1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Fixture models</title> 5<link rel="stylesheet" href="../../../boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../index.html" title="Boost.Test"> 8<link rel="up" href="../fixtures.html" title="Fixtures"> 9<link rel="prev" href="../fixtures.html" title="Fixtures"> 10<link rel="next" href="case.html" title="Test case fixture"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="../fixtures.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../fixtures.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="case.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h4 class="title"> 27<a name="boost_test.tests_organization.fixtures.models"></a><a class="link" href="models.html" title="Fixture models">Fixture 28 models</a> 29</h4></div></div></div> 30<p> 31 Several fixture interfaces are supported by the <span class="emphasis"><em>Unit Test Framework</em></span>. 32 The choice of the interface depends mainly on the usage of the fixture. 33 </p> 34<h4> 35<a name="boost_test.tests_organization.fixtures.models.h0"></a> 36 <span class="phrase"><a name="boost_test.tests_organization.fixtures.models.fixture_class_model"></a></span><a class="link" href="models.html#boost_test.tests_organization.fixtures.models.fixture_class_model">Fixture 37 class model</a> 38 </h4> 39<p> 40 The <span class="emphasis"><em>Unit Test Framework</em></span> defines the generic fixture 41 class model as follows: 42 </p> 43<pre class="programlisting"><span class="keyword">struct</span> <span class="special"><</span><span class="identifier">fixture</span><span class="special">-</span><span class="identifier">name</span><span class="special">>{</span> 44 <span class="special"><</span><span class="identifier">fixture</span><span class="special">-</span><span class="identifier">name</span><span class="special">>();</span> <span class="comment">// setup function</span> 45 <span class="special">~<</span><span class="identifier">fixture</span><span class="special">-</span><span class="identifier">name</span><span class="special">>();</span> <span class="comment">// teardown function</span> 46<span class="special">};</span> 47</pre> 48<p> 49 In other words a fixture is expected to be implemented as a class where 50 the class constructor serves as a <code class="computeroutput"><span class="identifier">setup</span></code> 51 method and class destructor serves as <code class="computeroutput"><span class="identifier">teardown</span></code> 52 method. 53 </p> 54<p> 55 The class model above has some limitations though: 56 </p> 57<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 58<li class="listitem"> 59 it is not possible to have exceptions in the teardown function, especially 60 any test assertions that aborts the current test case is not possible 61 (as those use exceptions) 62 </li> 63<li class="listitem"> 64 it is sometimes more natural to use the constructor/destructor to perform 65 the necessary resource allocation/release of the fixture, and that 66 will be consumed in the test cases, and check for the proper state 67 of the fixture in separate functions. Those checks are the pre-conditions 68 for the test case to run, and the post-conditions that should be met 69 after the test case has been running. 70 </li> 71</ul></div> 72<p> 73 This is why the <span class="emphasis"><em>Unit Test Framework</em></span> also supports 74 (Boost 1.65 on) optional <code class="computeroutput"><span class="identifier">setup</span></code> 75 and/or <code class="computeroutput"><span class="identifier">teardown</span></code> functions 76 as follow: 77 </p> 78<pre class="programlisting"><span class="keyword">struct</span> <span class="special"><</span><span class="identifier">fixture</span><span class="special">-</span><span class="identifier">name</span><span class="special">>{</span> 79 <span class="special"><</span><span class="identifier">fixture</span><span class="special">-</span><span class="identifier">name</span><span class="special">>();</span> <span class="comment">// ctor</span> 80 <span class="special">~<</span><span class="identifier">fixture</span><span class="special">-</span><span class="identifier">name</span><span class="special">>();</span> <span class="comment">// dtor</span> 81 <span class="keyword">void</span> <span class="identifier">setup</span><span class="special">();</span> <span class="comment">// setup, optional</span> 82 <span class="keyword">void</span> <span class="identifier">teardown</span><span class="special">();</span> <span class="comment">// teardown, optional</span> 83<span class="special">};</span> 84</pre> 85<div class="note"><table border="0" summary="Note"> 86<tr> 87<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../../../../doc/src/images/note.png"></td> 88<th align="left">Note</th> 89</tr> 90<tr><td align="left" valign="top"><p> 91 As mentioned, the declaration/implementation of the <code class="computeroutput"><span class="identifier">setup</span></code> 92 and <code class="computeroutput"><span class="identifier">teardown</span></code> are optional: 93 the <span class="emphasis"><em>Unit Test Framework</em></span> will check the existence 94 of those and will call them adequately. However in C++98, it is not possible 95 to detect those declaration in case those are inherited (it works fine 96 for compiler supporting <code class="computeroutput"><span class="keyword">auto</span></code> 97 and <code class="computeroutput"><span class="keyword">decltype</span></code>). 98 </p></td></tr> 99</table></div> 100<p> 101 This model is expected from fixtures used with <a class="link" href="../../utf_reference/test_org_reference/test_org_boost_test_case_fixture.html" title="BOOST_FIXTURE_TEST_CASE"><code class="computeroutput"><span class="identifier">BOOST_FIXTURE_TEST_CASE</span></code></a> and <a class="link" href="../../utf_reference/test_org_reference/test_org_boost_test_suite_fixture.html" title="BOOST_FIXTURE_TEST_SUITE"><code class="computeroutput"><span class="identifier">BOOST_FIXTURE_TEST_SUITE</span></code></a>. 102 </p> 103<h4> 104<a name="boost_test.tests_organization.fixtures.models.h1"></a> 105 <span class="phrase"><a name="boost_test.tests_organization.fixtures.models.flexible_models"></a></span><a class="link" href="models.html#boost_test.tests_organization.fixtures.models.flexible_models">Flexible 106 models</a> 107 </h4> 108<p> 109 In addition to <a class="link" href="../../utf_reference/test_org_reference/test_org_boost_test_case_fixture.html" title="BOOST_FIXTURE_TEST_CASE"><code class="computeroutput"><span class="identifier">BOOST_FIXTURE_TEST_CASE</span></code></a> and <a class="link" href="../../utf_reference/test_org_reference/test_org_boost_test_suite_fixture.html" title="BOOST_FIXTURE_TEST_SUITE"><code class="computeroutput"><span class="identifier">BOOST_FIXTURE_TEST_SUITE</span></code></a> the 110 <span class="emphasis"><em>Unit Test Framework</em></span> allows to associate fixture with 111 test unit using the decorator <a class="link" href="../../utf_reference/test_org_reference/decorator_fixture.html" title="fixture (decorator)"><code class="computeroutput"><span class="identifier">fixture</span></code></a>. This decorator supports 112 additional models for declaring the <code class="computeroutput"><span class="identifier">setup</span></code> 113 and <code class="computeroutput"><span class="identifier">teardown</span></code>: 114 </p> 115<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 116<li class="listitem"> 117 a fixture defined according to the fixture class model above 118 </li> 119<li class="listitem"> 120<p class="simpara"> 121 a fixture defined according to the extended fixture class model, which 122 allows for the fixture constructor to takes one argument. For example: 123 </p> 124<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">Fx</span> 125<span class="special">{</span> 126 <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span> 127 <span class="identifier">Fx</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s_</span> <span class="special">=</span> <span class="string">""</span><span class="special">)</span> <span class="special">:</span> <span class="identifier">s</span><span class="special">(</span><span class="identifier">s_</span><span class="special">)</span> 128 <span class="special">{</span> <span class="identifier">BOOST_TEST_MESSAGE</span><span class="special">(</span><span class="string">"ctor "</span> <span class="special"><<</span> <span class="identifier">s</span><span class="special">);</span> <span class="special">}</span> 129 <span class="keyword">void</span> <span class="identifier">setup</span><span class="special">()</span> 130 <span class="special">{</span> <span class="identifier">BOOST_TEST_MESSAGE</span><span class="special">(</span><span class="string">"optional setup "</span> <span class="special"><<</span> <span class="identifier">s</span><span class="special">);</span> <span class="special">}</span> 131 <span class="keyword">void</span> <span class="identifier">teardown</span><span class="special">()</span> 132 <span class="special">{</span> <span class="identifier">BOOST_TEST_MESSAGE</span><span class="special">(</span><span class="string">"optional teardown "</span> <span class="special"><<</span> <span class="identifier">s</span><span class="special">);</span> <span class="special">}</span> 133 <span class="special">~</span><span class="identifier">Fx</span><span class="special">()</span> 134 <span class="special">{</span> <span class="identifier">BOOST_TEST_MESSAGE</span><span class="special">(</span><span class="string">"dtor "</span> <span class="special"><<</span> <span class="identifier">s</span><span class="special">);</span> <span class="special">}</span> 135<span class="special">};</span> 136</pre> 137</li> 138<li class="listitem"> 139<p class="simpara"> 140 a fixture defined as a pair of free functions for the <code class="computeroutput"><span class="identifier">setup</span></code> and <code class="computeroutput"><span class="identifier">teardown</span></code> 141 (latter optional) 142 </p> 143<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">setup</span><span class="special">()</span> <span class="special">{</span> <span class="identifier">BOOST_TEST_MESSAGE</span><span class="special">(</span><span class="string">"set up"</span><span class="special">);</span> <span class="special">}</span> 144<span class="keyword">void</span> <span class="identifier">teardown</span><span class="special">()</span> <span class="special">{</span> <span class="identifier">BOOST_TEST_MESSAGE</span><span class="special">(</span><span class="string">"tear down"</span><span class="special">);</span> <span class="special">}</span> 145</pre> 146</li> 147</ul></div> 148<p> 149 For complete example of test module which uses these models please check 150 decorator <a class="link" href="../../utf_reference/test_org_reference/decorator_fixture.html" title="fixture (decorator)"><code class="computeroutput"><span class="identifier">fixture</span></code></a>. 151 </p> 152</div> 153<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 154<td align="left"></td> 155<td align="right"><div class="copyright-footer">Copyright © 2001-2020 Boost.Test contributors<p> 156 Distributed under the Boost Software License, Version 1.0. (See accompanying 157 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 158 </p> 159</div></td> 160</tr></table> 161<hr> 162<div class="spirit-nav"> 163<a accesskey="p" href="../fixtures.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../fixtures.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="case.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 164</div> 165</body> 166</html> 167
