<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Temporary directories and files</title> <link rel="stylesheet" href="_static/sphinxdoc.css" type="text/css" /> <link rel="stylesheet" href="_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '', VERSION: '2.3.4.1', COLLAPSE_INDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </script> <script type="text/javascript" src="_static/jquery.js"></script> <script type="text/javascript" src="_static/underscore.js"></script> <script type="text/javascript" src="_static/doctools.js"></script> <link rel="top" title="None" href="index.html" /> <link rel="up" title="py.test reference documentation" href="apiref.html" /> <link rel="next" title="Marking test functions with attributes" href="mark.html" /> <link rel="prev" title="xdist: pytest distributed testing plugin" href="xdist.html" /> </head> <body> <div class="related"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="mark.html" title="Marking test functions with attributes" accesskey="N">next</a></li> <li class="right" > <a href="xdist.html" title="xdist: pytest distributed testing plugin" accesskey="P">previous</a> |</li> <li><a href="contents.html">pytest-2.3.4.1</a> »</li> <li><a href="apiref.html" accesskey="U">py.test reference documentation</a> »</li> <g:plusone></g:plusone> </ul> </div> <div class="sphinxsidebar"> <div class="sphinxsidebarwrapper"> <div id="searchbox" style="display: none"> <form class="search" action="search.html" method="get"> <input type="text" name="q" size="18" /> <input type="submit" value="Search" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> <script type="text/javascript">$('#searchbox').show(0);</script> <h3>quicklinks</h3> <div style="text-align: left; font-size: 100%; vertical-align: middle;"> <table> <tr> <td> <a href="index.html">home</a> </td><td> <a href="contents.html">TOC/contents</a> </td></tr><tr><td> <a href="getting-started.html">install</a> </td><td> <a href="changelog.html">changelog</a> </td></tr><tr><td> <a href="example/index.html">examples</a> </td><td> <a href="customize.html">customize</a> </td></tr><tr><td> <a href="https://bitbucket.org/hpk42/pytest/issues?status=new&status=open">issues[bb]</a> </td><td> <a href="contact.html">contact</a> </td></tr></table> </div> <h3><a href="contents.html">Table Of Contents</a></h3> <ul> <li><a class="reference internal" href="#">Temporary directories and files</a><ul> <li><a class="reference internal" href="#the-tmpdir-test-function-argument">The ‘tmpdir’ test function argument</a></li> <li><a class="reference internal" href="#the-default-base-temporary-directory">The default base temporary directory</a></li> </ul> </li> </ul> <h4>Previous topic</h4> <p class="topless"><a href="xdist.html" title="previous chapter">xdist: pytest distributed testing plugin</a></p> <h4>Next topic</h4> <p class="topless"><a href="mark.html" title="next chapter">Marking test functions with attributes</a></p> </div> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body"> <div class="section" id="temporary-directories-and-files"> <span id="tmpdir"></span><span id="tmpdir-handling"></span><h1>Temporary directories and files<a class="headerlink" href="#temporary-directories-and-files" title="Permalink to this headline">¶</a></h1> <div class="section" id="the-tmpdir-test-function-argument"> <h2>The ‘tmpdir’ test function argument<a class="headerlink" href="#the-tmpdir-test-function-argument" title="Permalink to this headline">¶</a></h2> <p>You can use the <tt class="docutils literal"><span class="pre">tmpdir</span></tt> function argument which will provide a temporary directory unique to the test invocation, created in the <a class="reference internal" href="#base-temporary-directory">base temporary directory</a>.</p> <p><tt class="docutils literal"><span class="pre">tmpdir</span></tt> is a <a class="reference external" href="http://py.rtfd.org/path.html">py.path.local</a> object which offers <tt class="docutils literal"><span class="pre">os.path</span></tt> methods and more. Here is an example test usage:</p> <div class="highlight-python"><div class="highlight"><pre><span class="c"># content of test_tmpdir.py</span> <span class="kn">import</span> <span class="nn">os</span> <span class="k">def</span> <span class="nf">test_create_file</span><span class="p">(</span><span class="n">tmpdir</span><span class="p">):</span> <span class="n">p</span> <span class="o">=</span> <span class="n">tmpdir</span><span class="o">.</span><span class="n">mkdir</span><span class="p">(</span><span class="s">"sub"</span><span class="p">)</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="s">"hello.txt"</span><span class="p">)</span> <span class="n">p</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">"content"</span><span class="p">)</span> <span class="k">assert</span> <span class="n">p</span><span class="o">.</span><span class="n">read</span><span class="p">()</span> <span class="o">==</span> <span class="s">"content"</span> <span class="k">assert</span> <span class="nb">len</span><span class="p">(</span><span class="n">tmpdir</span><span class="o">.</span><span class="n">listdir</span><span class="p">())</span> <span class="o">==</span> <span class="mi">1</span> <span class="k">assert</span> <span class="mi">0</span> </pre></div> </div> <p>Running this would result in a passed test except for the last <tt class="docutils literal"><span class="pre">assert</span> <span class="pre">0</span></tt> line which we use to look at values:</p> <div class="highlight-python"><pre>$ py.test test_tmpdir.py =========================== test session starts ============================ platform linux2 -- Python 2.7.3 -- pytest-2.3.5 collected 1 items test_tmpdir.py F ================================= FAILURES ================================= _____________________________ test_create_file _____________________________ tmpdir = local('/tmp/pytest-323/test_create_file0') def test_create_file(tmpdir): p = tmpdir.mkdir("sub").join("hello.txt") p.write("content") assert p.read() == "content" assert len(tmpdir.listdir()) == 1 > assert 0 E assert 0 test_tmpdir.py:7: AssertionError ========================= 1 failed in 0.02 seconds =========================</pre> </div> </div> <div class="section" id="the-default-base-temporary-directory"> <span id="base-temporary-directory"></span><h2>The default base temporary directory<a class="headerlink" href="#the-default-base-temporary-directory" title="Permalink to this headline">¶</a></h2> <p>Temporary directories are by default created as sub-directories of the system temporary directory. The base name will be <tt class="docutils literal"><span class="pre">pytest-NUM</span></tt> where <tt class="docutils literal"><span class="pre">NUM</span></tt> will be incremented with each test run. Moreover, entries older than 3 temporary directories will be removed.</p> <p>You can override the default temporary directory setting like this:</p> <div class="highlight-python"><div class="highlight"><pre><span class="n">py</span><span class="o">.</span><span class="n">test</span> <span class="o">--</span><span class="n">basetemp</span><span class="o">=</span><span class="n">mydir</span> </pre></div> </div> <p>When distributing tests on the local machine, <tt class="docutils literal"><span class="pre">py.test</span></tt> takes care to configure a basetemp directory for the sub processes such that all temporary data lands below a single per-test run basetemp directory.</p> </div> </div> </div> </div> </div> <div class="clearer"></div> </div> <div class="related"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="mark.html" title="Marking test functions with attributes" >next</a></li> <li class="right" > <a href="xdist.html" title="xdist: pytest distributed testing plugin" >previous</a> |</li> <li><a href="contents.html">pytest-2.3.4.1</a> »</li> <li><a href="apiref.html" >py.test reference documentation</a> »</li> <g:plusone></g:plusone> </ul> </div> <div class="footer"> © Copyright 2012, holger krekel. 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