casperChangeFilenameInXUnit.js

casper.test.currentTestFile = "otherFile.js";

casper.test.begin("test1", function suite(test){
	casper.start().then(function(){
		test.assert(true, "was true");
	}).run(function(){
		test.done();
	});
});

casper.test.begin("test2", function suite(test){
	var oldfile = test.currentTestFile;
	console.log("old file:", oldfile);
	test.currentTestFile = "newFile.js";
	casper.start().then(function(){
		test.assert(true, "was also true");
	}).run(function(){
		test.currentTestFile = oldfile;
		test.done();
	});
});

casper.test.begin("test3", function suite(test){
	casper.start().then(function(){
		test.assert(true, "was true, again (duh)");
	}).run(function(){
		test.done();
	});
});

resutl-xunit.xml

<?xml version="1.0" encoding="UTF-8"?>
<testsuites time="0.142">
	<testsuite name="test1" tests="1" failures="0" errors="0" time="0.067" timestamp="2014-07-01T15:45:38.759Z" package="otherFile">
		<testcase name="was true" classname="otherFile" time="0.067"/>
		<system-out/>
	</testsuite>
	<testsuite name="test2" tests="1" failures="0" errors="0" time="0.033" timestamp="2014-07-01T15:45:38.760Z" package="otherFile">
		<testcase name="was also true" classname="newFile" time="0.033"/>
		<system-out/>
	</testsuite>
	<testsuite name="test3" tests="1" failures="0" errors="0" time="0.042" timestamp="2014-07-01T15:45:38.760Z" package="otherFile">
		<testcase name="was true, again (duh)" classname="otherFile" time="0.042"/>
		<system-out/>
	</testsuite>
</testsuites>