.KeyboardInterrupt"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyboardInterrupt</span></code></a> in the usual way.</p>
<p>The control-c handling signal handler attempts to remain compatible with code or
tests that install their own <code class="xref py py-const docutils literal notranslate"><span class="pre">signal.SIGINT</span></code> handler. If the <code class="docutils literal notranslate"><span class="pre">unittest</span></code>
handler is called but <em>isn’t</em> the installed <code class="xref py py-const docutils literal notranslate"><span class="pre">signal.SIGINT</span></code> handler,
i.e. it has been replaced by the system under test and delegated to, then it
calls the default handler. This will normally be the expected behavior by code
that replaces an installed handler and delegates to it. For individual tests
that need <code class="docutils literal notranslate"><span class="pre">unittest</span></code> control-c handling disabled the <a class="reference internal" href="#unittest.removeHandler" title="unittest.removeHandler"><code class="xref py py-func docutils literal notranslate"><span class="pre">removeHandler()</span></code></a>
decorator can be used.</p>
<p>There are a few utility functions for framework authors to enable control-c
handling functionality within test frameworks.</p>
<dl class="function">
<dt id="unittest.installHandler">
<code class="descclassname">unittest.</code><code class="descname">installHandler</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#unittest.installHandler" title="Permalink to this definition">¶</a></dt>
<dd><p>Install the control-c handler. When a <code class="xref py py-const docutils literal notranslate"><span class="pre">signal.SIGINT</span></code> is received
(usually in response to the user pressing control-c) all registered results
have <a class="reference internal" href="#unittest.TestResult.stop" title="unittest.TestResult.stop"><code class="xref py py-meth docutils literal notranslate"><span class="pre">stop()</span></code></a> called.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="unittest.registerResult">
<code class="descclassname">unittest.</code><code class="descname">registerResult</code><span class="sig-paren">(</span><em>result</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.registerResult" title="Permalink to this definition">¶</a></dt>
<dd><p>Register a <a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> object for control-c handling. Registering a
result stores a weak reference to it, so it doesn’t prevent the result from
being garbage collected.</p>
<p>Registering a <a class="reference internal" href="#unittest.TestResult" title="unittest.TestResult"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestResult</span></code></a> object has no side-effects if control-c
handling is not enabled, so test frameworks can unconditionally register
all results they create independently of whether or not handling is enabled.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="unittest.removeResult">
<code class="descclassname">unittest.</code><code class="descname">removeResult</code><span class="sig-paren">(</span><em>result</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.removeResult" title="Permalink to this definition">¶</a></dt>
<dd><p>Remove a registered result. Once a result has been removed then
<a class="reference internal" href="#unittest.TestResult.stop" title="unittest.TestResult.stop"><code class="xref py py-meth docutils literal notranslate"><span class="pre">stop()</span></code></a> will no longer be called on that result object in
response to a control-c.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="unittest.removeHandler">
<code class="descclassname">unittest.</code><code class="descname">removeHandler</code><span class="sig-paren">(</span><em>function=None</em><span class="sig-paren">)</span><a class="headerlink" href="#unittest.removeHandler" title="Permalink to this definition">¶</a></dt>
<dd><p>When called without arguments this function removes the control-c handler
if it has been installed. This function can also be used as a test decorator
to temporarily remove the handler while the test is being executed:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="nd">@unittest</span><span class="o">.</span><span class="n">removeHandler</span>
<span class="k">def</span> <span class="nf">test_signal_handling</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
    <span class="o">...</span>
</pre></div>
</div>
<div class="versionadded">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
</dd></dl>

</div>
</div>


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  <ul>
<li><a class="reference internal" href="#">25.3. <code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code> — Unit testing framework</a><ul>
<li><a class="reference internal" href="#basic-example">25.3.1. Basic example</a></li>
<li><a class="reference internal" href="#command-line-interface">25.3.2. Command-Line Interface</a><ul>
<li><a class="reference internal" href="#command-line-options">25.3.2.1. Command-line options</a></li>
</ul>
</li>
<li><a class="reference internal" href="#test-discovery">25.3.3. Test Discovery</a></li>
<li><a class="reference internal" href="#organizing-test-code">25.3.4. Organizing test code</a></li>
<li><a class="reference internal" href="#re-using-old-test-code">25.3.5. Re-using old test code</a></li>
<li><a class="reference internal" href="#skipping-tests-and-expected-failures">25.3.6. Skipping tests and expected failures</a></li>
<li><a class="reference internal" href="#classes-and-functions">25.3.7. Classes and functions</a><ul>
<li><a class="reference internal" href="#test-cases">25.3.7.1. Test cases</a><ul>
<li><a class="reference internal" href="#deprecated-aliases">25.3.7.1.1. Deprecated aliases</a></li>
</ul>
</li>
<li><a class="reference internal" href="#grouping-tests">25.3.7.2. Grouping tests</a></li>
<li><a class="reference internal" href="#loading-and-running-tests">25.3.7.3. Loading and running tests</a><ul>
<li><a class="reference internal" href="#load-tests-protocol">25.3.7.3.1. load_tests Protocol</a></li>
</ul>
</li>
</ul>
</li>
<li><a class="reference internal" href="#class-and-module-fixtures">25.3.8. Class and Module Fixtures</a><ul>
<li><a class="reference internal" href="#setupclass-and-teardownclass">25.3.8.1. setUpClass and tearDownClass</a></li>
<li><a class="reference internal" href="#setupmodule-and-teardownmodule">25.3.8.2. setUpModule and tearDownModule</a></li>
</ul>
</li>
<li><a class="reference internal" href="#signal-handling">25.3.9. Signal Handling</a></li>
</ul>
</li>
</ul>

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