To use MSBuild to build .NET projects and test them with nUnit you need the following:

Preparation Step:
Download to Build Machine:

ANT .NET library from http://ant.apache.org/antlibs/dotnet/
.NET Framework from http://www.microsoft.com/net/Download.aspx
NUnit from http://nunit.org/index.php?p=download

Installation on Build Machine:

Install ANT .NET library into ant/lib
Install .NET Framework
Install NUnit Package

You will also need to provide other required tools and any dependencies for your build, Set environment variables and so on.

Setup your build engine, build user, build respository workspace as described on jazz.net in artikel
Getting started with Setting up jazz builds.

Step 1 : Add the definition for the ANT .NET Library:
<project default="all" name="HelloWorld" xmlns:dn="antlib:org.apache.ant.dotnet">

Step 2 : Call MSBuild with the appropriate Visual Studio Solution file (using the default settings).
<dn:msbuild buildfile="Helloworld.net.sln" />

Step 3 : Execute NUnit to run unit tests
However, you could also use the NUnit Task provided by the dotNet Antlibs. NUnit creates the test output like JUnit but in a different format
<exec executable="${nunit.path}${nunit.exec}">
<arg value="${nunit.testfile}"/>
<arg value="/xml=${nunit.xmlfile}"/>
</exec>

Step 4 : Transform the NUnit output file a JUnit compatible format, and tell the JUnit logpublisher where to get the outputfile.
<xslt in="${nunit.xmlfile}" out="${nunit.transfomedfile}" style="${nunit.transformation}" />
<junitLogPublisher filePath="${nunit.transfomedfile}" buildResultUUID="${buildResultUUID}" repositoryAddress="${repositoryAddress}" userId="${userId}" password="${password}" />

Now running a build also shows you the NUnit results (as JUnit)

Sample build file:
<?xml version="1.0" encoding="UTF-8"?>


<project default="all" name="HelloWorld" xmlns:dn="antlib:org.apache.ant.dotnet">


<target name="all">
<!-- userid and password of the build engine -->
<property name="userId" value="userid" />
<property name="password" value="yourtopsecretpwd" />

<property name="compileLog" value="${basedir}/compile.xml" />

<startBuildActivity activityIdProperty="Build" label="building..." buildResultUUID="${buildResultUUID}" repositoryAddress="${repositoryAddress}" userId="${userId}" password="${password}" />
<dn:msbuild buildfile="Helloworld.net.sln" />
<completeBuildActivity activityId="${Build}" buildResultUUID="${buildResultUUID}" repositoryAddress="${repositoryAddress}" userId="${userId}" password="${password}" />

<startBuildActivity activityIdProperty="Test" label="testing..." buildResultUUID="${buildResultUUID}" repositoryAddress="${repositoryAddress}" userId="${userId}" password="${password}" />
<property name="nunit.path" value="C:\Program Files\NUnit 2.5.1\bin\net-2.0\"/>
<property name="nunit.exec" value="nunit-console.exe"/>
<property name="nunit.testfile" value="D:\BuildEngine\RTC pilot\Workspace\net-fetched\HelloWorld.Net\HelloworldTest\bin\Debug\HelloworldTest.exe"/>
<property name="nunit.xmlfile" value="D:\BuildEngine\RTC pilot\Workspace\net-fetched\HelloWorld.Net\nunit.xml"/>

<exec executable="${nunit.path}${nunit.exec}">
<arg value="${nunit.testfile}"/>
<arg value="/xml=${nunit.xmlfile}"/>
</exec>
<junitLogPublisher filePath="${nunit.xmlfile}" buildResultUUID="${buildResultUUID}" repositoryAddress="${repositoryAddress}" userId="${userId}" password="${password}" />
<completeBuildActivity activityId="${Test}" buildResultUUID="${buildResultUUID}" repositoryAddress="${repositoryAddress}" userId="${userId}" password="${password}" />

</target>
<taskdef name="junitLogPublisher" classname="com.ibm.team.build.ant.task.JUnitLogPublisherTask" />
<taskdef name="logPublisher" classname="com.ibm.team.build.ant.task.LogPublisherTask" />
<taskdef name="startBuildActivity" classname="com.ibm.team.build.ant.task.StartBuildActivityTask" />
<taskdef name="completeBuildActivity" classname="com.ibm.team.build.ant.task.CompleteBuildActivityTask" />

</project>

Sample XSLT to transform NUnit to JUnit:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" indent="yes" encoding="utf-8" version="1.0" cdata-section-elements="failure" />
<xsl:template match="test-results/test-suite">
<xsl:variable name="nErrors" select="//test-results/@errors"/>
<xsl:variable name="nFailures" select="//test-results/@failures"/>
<xsl:variable name="nTotal" select="//test-results/@total"/>
<xsl:variable name ="nHostName" select="//test-results/environment/@machine-name"/>
<xsl:variable name="testcases" select="//test-suite"/>
<testsuite name="{//test-suite/@name}" time="{@time}" tests="{$nTotal}" errors="{$nErrors}" failures="{$nFailures}" hostname="{$nHostName}">
<xsl:for-each select="$testcases">
<xsl:variable name="suite" select="."/>
<xsl:variable name="generalfailure" select="./failure"/>
<xsl:for-each select=".//test-case">
<testcase classname="{./@name}" name="{./@name}" time="{./@time}">
<xsl:if test="./failure">
<xsl:variable name="failstack" select="count(./failure/stack-trace/*) + count(./failure/stack-trace/text())"/>
<failure type="nunit.not.reported">
<xsl:choose>
<xsl:when test="$failstack > 0 or not($generalfailure)">
MESSAGE: <xsl:value-of select="./failure/message"/>
+++++++++++++++++++
STACK TRACE: <xsl:value-of select="./failure/stack-trace"/>
</xsl:when>
<xsl:otherwise>
MESSAGE: <xsl:value-of select="$generalfailure/message"/>
+++++++++++++++++++
STACK TRACE: <xsl:value-of select="$generalfailure/stack-trace"/>
</xsl:otherwise>
</xsl:choose>
</failure>
</xsl:if>
</testcase>
</xsl:for-each>
</xsl:for-each>
</testsuite>
</xsl:template>
</xsl:stylesheet>

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