1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>random</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="../rt_param_reference.html" title="Runtime parameters reference"> 9<link rel="prev" href="output_format.html" title="output_format"> 10<link rel="next" href="report_format.html" title="report_format"> 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="output_format.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../rt_param_reference.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="report_format.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.utf_reference.rt_param_reference.random"></a><a class="link" href="random.html" title="random"><code class="computeroutput"><span class="identifier">random</span></code></a> 28</h4></div></div></div> 29<p> 30 Parameter <span class="emphasis"><em>random</em></span> instructs the <span class="emphasis"><em>Unit Test 31 Framework</em></span> to execute the test cases in random order. This parameter 32 accepts an optional <code class="computeroutput"><span class="keyword">unsigned</span> <span class="identifier">integer</span></code> argument for the seed of the 33 random generator: 34 </p> 35<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 36<li class="listitem"> 37 By default (value <code class="computeroutput"><span class="number">0</span></code>), the 38 test cases are executed in some specific order defined by the order 39 of test units in the test files, and the dependencies between test 40 units. 41 </li> 42<li class="listitem"> 43 If the parameter is specified without the argument value, or with value 44 <code class="computeroutput"><span class="number">1</span></code>, the testing order is 45 randomized based on current time. 46 </li> 47<li class="listitem"> 48 Alternatively, any positive value greater than <code class="computeroutput"><span class="number">1</span></code> 49 will be used as random seed for the run. 50 </li> 51</ul></div> 52<div class="tip"><table border="0" summary="Tip"> 53<tr> 54<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../../../doc/src/images/tip.png"></td> 55<th align="left">Tip</th> 56</tr> 57<tr><td align="left" valign="top"><p> 58 in case <code class="computeroutput"><span class="special">--</span><span class="identifier">random</span></code> 59 is specified, the value of the seed is logged using <a class="link" href="../testout_reference/test_output_macro_message.html" title="BOOST_TEST_MESSAGE"><code class="computeroutput"><span class="identifier">BOOST_TEST_MESSAGE</span></code></a>, so that 60 it is possible to replay exactly the same sequence of unit test in case 61 of failure. For the seed to be visible in the logs, make sure the proper 62 <a class="link" href="log_level.html" title="log_level"><code class="computeroutput"><span class="special">--</span><span class="identifier">log_level</span></code></a> 63 is set. 64 </p></td></tr> 65</table></div> 66<h5> 67<a name="boost_test.utf_reference.rt_param_reference.random.h0"></a> 68 <span class="phrase"><a name="boost_test.utf_reference.rt_param_reference.random.acceptable_values"></a></span><a class="link" href="random.html#boost_test.utf_reference.rt_param_reference.random.acceptable_values">Acceptable 69 values</a> 70 </h5> 71<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 72<li class="listitem"> 73 <span class="bold"><strong>0</strong></span> (default): no randomization 74 </li> 75<li class="listitem"> 76 <code class="computeroutput"><span class="number">1</span></code>: random seed based on 77 the current time 78 </li> 79<li class="listitem"> 80 <a class="link" href="../rt_param_reference.html#regular_param_value">integer</a> <code class="computeroutput"><span class="identifier">value</span> 81 <span class="special">></span> <span class="number">1</span></code> 82 : seed for the random number generator 83 </li> 84</ul></div> 85<h5> 86<a name="boost_test.utf_reference.rt_param_reference.random.h1"></a> 87 <span class="phrase"><a name="boost_test.utf_reference.rt_param_reference.random.command_line_syntax"></a></span><a class="link" href="random.html#boost_test.utf_reference.rt_param_reference.random.command_line_syntax">Command 88 line syntax</a> 89 </h5> 90<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"> 91 <code class="computeroutput"><span class="special">--</span><span class="identifier">random</span><span class="special">=<</span><span class="identifier">seed</span><span class="special">></span></code> 92 </li></ul></div> 93<h5> 94<a name="boost_test.utf_reference.rt_param_reference.random.h2"></a> 95 <span class="phrase"><a name="boost_test.utf_reference.rt_param_reference.random.environment_variable"></a></span><a class="link" href="random.html#boost_test.utf_reference.rt_param_reference.random.environment_variable">Environment 96 variable</a> 97 </h5> 98<pre class="programlisting"><span class="identifier">BOOST_TEST_RANDOM</span> 99</pre> 100</div> 101<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 102<td align="left"></td> 103<td align="right"><div class="copyright-footer">Copyright © 2001-2020 Boost.Test contributors<p> 104 Distributed under the Boost Software License, Version 1.0. (See accompanying 105 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>) 106 </p> 107</div></td> 108</tr></table> 109<hr> 110<div class="spirit-nav"> 111<a accesskey="p" href="output_format.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../rt_param_reference.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="report_format.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 112</div> 113</body> 114</html> 115
