<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html xmlns:fn="http://www.w3.org/2005/02/xpath-functions">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link rel="stylesheet" href="../../../../doc/otp_doc.css" type="text/css">
<title>Erlang -- Code Coverage Analysis</title>
</head>
<body bgcolor="white" text="#000000" link="#0000ff" vlink="#ff00ff" alink="#ff0000"><div id="container">
<script id="js" type="text/javascript" language="JavaScript" src="../../../../doc/js/flipmenu/flipmenu.js"></script><script id="js2" type="text/javascript" src="../../../../doc/js/erlresolvelinks.js"></script><script language="JavaScript" type="text/javascript">
<!--
function getWinHeight() {
var myHeight = 0;
if( typeof( window.innerHeight ) == 'number' ) {
//Non-IE
myHeight = window.innerHeight;
} else if( document.documentElement && ( document.documentElement.clientWidth ||
document.documentElement.clientHeight ) ) {
//IE 6+ in 'standards compliant mode'
myHeight = document.documentElement.clientHeight;
} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
//IE 4 compatible
myHeight = document.body.clientHeight;
}
return myHeight;
}
function setscrollpos() {
var objf=document.getElementById('loadscrollpos');
document.getElementById("leftnav").scrollTop = objf.offsetTop - getWinHeight()/2;
}
function addEvent(obj, evType, fn){
if (obj.addEventListener){
obj.addEventListener(evType, fn, true);
return true;
} else if (obj.attachEvent){
var r = obj.attachEvent("on"+evType, fn);
return r;
} else {
return false;
}
}
addEvent(window, 'load', setscrollpos);
//--></script><div id="leftnav"><div class="innertube">
<img alt="Erlang logo" src="../../../../doc/erlang-logo.png"><br><small><a href="users_guide.html">User's Guide</a><br><a href="index.html">Reference Manual</a><br><a href="release_notes.html">Release Notes</a><br><a href="../pdf/common_test-1.6.3.pdf">PDF</a><br><a href="../../../../doc/index.html">Top</a></small><p><strong>Common Test</strong><br><strong>User's Guide</strong><br><small>Version 1.6.3</small></p>
<br><a href="javascript:openAllFlips()">Expand All</a><br><a href="javascript:closeAllFlips()">Contract All</a><p><small><strong>Chapters</strong></small></p>
<ul class="flipMenu" imagepath="../../../../doc/js/flipmenu">
<li id="no" title="Common Test Basics" expanded="false">Common Test Basics<ul>
<li><a href="basics_chapter.html">
Top of chapter
</a></li>
<li title="Introduction"><a href="basics_chapter.html#id66143">Introduction</a></li>
<li title="Test Suite Organisation"><a href="basics_chapter.html#id61412">Test Suite Organisation</a></li>
<li title="Support Libraries"><a href="basics_chapter.html#id67203">Support Libraries</a></li>
<li title="Suites and Test Cases"><a href="basics_chapter.html#id61632">Suites and Test Cases</a></li>
<li title="External Interfaces"><a href="basics_chapter.html#id63930">External Interfaces</a></li>
</ul>
</li>
<li id="no" title="Getting Started" expanded="false">Getting Started<ul>
<li><a href="getting_started_chapter.html">
Top of chapter
</a></li>
<li title="Are you new around here?"><a href="getting_started_chapter.html#id61356">Are you new around here?</a></li>
<li title="Test case execution"><a href="getting_started_chapter.html#id63050">Test case execution</a></li>
<li title="A simple test suite"><a href="getting_started_chapter.html#id63909">A simple test suite</a></li>
<li title="A test suite with configuration functions"><a href="getting_started_chapter.html#id68094">A test suite with configuration functions</a></li>
<li title="What happens next?"><a href="getting_started_chapter.html#id62545">What happens next?</a></li>
</ul>
</li>
<li id="no" title="Installation" expanded="false">Installation<ul>
<li><a href="install_chapter.html">
Top of chapter
</a></li>
<li title="General information"><a href="install_chapter.html#id66699">General information</a></li>
</ul>
</li>
<li id="no" title="Writing Test Suites" expanded="false">Writing Test Suites<ul>
<li><a href="write_test_chapter.html">
Top of chapter
</a></li>
<li title="Support for test suite authors"><a href="write_test_chapter.html#id71900">Support for test suite authors</a></li>
<li title="Test suites"><a href="write_test_chapter.html#id70761">Test suites</a></li>
<li title="Init and end per suite"><a href="write_test_chapter.html#id70806">Init and end per suite</a></li>
<li title="Init and end per test case"><a href="write_test_chapter.html#id70917">Init and end per test case</a></li>
<li title="Test cases"><a href="write_test_chapter.html#id71162">Test cases</a></li>
<li title="Test case info function"><a href="write_test_chapter.html#id71322">Test case info function</a></li>
<li title="Test suite info function"><a href="write_test_chapter.html#id71521">Test suite info function</a></li>
<li title="Test case groups"><a href="write_test_chapter.html#id71611">Test case groups</a></li>
<li title="The parallel property and nested groups"><a href="write_test_chapter.html#id72823">The parallel property and nested groups</a></li>
<li title="Parallel test cases and IO"><a href="write_test_chapter.html#id72860">Parallel test cases and IO</a></li>
<li title="Repeated groups"><a href="write_test_chapter.html#id72908">Repeated groups</a></li>
<li title="Shuffled test case order"><a href="write_test_chapter.html#id73046">Shuffled test case order</a></li>
<li title="Group info function"><a href="write_test_chapter.html#id73105">Group info function</a></li>
<li title="Info functions for init- and end-configuration"><a href="write_test_chapter.html#id73139">Info functions for init- and end-configuration</a></li>
<li title="Data and Private Directories"><a href="write_test_chapter.html#id73202">Data and Private Directories</a></li>
<li title="Execution environment"><a href="write_test_chapter.html#id73327">Execution environment</a></li>
<li title="Timetrap timeouts"><a href="write_test_chapter.html#id73364">Timetrap timeouts</a></li>
<li title="Logging - categories and verbosity levels"><a href="write_test_chapter.html#id73549">Logging - categories and verbosity levels</a></li>
<li title="Illegal dependencies"><a href="write_test_chapter.html#id73756">Illegal dependencies</a></li>
</ul>
</li>
<li id="no" title="Test Structure" expanded="false">Test Structure<ul>
<li><a href="test_structure_chapter.html">
Top of chapter
</a></li>
<li title="Test structure"><a href="test_structure_chapter.html#id73930">Test structure</a></li>
<li title="Skipping test cases"><a href="test_structure_chapter.html#id73944">Skipping test cases</a></li>
<li title="Definition of terms"><a href="test_structure_chapter.html#id74020">Definition of terms</a></li>
</ul>
</li>
<li id="no" title="Examples and Templates" expanded="false">Examples and Templates<ul>
<li><a href="example_chapter.html">
Top of chapter
</a></li>
<li title="Test suite example"><a href="example_chapter.html#id74246">Test suite example</a></li>
<li title="Test suite templates"><a href="example_chapter.html#id74298">Test suite templates</a></li>
</ul>
</li>
<li id="no" title="Running Tests" expanded="false">Running Tests<ul>
<li><a href="run_test_chapter.html">
Top of chapter
</a></li>
<li title="Using the Common Test Framework"><a href="run_test_chapter.html#id74488">Using the Common Test Framework</a></li>
<li title="Automatic compilation of test suites and help modules"><a href="run_test_chapter.html#id74528">Automatic compilation of test suites and help modules</a></li>
<li title="Running tests from the OS command line"><a href="run_test_chapter.html#id74645">Running tests from the OS command line</a></li>
<li title="Running tests from the Erlang shell or from an Erlang program"><a href="run_test_chapter.html#id75142">Running tests from the Erlang shell or from an Erlang program</a></li>
<li title="Test case group execution"><a href="run_test_chapter.html#id75304">Test case group execution</a></li>
<li title="Running the interactive shell mode"><a href="run_test_chapter.html#id75821">Running the interactive shell mode</a></li>
<li title="Step by step execution of test cases with the Erlang Debugger"><a href="run_test_chapter.html#id76003">Step by step execution of test cases with the Erlang Debugger</a></li>
<li title="Test Specifications"><a href="run_test_chapter.html#id76102">Test Specifications</a></li>
<li title="Running tests from the Web based GUI"><a href="run_test_chapter.html#id76643">Running tests from the Web based GUI</a></li>
<li title="Log files"><a href="run_test_chapter.html#id76735">Log files</a></li>
<li title="HTML Style Sheets"><a href="run_test_chapter.html#id77053">HTML Style Sheets</a></li>
<li title="Repeating tests"><a href="run_test_chapter.html#id77201">Repeating tests</a></li>
<li title="Silent Connections"><a href="run_test_chapter.html#id77412">Silent Connections</a></li>
</ul>
</li>
<li id="no" title="External Configuration Data" expanded="false">External Configuration Data<ul>
<li><a href="config_file_chapter.html">
Top of chapter
</a></li>
<li title="General"><a href="config_file_chapter.html#id77631">General</a></li>
<li title="Syntax"><a href="config_file_chapter.html#id77671">Syntax</a></li>
<li title="Requiring and reading configuration data"><a href="config_file_chapter.html#id77695">Requiring and reading configuration data</a></li>
<li title="Using configuration variables defined in multiple files"><a href="config_file_chapter.html#id77839">Using configuration variables defined in multiple files</a></li>
<li title="Encrypted configuration files"><a href="config_file_chapter.html#id77870">Encrypted configuration files</a></li>
<li title="Opening connections by using configuration data"><a href="config_file_chapter.html#id77934">Opening connections by using configuration data</a></li>
<li title="User specific configuration data formats"><a href="config_file_chapter.html#id78002">User specific configuration data formats</a></li>
<li title="Examples of configuration data handling"><a href="config_file_chapter.html#id78216">Examples of configuration data handling</a></li>
<li title="Example of user specific configuration handler"><a href="config_file_chapter.html#id78268">Example of user specific configuration handler</a></li>
</ul>
</li>
<li id="loadscrollpos" title="Code Coverage Analysis" expanded="true">Code Coverage Analysis<ul>
<li><a href="cover_chapter.html">
Top of chapter
</a></li>
<li title="General"><a href="cover_chapter.html#id78384">General</a></li>
<li title="Usage"><a href="cover_chapter.html#id78404">Usage</a></li>
<li title="The cover specification file"><a href="cover_chapter.html#id78510">The cover specification file</a></li>
<li title="Logging"><a href="cover_chapter.html#id78563">Logging</a></li>
</ul>
</li>
<li id="no" title="Using Common Test for Large Scale Testing" expanded="false">Using Common Test for Large Scale Testing<ul>
<li><a href="ct_master_chapter.html">
Top of chapter
</a></li>
<li title="General"><a href="ct_master_chapter.html#id78634">General</a></li>
<li title="Usage"><a href="ct_master_chapter.html#id78668">Usage</a></li>
<li title="Test Specifications"><a href="ct_master_chapter.html#id78815">Test Specifications</a></li>
<li title="Automatic startup of test target nodes"><a href="ct_master_chapter.html#id78987">Automatic startup of test target nodes</a></li>
</ul>
</li>
<li id="no" title="Event Handling" expanded="false">Event Handling<ul>
<li><a href="event_handler_chapter.html">
Top of chapter
</a></li>
<li title="General"><a href="event_handler_chapter.html#id79190">General</a></li>
<li title="Usage"><a href="event_handler_chapter.html#id79226">Usage</a></li>
</ul>
</li>
<li id="no" title="Dependencies between Test Cases and Suites" expanded="false">Dependencies between Test Cases and Suites<ul>
<li><a href="dependencies_chapter.html">
Top of chapter
</a></li>
<li title="General"><a href="dependencies_chapter.html#id80143">General</a></li>
<li title="Saving configuration data"><a href="dependencies_chapter.html#id80265">Saving configuration data</a></li>
<li title="Sequences"><a href="dependencies_chapter.html#id80430">Sequences</a></li>
</ul>
</li>
<li id="no" title="Common Test Hooks" expanded="false">Common Test Hooks<ul>
<li><a href="ct_hooks_chapter.html">
Top of chapter
</a></li>
<li title="General"><a href="ct_hooks_chapter.html#id80622">General</a></li>
<li title="Installing a CTH"><a href="ct_hooks_chapter.html#id80676">Installing a CTH</a></li>
<li title="CTH Scope"><a href="ct_hooks_chapter.html#id80835">CTH Scope</a></li>
<li title="Manipulating tests"><a href="ct_hooks_chapter.html#id81189">Manipulating tests</a></li>
<li title="Example CTH"><a href="ct_hooks_chapter.html#id81482">Example CTH</a></li>
<li title="Built-in CTHs"><a href="ct_hooks_chapter.html#id81535">Built-in CTHs</a></li>
</ul>
</li>
<li id="no" title="Some thoughts about testing" expanded="false">Some thoughts about testing<ul>
<li><a href="why_test_chapter.html">
Top of chapter
</a></li>
<li title="Goals"><a href="why_test_chapter.html#id81722">Goals</a></li>
<li title="What to test?"><a href="why_test_chapter.html#id81742">What to test?</a></li>
</ul>
</li>
</ul>
</div></div>
<div id="content">
<div class="innertube">
<h1>9 Code Coverage Analysis</h1>
<h3><a name="id78384">9.1
General</a></h3>
<a name="cover"></a>
<p>Although Common Test was created primarly for the purpose of
black box testing, nothing prevents it from working perfectly as
a white box testing tool as well. This is especially true when
the application to test is written in Erlang. Then the test
ports are easily realized by means of Erlang function calls.</p>
<p>When white box testing an Erlang application, it is useful to
be able to measure the code coverage of the test. Common Test
provides simple access to the OTP Cover tool for this
purpose. Common Test handles all necessary communication with
the Cover tool (starting, compiling, analysing, etc). All the
Common Test user needs to do is to specify the extent of the
code coverage analysis.</p>
<h3><a name="id78404">9.2
Usage</a></h3>
<p>To specify what modules should be included
in the code coverage test, you provide a cover specification
file. Using this file you can point out specific modules or
specify directories that contain modules which should all be
included in the analysis. You can also, in the same fashion,
specify modules that should be excluded from the analysis.</p>
<p>If you are testing a distributed Erlang application, it is
likely that code you want included in the code coverage analysis
gets executed on an Erlang node other than the one Common Test
is running on. If this is the case you need to specify these
other nodes in the cover specification file or add them
dynamically to the code coverage set of nodes. See the
<span class="code">ct_cover</span> page in the reference manual for details on the
latter.</p>
<p>In the cover specification file you can also specify your
required level of the code coverage analysis; <span class="code">details</span> or
<span class="code">overview</span>. In detailed mode, you get a coverage overview
page, showing you per module and total coverage percentages, as
well as one HTML file printed for each module included in the
analysis that shows exactly what parts of the code have been
executed during the test. In overview mode, only the code
coverage overview page gets printed.</p>
<p><strong>Note:</strong> Currently, for Common Test to be able to print
code coverage HTML files for the modules included in the
analysis, the source code files of these modules must be
located in the same directory as the corresponding <span class="code">.beam</span>
files. This is a limitation that will be removed later.</p>
<p>You can choose to export and import code coverage data between
tests. If you specify the name of an export file in the cover
specification file, Common Test will export collected coverage
data to this file at the end of the test. You may similarly
specify that previously exported data should be imported and
included in the analysis for a test (you can specify multiple
import files). This way it is possible to analyse total code coverage
without necessarily running all tests at once. Note that even if
you run separate tests in one test run, code coverage data will
not be passed on from one test to another unless you specify an
export file for Common Test to use for this purpose.</p>
<p>To activate the code coverage support, you simply specify the
name of the cover specification file as you start Common Test.
This you do either by using the <span class="code">-cover</span> flag with <span class="code">ct_run</span>.
Example:</p>
<p><span class="code">$ ct_run -dir $TESTOBJS/db -cover $TESTOBJS/db/config/db.coverspec</span></p>
<p>You may also pass the cover specification file name in a
call to <span class="code"><span class="bold_code"><a href="ct.html#run_test-1">ct:run_test/1</a></span></span>, by adding a <span class="code">{cover,CoverSpec}</span>
tuple to the <span class="code">Opts</span> argument. Also, you can of course
enable code coverage in your test specifications (read
more in the chapter about
<span class="bold_code"><a href="run_test_chapter.html#test_specifications">using test
specifications</a></span>).</p>
<h3><a name="id78510">9.3
The cover specification file</a></h3>
<p>These are the terms allowed in a cover specification file:</p>
<div class="example"><pre>
%% List of Nodes on which cover will be active during test.
%% Nodes = [atom()]
{nodes, Nodes}.
%% Files with previously exported cover data to include in analysis.
%% CoverDataFiles = [string()]
{import, CoverDataFiles}.
%% Cover data file to export from this session.
%% CoverDataFile = string()
{export, CoverDataFile}.
%% Cover analysis level.
%% Level = details | overview
{level, Level}.
%% Directories to include in cover.
%% Dirs = [string()]
{incl_dirs, Dirs}.
%% Directories, including subdirectories, to include.
{incl_dirs_r, Dirs}.
%% Specific modules to include in cover.
%% Mods = [atom()]
{incl_mods, Mods}.
%% Directories to exclude in cover.
{excl_dirs, Dirs}.
%% Directories, including subdirectories, to exclude.
{excl_dirs_r, Dirs}.
%% Specific modules to exclude in cover.
{excl_mods, Mods}.
</pre></div>
<p>The <span class="code">incl_dirs_r</span> and <span class="code">excl_dirs_r</span> terms tell Common
Test to search the given directories recursively and include
or exclude any module found during the search. The
<span class="code">incl_dirs</span> and <span class="code">excl_dirs</span> terms result in a
non-recursive search for modules (i.e. only modules found in
the given directories are included or excluded).</p>
<p><strong>Note:</strong> Directories containing Erlang modules that are
to be included in a code coverage test must exist in the code
server path, or the cover tool will fail to recompile the modules.
(It is not sufficient to specify these directories in the cover
specification file for Common Test).</p>
<h3><a name="id78563">9.4
Logging</a></h3>
<p>To view the result of a code coverage test, follow the
"Coverage log" link on the test suite results page. This
takes you to the code coverage overview page. If you have
successfully performed a detailed coverage analysis, you
find links to each individual module coverage page here.</p>
</div>
<div class="footer">
<hr>
<p>Copyright © 2003-2012 Ericsson AB. All Rights Reserved.</p>
</div>
</div>
</div></body>
</html>
distrib
>
Fedora
>
17
>
i386
>
media
>
updates
>
by-pkgid
>
675c8c8167236dfcf8d66da674f931e8
>
files
>
234
