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diff --git a/tools/NUnit/doc/exception.html b/tools/NUnit/doc/exception.html new file mode 100644 index 0000000..f3a23fc --- /dev/null +++ b/tools/NUnit/doc/exception.html @@ -0,0 +1,316 @@ +<!-- saved from url=(0014)about:internet --><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN"> +<html> +<!-- Standard Head Part --> +<head> +<title>NUnit - Exception</title> +<meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> +<meta http-equiv="Content-Language" content="en-US"> +<link rel="stylesheet" type="text/css" href="nunit.css"> +<link rel="shortcut icon" href="favicon.ico"> +</head> +<!-- End Standard Head Part --> + +<body> + +<!-- Standard Header for NUnit.org --> +<div id="header"> + <a id="logo" href="http://www.nunit.org"><img src="img/logo.gif" alt="NUnit.org" title="NUnit.org"></a> + <div id="nav"> + <a href="http://www.nunit.org">NUnit</a> + <a class="active" href="index.html">Documentation</a> + </div> +</div> +<!-- End of Header --> + +<div id="content"> + +<script language="JavaScript" src="codeFuncs.js" ></script> <!-- Do it this way for IE --> + +<h3>ExpectedExceptionAttribute (NUnit 2.0 plus Updates)</h3> + +<p>This is the way to specify that the execution of a test will throw an + exception. This attribute has a number of positional and + named parameters, which we will discuss in separate sections + according to the purpose they serve.</p> + +<h4>Specifying the Expected Exception Type</h4> + +<p>The original attribute, introduced with NUnit 2.0 took a single +argument giving the exact type of the expected exception. For example...</p> + + +<div class="code"><pre>[ExpectedException( typeof( ArgumentException ) )] +public void TestMethod() +{ +...</pre></div> + +<p>Beginning with NUnit 2.2.4, it became possible to specify the type +of exception as a string, avoiding the need for a reference to the +defining assembly...</p> + +<div class="code"><pre>[ExpectedException( "System.ArgumentException" ) )] +public void TestMethod() +{ +...</pre></div> + +<p>The above two examples function identically: the test only succeeds if a +System.Argument exception is thrown.</p> + +<h4>Specifying the Expected Message</h4> + +<p>NUnit 2.1 introduced a constructor with a second argument, specifying the +exact text of the message property of the exception. After NUnit 2.2.4, the +same extension was made to the constructor taking a string argument. With +NUnit 2.4, these arguments are marked obsolete, and a named parameter +is provided instead...</p> + +<div class="code" style="width: 44em"><pre>// Obsolete form: +[ExpectedException( typeof( ArgumentException ), "expected message" )] +[ExpectedException( "System.ArgumentException", "expected message" )] + +// Prefered form: +[ExpectedException( typeof( ArgumentException ), ExpectedMessage="expected message" )] +[ExpectedException( "System.ArgumentException", ExpectedMessage="expected message" )]</pre></div> + +<p>With NUnit 2.4, it is possible to specify additional tests on the +exception message, beyond a simple exact match. This is done using the +MatchType named parameter, whose argument is an enumeration, defined as +follows:</p> + +<div class="code"> +<pre>public enum MessageMatch +{ + /// Expect an exact match + Exact, + /// Expect a message containing the parameter string + Contains, + /// Match the regular expression provided as a parameter + Regex, + /// Expect a message starting with the parameter string + StartsWith +}</pre></div> + +<p>The following example is for a test that passes only if an ArgumentException +with a message containing "unspecified" is received.</p> + +<div class="code" style="width: 57em"> +<pre>[ExpectedException( typeof( ArgumentException), ExpectedMessage="unspecified", MatchType=MessageMatch.Contains )] +public void TestMethod() +{ +...</pre></div> + +<p>If MatchType is not specified, an exact match is used as before.</p> + +<h4>Specifying a Custom Error Message</h4> + +<p>With NUnit 2.4, it is possible to specify a custom message to be +displayed if the ExpectedException attribute is not satisfied. This +is done through the UserMessage named parameter...</p> + +<div class="code" style="width: 41em"> +<pre>[ExpectedException( typeof( ArgumentException ), UserMessage="Custom message" )] +public void TestMethod() +{ +...</pre> +</div> + +<h4>Handling the Exception in Code</h4> + +<p>If the processing required for an exception is too complex to express +in the attribute declaration, the normal practice is to process it in the +test code using a try/catch block. As an alternative, NUnit 2.4 allows +designating a method that will be called to process the exception. This +is particularly useful when multiple exceptions need to be processed +in the same way.</p> + +<p>An common exception handler may be designated by implementing the +<b>IExpectExceptionInterface</b>, which is defined as follows...</p> + +<div class="code"> +<pre>public interface IExpectException +{ + void HandleException( System.Exception ex ); +}</pre> +</div> + +<p>The exception handler is only called for methods marked with +the <b>ExpectedException</b> attribute. If all checks - including +the type of the exception - are to be performed in code, the +attribute may be specified without any arguments in order to +indicate that an exception is expected.</p> + +<p>An handler may be designated for a particular method +using the <b>Handler</b> named parameter.</p> + +<div class="code"><pre>[ExpectedException( Handler="HandlerMethod" )] +public void TestMethod() +{ +... +} + +public void HandlerMethod( System.Exception ex ) +{ +... +}</pre></div> + +<p>This technique may be +used without implementing <b>IExpectException</b> or in +combination with it. In the latter case, the designated handler +applies to any method that specifies it, while the normal +exception handler applies to any other methods that specify +an <b>ExpectedException</b>.</p> + +<p>However it is specified, the handler method should examine the exception and +<b>Assert</b> on whatever properties are relevant. Any resulting failure message +will then be consistent in format with other assertions performed in the tests.</p> + + +<h4>Example:</h4> + +<div class="code"> + +<div class="langFilter"> + <a href="javascript:Show('DD1')" onmouseover="Show('DD1')"><img src="img/langFilter.gif" width="14" height="14" alt="Language Filter"></a> + <div id="DD1" class="dropdown" style="display: none" onclick="Hide('DD1')"> + <a href="javascript:ShowCS()">C#</a><br> + <a href="javascript:ShowVB()">VB</a><br> + <a href="javascript:ShowMC()">C++</a><br> + </div> +</div> + +<pre class="cs">namespace NUnit.Tests +{ + using System; + using NUnit.Framework; + + [TestFixture] + public class SuccessTests + { + [Test] + [ExpectedException(typeof(InvalidOperationException))] + public void ExpectAnExceptionByType() + { /* ... */ } + + [Test] + [ExpectedException("System.InvalidOperationException")] + public void ExpectAnExceptionByName() + { /* ... */ } + } +} +</pre> + +<pre class="vb">Imports System +Imports Nunit.Framework + +Namespace Nunit.Tests + + <TestFixture()> Public Class SuccessTests + <Test(), ExpectedException(GetType(Exception))> + Public Sub ExpectAnExceptionByType() + ' ... + End Sub + + <TestFixture()> Public Class SuccessTests + <Test(), ExpectedException("System.Exception")> + Public Sub ExpectAnExceptionByName() + ' ... + End Sub + End Class +End Namespace +</pre> + +<pre class="mc">#using <Nunit.Framework.dll> +using namespace System; +using namespace NUnit::Framework; + +namespace NUnitTests +{ + [TestFixture] + public __gc class SuccessTests + { + [Test] + [ExpectedException(__typeof(InvalidOperationException))] + void ExpectAnExceptionByType(); + + [Test] + [ExpectedException(S"SystemInvalidOperationException")] + void ExpectAnExceptionByName(); + }; +} + +#include "cppsample.h" + +namespace NUnitTests { + // ... +} +</pre> + +</div> + +</div> + +<!-- Submenu --> +<div id="subnav"> +<ul> +<li><a href="index.html">NUnit 2.5.5</a></li> +<ul> +<li><a href="getStarted.html">Getting Started</a></li> +<li><a href="assertions.html">Assertions</a></li> +<li><a href="constraintModel.html">Constraints</a></li> +<li><a href="attributes.html">Attributes</a></li> +<ul> +<li><a href="category.html">Category</a></li> +<li><a href="combinatorial.html">Combinatorial</a></li> +<li><a href="culture.html">Culture</a></li> +<li><a href="datapoint.html">Datapoint(s)</a></li> +<li><a href="description.html">Description</a></li> +<li id="current"><a href="exception.html">Exception</a></li> +<li><a href="explicit.html">Explicit</a></li> +<li><a href="ignore.html">Ignore</a></li> +<li><a href="maxtime.html">Maxtime</a></li> +<li><a href="pairwise.html">Pairwise</a></li> +<li><a href="platform.html">Platform</a></li> +<li><a href="property.html">Property</a></li> +<li><a href="random.html">Random</a></li> +<li><a href="range.html">Range</a></li> +<li><a href="repeat.html">Repeat</a></li> +<li><a href="requiredAddin.html">RequiredAddin</a></li> +<li><a href="requiresMTA.html">Requires MTA</a></li> +<li><a href="requiresSTA.html">Requires STA</a></li> +<li><a href="requiresThread.html">Requires Thread</a></li> +<li><a href="sequential.html">Sequential</a></li> +<li><a href="setCulture.html">SetCulture</a></li> +<li><a href="setup.html">Setup</a></li> +<li><a href="setupFixture.html">SetupFixture</a></li> +<li><a href="suite.html">Suite</a></li> +<li><a href="teardown.html">Teardown</a></li> +<li><a href="test.html">Test</a></li> +<li><a href="testCase.html">TestCase</a></li> +<li><a href="testCaseSource.html">TestCaseSource</a></li> +<li><a href="testFixture.html">TestFixture</a></li> +<li><a href="fixtureSetup.html">TestFixtureSetUp</a></li> +<li><a href="fixtureTeardown.html">TestFixtureTearDown</a></li> +<li><a href="theory.html">Theory</a></li> +<li><a href="timeout.html">Timeout</a></li> +<li><a href="values.html">Values</a></li> +<li><a href="valueSource.html">ValueSource</a></li> +</ul> +<li><a href="runningTests.html">Running Tests</a></li> +<li><a href="extensibility.html">Extensibility</a></li> +<li><a href="releaseNotes.html">Release Notes</a></li> +<li><a href="samples.html">Samples</a></li> +<li><a href="license.html">License</a></li> +</ul> +</ul> +</div> +<!-- End of Submenu --> + + +<!-- Standard Footer for NUnit.org --> +<div id="footer"> + Copyright © 2009 Charlie Poole. 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