Let subproject tests use their own test fixture. Closes gh-867.

test/data/testrunner.js

@@ -7,6 +7,80 @@ jQuery.noConflict();
 // We remove Sizzle's globalization in jQuery
 var Sizzle = Sizzle || jQuery.find;
 
+// Allow subprojects to test against their own fixtures
+var qunitModule = QUnit.module;
+function testSubproject( label, url, risTests ) {
+	module( "Subproject: " + label );
+
+	module = QUnit.module = function( name ) {
+		return qunitModule.apply( this, [ label + ": " + name ].concat( [].slice.call( arguments, 1 ) ) );
+	};
+
+	test( "Copy test fixture", function() {
+		expect(3);
+
+		// Don't let subproject tests jump the gun
+		QUnit.config.reorder = false;
+
+		stop();
+		jQuery.ajax( url, {
+			dataType: "html",
+			error: function( jqXHR, status ) {
+				ok( false, "Retrieved test page: " + status );
+			},
+			success: function( data ) {
+				var page, fixture, fixtureHTML,
+					oldFixture = jQuery("#qunit-fixture");
+
+				ok( data, "Retrieved test page" );
+				try {
+					page = jQuery( jQuery.parseHTML(
+						data.replace( /(<\/?)(?:html|head)\b/g, "$1div" ),
+						document,
+						true
+					) );
+
+					// Get the fixture, including content outside of #qunit-fixture
+					fixture = page.find("[id='qunit-fixture']");
+					fixtureHTML = fixture.html();
+					fixture.empty();
+					while ( fixture.length && !fixture.prevAll("[id^='qunit-']").length ) {
+						fixture = fixture.parent();
+					}
+					fixture = fixture.add( fixture.nextAll() );
+					ok( fixture.html(), "Found test fixture" );
+
+					// Replace the current fixture, again including content outside of #qunit-fixture
+					while ( oldFixture.length && !oldFixture.prevAll("[id^='qunit-']").length ) {
+						oldFixture = oldFixture.parent();
+					}
+					oldFixture.nextAll().remove();
+					oldFixture.replaceWith( fixture );
+
+					// WARNING: UNDOCUMENTED INTERFACE
+					QUnit.config.fixture = fixtureHTML;
+					QUnit.reset();
+					equal( jQuery("#qunit-fixture").html(), fixtureHTML, "Copied test fixture" );
+
+					// Include subproject tests
+					page.find("script[src]").add( page.filter("script[src]") ).filter(function() {
+						var src = jQuery( this ).attr("src");
+						if ( risTests.test( src ) ) {
+							this.src = url + src;
+							return true;
+						}
+					}).appendTo("head:first");
+				} catch ( x ) {
+					ok( false, "Failed to copy test fixture: " + ( x.message || x ) );
+				}
+			},
+			complete: function() {
+				start();
+			}
+		});
+	});
+}
+
 /**
  * QUnit hooks
  */

test/index.html

@@ -40,8 +40,6 @@
 	<script src="unit/queue.js"></script>
 	<script src="unit/attributes.js"></script>
 	<script src="unit/event.js"></script>
-	<script src="../src/sizzle/test/unit/selector.js"></script>
-	<script src="../src/sizzle/test/unit/utilities.js"></script>
 	<script src="unit/selector.js"></script>
 	<script src="unit/traversing.js"></script>
 	<script src="unit/manipulation.js"></script>
@@ -54,6 +52,11 @@
 	<script src="unit/deprecated.js"></script>
 	<script src="unit/exports.js"></script>
 
+	<!-- Subproject tests must be last because they replace our test fixture -->
+	<script>
+		testSubproject( "Sizzle", "../src/sizzle/test/", /^unit\/.*\.js$/ );
+	</script>
+
 	<script>
 		// html5shiv, enabling HTML5 elements to be used with jQuery
 		( "abbr article aside audio bdi canvas data details figcaption figure footer header hgroup " +