python/mock-1.0.0/html/mocksignature.html
author Carsten "Tomcat" Book <cbook@mozilla.com>
Tue, 30 Jun 2015 10:30:51 +0200
changeset 274663 79800010be78122db7c36d4b5833814fdbf28495
parent 112588 5981ff9d3f45de802d956b2f8e064f49b74cb7a6
permissions -rw-r--r--
Backed out changeset f41a2121425f (bug 1171931) for bustage


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  <div class="section" id="mocksignature">
<h1>mocksignature<a class="headerlink" href="#mocksignature" title="Permalink to this headline"></a></h1>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last"><a class="reference internal" href="helpers.html#auto-speccing"><em>Autospeccing</em></a>, added in mock 0.8, is a more advanced version of
<cite>mocksignature</cite> and can be used for many of the same use cases.</p>
</div>
<p>A problem with using mock objects to replace real objects in your tests is that
<a class="reference internal" href="mock.html#mock.Mock" title="mock.Mock"><tt class="xref py py-class docutils literal"><span class="pre">Mock</span></tt></a> can be <em>too</em> flexible. Your code can treat the mock objects in
any way and you have to manually check that they were called correctly. If your
code calls functions or methods with the wrong number of arguments then mocks
don&#8217;t complain.</p>
<p>The solution to this is <cite>mocksignature</cite>, which creates functions with the
same signature as the original, but delegating to a mock. You can interrogate
the mock in the usual way to check it has been called with the <em>right</em>
arguments, but if it is called with the wrong number of arguments it will
raise a <cite>TypeError</cite> in the same way your production code would.</p>
<p>Another advantage is that your mocked objects are real functions, which can
be useful when your code uses
<a class="reference external" href="http://docs.python.org/library/inspect.html">inspect</a> or depends on
functions being function objects.</p>
<dl class="function">
<dt id="mock.mocksignature">
<tt class="descname">mocksignature</tt><big>(</big><em>func</em>, <em>mock=None</em>, <em>skipfirst=False</em><big>)</big><a class="headerlink" href="#mock.mocksignature" title="Permalink to this definition"></a></dt>
<dd><p>Create a new function with the same signature as <cite>func</cite> that delegates
to <cite>mock</cite>. If <cite>skipfirst</cite> is True the first argument is skipped, useful
for methods where <cite>self</cite> needs to be omitted from the new function.</p>
<p>If you don&#8217;t pass in a <cite>mock</cite> then one will be created for you.</p>
<p>Functions returned by <cite>mocksignature</cite> have many of the same attributes
and assert methods as a mock object.</p>
<p>The mock is set as the <cite>mock</cite> attribute of the returned function for easy
access.</p>
<p><cite>mocksignature</cite> can also be used with classes. It copies the signature of
the <cite>__init__</cite> method.</p>
<p>When used with callable objects (instances) it copies the signature of the
<cite>__call__</cite> method.</p>
</dd></dl>

<p><cite>mocksignature</cite> will work out if it is mocking the signature of a method on
an instance or a method on a class and do the &#8220;right thing&#8221; with the <cite>self</cite>
argument in both cases.</p>
<p>Because of a limitation in the way that arguments are collected by functions
created by <cite>mocksignature</cite> they are <em>always</em> passed as positional arguments
(including defaults) and not keyword arguments.</p>
<div class="section" id="mocksignature-api">
<h2>mocksignature api<a class="headerlink" href="#mocksignature-api" title="Permalink to this headline"></a></h2>
<p>Although the objects returned by <cite>mocksignature</cite> api are real function objects,
they have much of the same api as the <a class="reference internal" href="mock.html#mock.Mock" title="mock.Mock"><tt class="xref py py-class docutils literal"><span class="pre">Mock</span></tt></a> class. This includes the
assert methods:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">def</span> <span class="nf">func</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">,</span> <span class="n">c</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">func</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">called</span>
<span class="go">False</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">return_value</span> <span class="o">=</span> <span class="mi">3</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
<span class="go">3</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">called</span>
<span class="go">True</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">assert_called_once_with</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">4</span><span class="p">)</span>
<span class="gt">Traceback (most recent call last):</span>
  <span class="c">...</span>
<span class="gr">AssertionError: Expected call</span>: <span class="n">mock(1, 2, 4)</span>
<span class="go">Actual call: mock(1, 2, 3)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">call_count</span>
<span class="go">1</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">side_effect</span> <span class="o">=</span> <span class="ne">IndexError</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="p">(</span><span class="mi">4</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">6</span><span class="p">)</span>
<span class="gt">Traceback (most recent call last):</span>
  <span class="c">...</span>
<span class="gr">IndexError</span>
</pre></div>
</div>
<p>The mock object that is being delegated to is available as the <cite>mock</cite> attribute
of the function created by <cite>mocksignature</cite>.</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">func2</span><span class="o">.</span><span class="n">mock</span><span class="o">.</span><span class="n">mock_calls</span>
<span class="go">[call(1, 2, 3), call(4, 5, 6)]</span>
</pre></div>
</div>
<p>The methods and attributes available on functions returned by <cite>mocksignature</cite>
are:</p>
<blockquote>
<div><a class="reference internal" href="mock.html#mock.Mock.assert_any_call" title="mock.Mock.assert_any_call"><tt class="xref py py-meth docutils literal"><span class="pre">assert_any_call()</span></tt></a>, <a class="reference internal" href="mock.html#mock.Mock.assert_called_once_with" title="mock.Mock.assert_called_once_with"><tt class="xref py py-meth docutils literal"><span class="pre">assert_called_once_with()</span></tt></a>,
<a class="reference internal" href="mock.html#mock.Mock.assert_called_with" title="mock.Mock.assert_called_with"><tt class="xref py py-meth docutils literal"><span class="pre">assert_called_with()</span></tt></a>, <a class="reference internal" href="mock.html#mock.Mock.assert_has_calls" title="mock.Mock.assert_has_calls"><tt class="xref py py-meth docutils literal"><span class="pre">assert_has_calls()</span></tt></a>,
<a class="reference internal" href="mock.html#mock.Mock.call_args" title="mock.Mock.call_args"><tt class="xref py py-attr docutils literal"><span class="pre">call_args</span></tt></a>, <a class="reference internal" href="mock.html#mock.Mock.call_args_list" title="mock.Mock.call_args_list"><tt class="xref py py-attr docutils literal"><span class="pre">call_args_list</span></tt></a>,
<a class="reference internal" href="mock.html#mock.Mock.call_count" title="mock.Mock.call_count"><tt class="xref py py-attr docutils literal"><span class="pre">call_count</span></tt></a>, <a class="reference internal" href="mock.html#mock.Mock.called" title="mock.Mock.called"><tt class="xref py py-attr docutils literal"><span class="pre">called</span></tt></a>,
<a class="reference internal" href="mock.html#mock.Mock.method_calls" title="mock.Mock.method_calls"><tt class="xref py py-attr docutils literal"><span class="pre">method_calls</span></tt></a>, <cite>mock</cite>, <a class="reference internal" href="mock.html#mock.Mock.mock_calls" title="mock.Mock.mock_calls"><tt class="xref py py-attr docutils literal"><span class="pre">mock_calls</span></tt></a>,
<a class="reference internal" href="mock.html#mock.Mock.reset_mock" title="mock.Mock.reset_mock"><tt class="xref py py-meth docutils literal"><span class="pre">reset_mock()</span></tt></a>, <a class="reference internal" href="mock.html#mock.Mock.return_value" title="mock.Mock.return_value"><tt class="xref py py-attr docutils literal"><span class="pre">return_value</span></tt></a>, and
<a class="reference internal" href="mock.html#mock.Mock.side_effect" title="mock.Mock.side_effect"><tt class="xref py py-attr docutils literal"><span class="pre">side_effect</span></tt></a>.</div></blockquote>
</div>
<div class="section" id="example-use">
<h2>Example use<a class="headerlink" href="#example-use" title="Permalink to this headline"></a></h2>
<div class="section" id="basic-use">
<h3>Basic use<a class="headerlink" href="#basic-use" title="Permalink to this headline"></a></h3>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">def</span> <span class="nf">function</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">,</span> <span class="n">c</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">mock</span> <span class="o">=</span> <span class="n">Mock</span><span class="p">()</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">function</span><span class="p">,</span> <span class="n">mock</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="p">()</span>
<span class="gt">Traceback (most recent call last):</span>
  <span class="c">...</span>
<span class="gr">TypeError</span>: <span class="n">&lt;lambda&gt;() takes at least 2 arguments (0 given)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="o">.</span><span class="n">return_value</span> <span class="o">=</span> <span class="s">&#39;some value&#39;</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="s">&#39;foo&#39;</span><span class="p">)</span>
<span class="go">&#39;some value&#39;</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="s">&#39;foo&#39;</span><span class="p">)</span>
</pre></div>
</div>
</div>
<div class="section" id="keyword-arguments">
<h3>Keyword arguments<a class="headerlink" href="#keyword-arguments" title="Permalink to this headline"></a></h3>
<p>Note that arguments to functions created by <cite>mocksignature</cite> are always passed
in to the underlying mock by position even when called with keywords:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">def</span> <span class="nf">function</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">,</span> <span class="n">c</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">function</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="o">.</span><span class="n">return_value</span> <span class="o">=</span> <span class="bp">None</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">function</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="bp">None</span><span class="p">)</span>
</pre></div>
</div>
</div>
<div class="section" id="mocking-methods-and-self">
<h3>Mocking methods and self<a class="headerlink" href="#mocking-methods-and-self" title="Permalink to this headline"></a></h3>
<p>When you use <cite>mocksignature</cite> to replace a method on a class then <cite>self</cite>
will be included in the method signature - and you will need to include
the instance when you do your asserts.</p>
<p>As a curious factor of the way Python (2) wraps methods fetched from a class,
we can <em>get</em> the <cite>return_value</cite> from a function set on a class, but we can&#8217;t
set it. We have to do this through the exposed <cite>mock</cite> attribute instead:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">class</span> <span class="nc">SomeClass</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">def</span> <span class="nf">method</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">,</span> <span class="n">c</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
<span class="gp">... </span>        <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">SomeClass</span><span class="o">.</span><span class="n">method</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">SomeClass</span><span class="o">.</span><span class="n">method</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">SomeClass</span><span class="o">.</span><span class="n">method</span><span class="o">.</span><span class="n">mock</span><span class="o">.</span><span class="n">return_value</span> <span class="o">=</span> <span class="bp">None</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span> <span class="o">=</span> <span class="n">SomeClass</span><span class="p">()</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="p">()</span>
<span class="gt">Traceback (most recent call last):</span>
  <span class="c">...</span>
<span class="gr">TypeError</span>: <span class="n">&lt;lambda&gt;() takes at least 4 arguments (1 given)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
</pre></div>
</div>
<p>When you use <cite>mocksignature</cite> on instance methods <cite>self</cite> isn&#8217;t included (and we
can set the <cite>return_value</cite> etc directly):</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">class</span> <span class="nc">SomeClass</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">def</span> <span class="nf">method</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">,</span> <span class="n">c</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
<span class="gp">... </span>        <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span> <span class="o">=</span> <span class="n">SomeClass</span><span class="p">()</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="o">.</span><span class="n">return_value</span> <span class="o">=</span> <span class="bp">None</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
</pre></div>
</div>
</div>
<div class="section" id="mocksignature-with-classes">
<h3>mocksignature with classes<a class="headerlink" href="#mocksignature-with-classes" title="Permalink to this headline"></a></h3>
<p>When used with a class <cite>mocksignature</cite> copies the signature of the <cite>__init__</cite>
method.</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">class</span> <span class="nc">Something</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">foo</span><span class="p">,</span> <span class="n">bar</span><span class="p">):</span>
<span class="gp">... </span>        <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">MockSomething</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">Something</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">instance</span> <span class="o">=</span> <span class="n">MockSomething</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">9</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="k">assert</span> <span class="n">instance</span> <span class="ow">is</span> <span class="n">MockSomething</span><span class="o">.</span><span class="n">return_value</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">MockSomething</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">9</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">MockSomething</span><span class="p">()</span>
<span class="gt">Traceback (most recent call last):</span>
  <span class="c">...</span>
<span class="gr">TypeError</span>: <span class="n">&lt;lambda&gt;() takes at least 2 arguments (0 given)</span>
</pre></div>
</div>
<p>Because the object returned by <cite>mocksignature</cite> is a function rather than a
<cite>Mock</cite> you lose the other capabilities of <cite>Mock</cite>, like dynamic attribute
creation.</p>
</div>
<div class="section" id="mocksignature-with-callable-objects">
<h3>mocksignature with callable objects<a class="headerlink" href="#mocksignature-with-callable-objects" title="Permalink to this headline"></a></h3>
<p>When used with a callable object <cite>mocksignature</cite> copies the signature of the
<cite>__call__</cite> method.</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">class</span> <span class="nc">Something</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">def</span> <span class="nf">__call__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">spam</span><span class="p">,</span> <span class="n">eggs</span><span class="p">):</span>
<span class="gp">... </span>        <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">something</span> <span class="o">=</span> <span class="n">Something</span><span class="p">()</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">mock_something</span> <span class="o">=</span> <span class="n">mocksignature</span><span class="p">(</span><span class="n">something</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">result</span> <span class="o">=</span> <span class="n">mock_something</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">9</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">mock_something</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">9</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">mock_something</span><span class="p">()</span>
<span class="gt">Traceback (most recent call last):</span>
  <span class="c">...</span>
<span class="gr">TypeError</span>: <span class="n">&lt;lambda&gt;() takes at least 2 arguments (0 given)</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="mocksignature-argument-to-patch">
<h2>mocksignature argument to patch<a class="headerlink" href="#mocksignature-argument-to-patch" title="Permalink to this headline"></a></h2>
<p><cite>mocksignature</cite> is available as a keyword argument to <a class="reference internal" href="patch.html#mock.patch" title="mock.patch"><tt class="xref py py-func docutils literal"><span class="pre">patch()</span></tt></a> or
<a class="reference internal" href="patch.html#mock.patch.object" title="mock.patch.object"><tt class="xref py py-func docutils literal"><span class="pre">patch.object()</span></tt></a>. It can be used with functions / methods / classes and
callable objects.</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">class</span> <span class="nc">SomeClass</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="gp">... </span>    <span class="k">def</span> <span class="nf">method</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">,</span> <span class="n">c</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
<span class="gp">... </span>        <span class="k">pass</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="nd">@patch.object</span><span class="p">(</span><span class="n">SomeClass</span><span class="p">,</span> <span class="s">&#39;method&#39;</span><span class="p">,</span> <span class="n">mocksignature</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="gp">... </span><span class="k">def</span> <span class="nf">test</span><span class="p">(</span><span class="n">mock_method</span><span class="p">):</span>
<span class="gp">... </span>    <span class="n">instance</span> <span class="o">=</span> <span class="n">SomeClass</span><span class="p">()</span>
<span class="gp">... </span>    <span class="n">mock_method</span><span class="o">.</span><span class="n">return_value</span> <span class="o">=</span> <span class="bp">None</span>
<span class="gp">... </span>    <span class="n">instance</span><span class="o">.</span><span class="n">method</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
<span class="gp">... </span>    <span class="n">mock_method</span><span class="o">.</span><span class="n">assert_called_with</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="bp">None</span><span class="p">)</span>
<span class="gp">...</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">test</span><span class="p">()</span>
</pre></div>
</div>
</div>
</div>


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  <h3><a href="index.html">Table Of Contents</a></h3>
  <ul>
<li><a class="reference internal" href="#">mocksignature</a><ul>
<li><a class="reference internal" href="#mocksignature-api">mocksignature api</a></li>
<li><a class="reference internal" href="#example-use">Example use</a><ul>
<li><a class="reference internal" href="#basic-use">Basic use</a></li>
<li><a class="reference internal" href="#keyword-arguments">Keyword arguments</a></li>
<li><a class="reference internal" href="#mocking-methods-and-self">Mocking methods and self</a></li>
<li><a class="reference internal" href="#mocksignature-with-classes">mocksignature with classes</a></li>
<li><a class="reference internal" href="#mocksignature-with-callable-objects">mocksignature with callable objects</a></li>
</ul>
</li>
<li><a class="reference internal" href="#mocksignature-argument-to-patch">mocksignature argument to patch</a></li>
</ul>
</li>
</ul>

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