Core: Remove IE-specific support tests, rely on document.documentMode

Also, update some tests to IE-sniff when deciding whether
to skip a test.

Fixes gh-4386
Closes gh-4387

src/ajax.js

@@ -458,6 +458,12 @@ jQuery.extend( {
 						if ( !responseHeaders ) {
 							responseHeaders = {};
 							while ( ( match = rheaders.exec( responseHeadersString ) ) ) {
+
+								// Support: IE 11+
+								// `getResponseHeader( key )` in IE doesn't combine all header
+								// values for the provided key into a single result with values
+								// joined by commas as other browsers do. Instead, it returns
+								// them on separate lines.
 								responseHeaders[ match[ 1 ].toLowerCase() + " " ] =
 									( responseHeaders[ match[ 1 ].toLowerCase() + " " ] || [] )
 										.concat( match[ 2 ] );

src/attributes/attr.js

@@ -2,10 +2,10 @@ define( [
 	"../core",
 	"../core/access",
 	"../core/nodeName",
-	"./support",
 	"../var/rnothtmlwhite",
+	"../var/isIE",
 	"../selector"
-], function( jQuery, access, nodeName, support, rnothtmlwhite ) {
+], function( jQuery, access, nodeName, rnothtmlwhite, isIE ) {
 
 "use strict";
 
@@ -74,8 +74,10 @@ jQuery.extend( {
 	attrHooks: {
 		type: {
 			set: function( elem, value ) {
-				if ( !support.radioValue && value === "radio" &&
+
-					nodeName( elem, "input" ) ) {
+				// Support: IE <=11+
+				// An input loses its value after becoming a radio
+				if ( isIE && value === "radio" && nodeName( elem, "input" ) ) {
 					var val = elem.value;
 					elem.setAttribute( "type", value );
 					if ( val ) {

src/attributes/prop.js

@@ -1,9 +1,9 @@
 define( [
 	"../core",
 	"../core/access",
-	"./support",
+	"../var/isIE",
 	"../selector"
-], function( jQuery, access, support ) {
+], function( jQuery, access, isIE ) {
 
 "use strict";
 
@@ -90,14 +90,11 @@ jQuery.extend( {
 } );
 
 // Support: IE <=11+
-// Accessing the selectedIndex property
+// Accessing the selectedIndex property forces the browser to respect
-// forces the browser to respect setting selected
+// setting selected on the option. The getter ensures a default option
-// on the option
+// is selected when in an optgroup. ESLint rule "no-unused-expressions"
-// The getter ensures a default option is selected
+// is disabled for this code since it considers such accessions noop.
-// when in an optgroup
+if ( isIE ) {
-// eslint rule "no-unused-expressions" is disabled for this code
-// since it considers such accessions noop
-if ( !support.optSelected ) {
 	jQuery.propHooks.selected = {
 		get: function( elem ) {
 

src/attributes/support.js

@@ -1,29 +0,0 @@
-define( [
-	"../var/document",
-	"../var/support"
-], function( document, support ) {
-
-"use strict";
-
-( function() {
-	var input = document.createElement( "input" ),
-		select = document.createElement( "select" ),
-		opt = select.appendChild( document.createElement( "option" ) );
-
-	input.type = "checkbox";
-
-	// Support: IE <=11+
-	// Must access selectedIndex to make default options select
-	support.optSelected = opt.selected;
-
-	// Support: IE <=11+
-	// An input loses its value after becoming a radio
-	input = document.createElement( "input" );
-	input.value = "t";
-	input.type = "radio";
-	support.radioValue = input.value === "t";
-} )();
-
-return support;
-
-} );

src/css.js

@@ -2,6 +2,7 @@ define( [
 	"./core",
 	"./core/access",
 	"./var/rcssNum",
+	"./var/isIE",
 	"./css/var/rnumnonpx",
 	"./css/var/cssExpand",
 	"./css/isAutoPx",
@@ -10,14 +11,13 @@ define( [
 	"./css/var/swap",
 	"./css/curCSS",
 	"./css/adjustCSS",
-	"./css/support",
 	"./css/finalPropName",
 
 	"./core/init",
 	"./core/ready",
 	"./selector" // contains
-], function( jQuery, access, rcssNum, rnumnonpx, cssExpand, isAutoPx, cssCamelCase,
+], function( jQuery, access, rcssNum, isIE, rnumnonpx, cssExpand, isAutoPx,
-	getStyles, swap, curCSS, adjustCSS, support, finalPropName ) {
+	cssCamelCase, getStyles, swap, curCSS, adjustCSS, finalPropName ) {
 
 "use strict";
 
@@ -121,7 +121,7 @@ function getWidthOrHeight( elem, dimension, extra ) {
 
 		// To avoid forcing a reflow, only fetch boxSizing if we need it (gh-4322).
 		// Fake content-box until we know it's needed to know the true value.
-		boxSizingNeeded = !support.boxSizingReliable() || extra,
+		boxSizingNeeded = isIE || extra,
 		isBorderBox = boxSizingNeeded &&
 			jQuery.css( elem, "boxSizing", false, styles ) === "border-box",
 		valueIsBorderBox = isBorderBox,
@@ -140,11 +140,12 @@ function getWidthOrHeight( elem, dimension, extra ) {
 
 	// Fall back to offsetWidth/offsetHeight when value is "auto"
 	// This happens for inline elements with no explicit setting (gh-3571)
+	//
 	// Support: IE 9 - 11+
 	// Also use offsetWidth/offsetHeight for when box sizing is unreliable
 	// We use getClientRects() to check for hidden/disconnected.
 	// In those cases, the computed value can be trusted to be border-box
-	if ( ( !support.boxSizingReliable() && isBorderBox || val === "auto" ) &&
+	if ( ( isIE && isBorderBox || val === "auto" ) &&
 		elem.getClientRects().length ) {
 
 		isBorderBox = jQuery.css( elem, "boxSizing", false, styles ) === "border-box";
@@ -239,8 +240,9 @@ jQuery.extend( {
 				value += ret && ret[ 3 ] || ( isAutoPx( origName ) ? "px" : "" );
 			}
 
-			// background-* props affect original clone's values
+			// Support: IE <=9 - 11+
-			if ( !support.clearCloneStyle && value === "" && name.indexOf( "background" ) === 0 ) {
+			// background-* props of a cloned element affect the source element (#8908)
+			if ( isIE && value === "" && name.indexOf( "background" ) === 0 ) {
 				style[ name ] = "inherit";
 			}
 

src/css/support.js

@@ -1,60 +0,0 @@
-define( [
-	"../core",
-	"../var/document",
-	"../var/documentElement",
-	"../var/support"
-], function( jQuery, document, documentElement, support ) {
-
-"use strict";
-
-( function() {
-
-	var boxSizingReliableVal,
-		container = document.createElement( "div" ),
-		div = document.createElement( "div" );
-
-	// Finish early in limited (non-browser) environments
-	if ( !div.style ) {
-		return;
-	}
-
-	// Support: IE <=9 - 11+
-	// Style of cloned element affects source element cloned (#8908)
-	div.style.backgroundClip = "content-box";
-	div.cloneNode( true ).style.backgroundClip = "";
-	support.clearCloneStyle = div.style.backgroundClip === "content-box";
-
-	jQuery.extend( support, {
-		boxSizingReliable: function() {
-
-			// This is a singleton, we need to execute it only once
-			if ( div ) {
-				container.style.cssText = "position:absolute;left:-11111px;width:60px;" +
-					"margin-top:1px;padding:0;border:0";
-				div.style.cssText =
-					"position:relative;display:block;box-sizing:border-box;overflow:scroll;" +
-					"margin:auto;border:1px;padding:1px;" +
-					"width:60%;top:1%";
-				documentElement.appendChild( container ).appendChild( div );
-
-				var divStyle = window.getComputedStyle( div );
-
-				// Support: IE 9 - 11+
-				// Detect misreporting of content dimensions for box-sizing:border-box elements
-				boxSizingReliableVal = Math.round( parseFloat( divStyle.width ) ) === 36;
-
-				documentElement.removeChild( container );
-
-				// Nullify the div so it wouldn't be stored in the memory and
-				// it will also be a sign that checks already performed
-				div = null;
-			}
-
-			return boxSizingReliableVal;
-		}
-	} );
-} )();
-
-return support;
-
-} );

src/manipulation.js

@@ -2,6 +2,7 @@ define( [
 	"./core",
 	"./core/isAttached",
 	"./var/concat",
+	"./var/isIE",
 	"./var/push",
 	"./var/rcheckableType",
 	"./core/access",
@@ -11,7 +12,6 @@ define( [
 	"./manipulation/getAll",
 	"./manipulation/setGlobalEval",
 	"./manipulation/buildFragment",
-	"./manipulation/support",
 
 	"./data/var/dataPriv",
 	"./data/var/dataUser",
@@ -23,9 +23,9 @@ define( [
 	"./traversing",
 	"./selector",
 	"./event"
-], function( jQuery, isAttached, concat, push, rcheckableType,
+], function( jQuery, isAttached, concat, isIE, push,
-	access, rtagName, rscriptType,
+	rcheckableType, access, rtagName, rscriptType,
-	wrapMap, getAll, setGlobalEval, buildFragment, support,
+	wrapMap, getAll, setGlobalEval, buildFragment,
 	dataPriv, dataUser, acceptData, DOMEval, nodeName ) {
 
 "use strict";
@@ -222,7 +222,7 @@ jQuery.extend( {
 			inPage = isAttached( elem );
 
 		// Fix IE cloning issues
-		if ( !support.noCloneChecked && ( elem.nodeType === 1 || elem.nodeType === 11 ) &&
+		if ( isIE && ( elem.nodeType === 1 || elem.nodeType === 11 ) &&
 				!jQuery.isXMLDoc( elem ) ) {
 
 			// We eschew Sizzle here for performance reasons: https://jsperf.com/getall-vs-sizzle/2
@@ -233,7 +233,7 @@ jQuery.extend( {
 
 				// Support: IE <=11+
 				// IE fails to set the defaultValue to the correct value when
-				// cloning other types of input fields
+				// cloning textareas.
 				if ( destElements[ i ].nodeName.toLowerCase() === "textarea" ) {
 					destElements[ i ].defaultValue = srcElements[ i ].defaultValue;
 				}

src/manipulation/support.js

@@ -1,28 +0,0 @@
-define( [
-	"../var/document",
-	"../var/support"
-], function( document, support ) {
-
-"use strict";
-
-( function() {
-	var fragment = document.createDocumentFragment(),
-		div = fragment.appendChild( document.createElement( "div" ) ),
-		input = document.createElement( "input" );
-
-	// Support: Windows Web Apps (WWA)
-	// `name` and `type` must use .setAttribute for WWA (#14901)
-	input.setAttribute( "type", "radio" );
-	input.setAttribute( "checked", "checked" );
-
-	div.appendChild( input );
-
-	// Support: IE <=11+
-	// Make sure textarea (and checkbox) defaultValue is properly cloned
-	div.innerHTML = "<textarea>x</textarea>";
-	support.noCloneChecked = !!div.cloneNode( true ).lastChild.defaultValue;
-} )();
-
-return support;
-
-} );

src/var/isIE.js

@@ -0,0 +1,7 @@
+define( [
+	"./document"
+], function( document ) {
+	"use strict";
+
+	return document.documentMode;
+} );

test/data/inner_nomodule.js

@@ -1 +1 @@
-QUnit.assert.ok( !QUnit.moduleTypeSupported, "evaluated: inner nomodule script with src" );
+QUnit.assert.ok( QUnit.isIE, "evaluated: inner nomodule script with src" );

test/data/nomodule.js

@@ -1 +1 @@
-QUnit.assert.ok( !QUnit.moduleTypeSupported, "evaluated: nomodule script with src" );
+QUnit.assert.ok( QUnit.isIE, "evaluated: nomodule script with src" );

test/data/testinit-jsdom.js

@@ -4,6 +4,9 @@
 // jsdom implements a throwing `window.scrollTo`.
 QUnit.config.scrolltop = false;
 
+QUnit.isIE = false;
+QUnit.testUnlessIE = QUnit.test;
+
 const FILEPATH = "/test/data/testinit-jsdom.js";
 const activeScript = document.currentScript;
 const parentUrl = activeScript && activeScript.src ?

test/data/testinit.js

@@ -256,14 +256,11 @@ if ( !window.__karma__ ) {
 QUnit.isSwarm = ( QUnit.urlParams.swarmURL + "" ).indexOf( "http" ) === 0;
 QUnit.basicTests = ( QUnit.urlParams.module + "" ) === "basic";
 
-// Async test for module script type support
+// Support: IE 11+
-function moduleTypeSupported() {
+// A variable to make it easier to skip specific tests in IE, mostly
-	var script = document.createElement( "script" );
+// testing integrations with newer Web features not supported by it.
-	script.type = "module";
+QUnit.isIE = !!window.document.documentMode;
-	script.text = "QUnit.moduleTypeSupported = true";
+QUnit.testUnlessIE = QUnit.isIE ? QUnit.skip : QUnit.test;
-	document.head.appendChild( script ).parentNode.removeChild( script );
-}
-moduleTypeSupported();
 
 this.loadTests = function() {
 

test/middleware-mockserver.js

@@ -138,7 +138,7 @@ var mocks = {
 			"constructor": "prototype collision (constructor)"
 		} );
 		req.query.keys.split( "|" ).forEach( function( key ) {
-			if ( req.headers[ key.toLowerCase() ] ) {
+			if ( key.toLowerCase() in req.headers ) {
 				resp.write( key + ": " + req.headers[ key.toLowerCase() ] + "\n" );
 			}
 		} );

test/unit/ajax.js

@@ -260,7 +260,7 @@ QUnit.module( "ajax", {
 				} );
 			},
 			url: url( "mock.php?action=headers&keys=siMPle|SometHing-elsE|OthEr|Nullable|undefined|Empty|ajax-send" ),
-			headers: {
+			headers: supportjQuery.extend( {
 				"siMPle": "value",
 				"SometHing-elsE": "other value",
 				"OthEr": "something else",
@@ -268,11 +268,12 @@ QUnit.module( "ajax", {
 				"undefined": undefined
 
 				// Support: IE 9 - 11+, Edge 12 - 14 only
-				// Not all browsers allow empty-string headers
+				// IE can receive empty headers but not send them.
-				//"Empty": ""
+			}, QUnit.isIE ? {} : {
-			},
+				"Empty": ""
+			} ),
 			success: function( data, _, xhr ) {
-				var i, emptyHeader,
+				var i,
 					requestHeaders = jQuery.extend( this.headers, {
 						"ajax-send": "test"
 					} ),
@@ -285,13 +286,7 @@ QUnit.module( "ajax", {
 				assert.strictEqual( data, tmp, "Headers were sent" );
 				assert.strictEqual( xhr.getResponseHeader( "Sample-Header" ), "Hello World", "Sample header received" );
 				assert.ok( data.indexOf( "undefined" ) < 0, "Undefined header value was not sent" );
-
+				assert.strictEqual( xhr.getResponseHeader( "Empty-Header" ), "", "Empty header received" );
-				emptyHeader = xhr.getResponseHeader( "Empty-Header" );
-				if ( emptyHeader === null ) {
-					assert.ok( true, "Firefox doesn't support empty headers" );
-				} else {
-					assert.strictEqual( emptyHeader, "", "Empty header received" );
-				}
 				assert.strictEqual( xhr.getResponseHeader( "Sample-Header2" ), "Hello World 2", "Second sample header received" );
 				assert.strictEqual( xhr.getResponseHeader( "List-Header" ), "Item 1, Item 2", "List header received" );
 				assert.strictEqual( xhr.getResponseHeader( "constructor" ), "prototype collision (constructor)", "constructor header received" );

test/unit/attributes.js

@@ -989,29 +989,37 @@ QUnit.test( "val() with non-matching values on dropdown list", function( assert
 	select6.remove();
 } );
 
-if ( "value" in document.createElement( "meter" ) &&
+QUnit.test( "val() respects numbers without exception (Bug #9319) - progress",
-			"value" in document.createElement( "progress" ) ) {
+	function( assert ) {
 
-	QUnit.test( "val() respects numbers without exception (Bug #9319)", function( assert ) {
+	assert.expect( 2 );
 
-		assert.expect( 4 );
+	var $progress = jQuery( "<progress max='10' value='1.5'></progress>" );
-
-		var $meter = jQuery( "<meter min='0' max='10' value='5.6'></meter>" ),
-			$progress = jQuery( "<progress max='10' value='1.5'></progress>" );
 
 	try {
-			assert.equal( typeof $meter.val(), "number", "meter, returns a number and does not throw exception" );
-			assert.equal( $meter.val(), $meter[ 0 ].value, "meter, api matches host and does not throw exception" );
-
 		assert.equal( typeof $progress.val(), "number", "progress, returns a number and does not throw exception" );
 		assert.equal( $progress.val(), $progress[ 0 ].value, "progress, api matches host and does not throw exception" );
 
 	} catch ( e ) {}
 
-		$meter.remove();
 	$progress.remove();
-	} );
+} );
-}
+
+// IE doesn't support <meter>
+QUnit.testUnlessIE( "val() respects numbers without exception (Bug #9319) - meter",
+	function( assert ) {
+
+	assert.expect( 2 );
+
+	var $meter = jQuery( "<meter min='0' max='10' value='5.6'></meter>" );
+
+	try {
+		assert.equal( typeof $meter.val(), "number", "meter, returns a number and does not throw exception" );
+		assert.equal( $meter.val(), $meter[ 0 ].value, "meter, api matches host and does not throw exception" );
+	} catch ( e ) {}
+
+	$meter.remove();
+} );
 
 var testVal = function( valueObj, assert ) {
 	assert.expect( 9 );

test/unit/core.js

@@ -329,7 +329,7 @@ QUnit.test( "isPlainObject", function( assert ) {
 	}
 } );
 
-QUnit[ typeof Symbol === "function" ? "test" : "skip" ]( "isPlainObject(Symbol)", function( assert ) {
+QUnit.testUnlessIE( "isPlainObject(Symbol)", function( assert ) {
 	assert.expect( 2 );
 
 	assert.equal( jQuery.isPlainObject( Symbol() ), false, "Symbol" );
@@ -342,7 +342,7 @@ QUnit.test( "isPlainObject(localStorage)", function( assert ) {
 	assert.equal( jQuery.isPlainObject( localStorage ), false );
 } );
 
-QUnit[ "assign" in Object ? "test" : "skip" ]( "isPlainObject(Object.assign(...))",
+QUnit.testUnlessIE( "isPlainObject(Object.assign(...))",
 	function( assert ) {
 		assert.expect( 1 );
 

test/unit/css.js

@@ -641,7 +641,11 @@ QUnit.test( "show/hide detached nodes", function( assert ) {
 	span.remove();
 } );
 
-QUnit[ document.body.getRootNode ? "test" : "skip" ]( "show/hide shadow child nodes", function( assert ) {
+// Support: IE 11+, Edge 12 - 18+
+// IE/Edge don't support Shadow DOM.
+QUnit[ document.body.getRootNode ? "test" : "skip" ](
+	"show/hide shadow child nodes", function( assert ) {
+
 	assert.expect( 28 );
 	jQuery( "<div id='shadowHost'></div>" ).appendTo( "#qunit-fixture" );
 	var shadowHost = document.querySelector( "#shadowHost" );
@@ -1210,11 +1214,10 @@ QUnit.test( "Do not append px (#9548, #12990, #2792)", function( assert ) {
 } );
 
 
-QUnit[
+// IE doesn't support the standard version of CSS Grid.
-	jQuery( "<div/>" )[ 0 ].style.gridArea === "" ?
+QUnit.testUnlessIE( "Do not append px to CSS Grid-related properties (gh-4007)",
-	"test" :
+	function( assert ) {
-	"skip"
+
-]( "Do not append px to CSS Grid-related properties (gh-4007)", function( assert ) {
 	assert.expect( 12 );
 
 	var prop, value, subProp, subValue, $div,
@@ -1365,22 +1368,7 @@ testIframe(
 	}
 );
 
-( function() {
+QUnit.testUnlessIE( "css('width') and css('height') should return fractional values for nodes in the document", function( assert ) {
-	var supportsFractionalGBCR,
-		qunitFixture = document.getElementById( "qunit-fixture" ),
-		div = document.createElement( "div" );
-	div.style.width = "3.3px";
-	qunitFixture.appendChild( div );
-	supportsFractionalGBCR = div.getBoundingClientRect().width.toFixed( 1 ) === "3.3";
-	qunitFixture.removeChild( div );
-
-	QUnit.test( "css('width') and css('height') should return fractional values for nodes in the document", function( assert ) {
-		if ( !supportsFractionalGBCR ) {
-			assert.expect( 1 );
-			assert.ok( true, "This browser doesn't support fractional values in getBoundingClientRect()" );
-			return;
-		}
-
 	assert.expect( 2 );
 
 	var el = jQuery( "<div class='test-div'></div>" ).appendTo( "#qunit-fixture" );
@@ -1390,15 +1378,9 @@ testIframe(
 		"css('width') should return fractional values" );
 	assert.equal( Number( el.css( "height" ).replace( /px$/, "" ) ).toFixed( 1 ), "88.8",
 		"css('height') should return fractional values" );
-	} );
+} );
-
-	QUnit.test( "css('width') and css('height') should return fractional values for disconnected nodes", function( assert ) {
-		if ( !supportsFractionalGBCR ) {
-			assert.expect( 1 );
-			assert.ok( true, "This browser doesn't support fractional values in getBoundingClientRect()" );
-			return;
-		}
 
+QUnit.testUnlessIE( "css('width') and css('height') should return fractional values for disconnected nodes", function( assert ) {
 	assert.expect( 2 );
 
 	var el = jQuery( "<div style='width: 33.3px; height: 88.8px;'></div>" );
@@ -1407,8 +1389,7 @@ testIframe(
 		"css('width') should return fractional values" );
 	assert.equal( Number( el.css( "height" ).replace( /px$/, "" ) ).toFixed( 1 ), "88.8",
 		"css('height') should return fractional values" );
-	} );
+} );
-} )();
 
 QUnit.test( "certain css values of 'normal' should be convertable to a number, see #8627", function( assert ) {
 	assert.expect( 3 );
@@ -1736,16 +1717,9 @@ QUnit.test( "Do not throw on frame elements from css method (#15098)", function(
 
 } )();
 
-( function() {
+// IE doesn't support CSS variables.
-	var supportsCssVars,
+QUnit.testUnlessIE( "css(--customProperty)", function( assert ) {
-		elem = jQuery( "<div>" ).appendTo( document.body ),
-		div = elem[ 0 ];
 
-	div.style.setProperty( "--prop", "value" );
-	supportsCssVars = !!getComputedStyle( div ).getPropertyValue( "--prop" );
-	elem.remove();
-
-	QUnit[ supportsCssVars ? "test" : "skip" ]( "css(--customProperty)", function( assert ) {
 	jQuery( "#qunit-fixture" ).append(
 		"<style>\n" +
 		"    .test__customProperties {\n" +
@@ -1802,9 +1776,11 @@ QUnit.test( "Do not throw on frame elements from css method (#15098)", function(
 		assert.equal( $elem.css( "--prop4" ), "\"val4\"", "Works with double quotes" );
 		assert.equal( $elem.css( "--prop5" ), "'val5'", "Works with single quotes" );
 	}
-	} );
+} );
+
+// IE doesn't support CSS variables.
+QUnit.testUnlessIE( "Don't append px to CSS vars", function( assert ) {
 
-	QUnit[ supportsCssVars ? "test" : "skip" ]( "Don't append px to CSS vars", function( assert ) {
 	assert.expect( 3 );
 
 	var $div = jQuery( "<div>" ).appendTo( "#qunit-fixture" );
@@ -1817,13 +1793,11 @@ QUnit.test( "Do not throw on frame elements from css method (#15098)", function(
 	assert.equal( $div.css( "--a" ), "3", "--a: 3" );
 	assert.equal( $div.css( "--line-height" ), "4", "--line-height: 4" );
 	assert.equal( $div.css( "--lineHeight" ), "5", "--lineHeight: 5" );
-	} );
+} );
-} )();
-
-}
 
 // Support: IE 11+
-if ( document.documentMode ) {
+// This test requires Grid to be *not supported* to work.
+if ( QUnit.isIE ) {
 	// Make sure explicitly provided IE vendor prefix (`-ms-`) is not converted
 	// to a non-working `Ms` prefix in JavaScript.
 	QUnit.test( "IE vendor prefixes are not mangled", function( assert ) {
@@ -1836,3 +1810,5 @@ if ( document.documentMode ) {
 		assert.strictEqual( div.css( "-ms-grid-row" ), "1", "IE vendor prefixing" );
 	} );
 }
+
+}

test/unit/data.js

@@ -513,16 +513,14 @@ QUnit.test( ".removeData()", function( assert ) {
 	assert.equal( div.data( "test.foo" ), undefined, "Make sure data is intact" );
 } );
 
-if ( window.JSON && window.JSON.stringify ) {
+QUnit.test( "JSON serialization (#8108)", function( assert ) {
-	QUnit.test( "JSON serialization (#8108)", function( assert ) {
 	assert.expect( 1 );
 
 	var obj = { "foo": "bar" };
 	jQuery.data( obj, "hidden", true );
 
 	assert.equal( JSON.stringify( obj ), "{\"foo\":\"bar\"}", "Expando is hidden from JSON.stringify" );
-	} );
+} );
-}
 
 QUnit.test( ".data should follow html5 specification regarding camel casing", function( assert ) {
 	assert.expect( 12 );

test/unit/deferred.js

@@ -543,8 +543,7 @@ QUnit.test( "jQuery.Deferred.then - spec compatibility", function( assert ) {
 	} catch ( _ ) {}
 } );
 
-QUnit[ typeof Symbol === "function" && Symbol.toStringTag ? "test" : "skip" ](
+QUnit.testUnlessIE( "jQuery.Deferred.then - IsCallable determination (gh-3596)",
-	"jQuery.Deferred.then - IsCallable determination (gh-3596)",
 	function( assert ) {
 
 	assert.expect( 1 );
@@ -560,8 +559,7 @@ QUnit[ typeof Symbol === "function" && Symbol.toStringTag ? "test" : "skip" ](
 	defer.then( faker ).then( done );
 
 	defer.resolve();
-	}
+} );
-);
 
 QUnit.test( "jQuery.Deferred.exceptionHook", function( assert ) {
 

test/unit/deprecated.js

@@ -41,8 +41,7 @@ QUnit.test( "delegate/undelegate", function( assert ) {
 		.remove();
 } );
 
-if ( jQuery.fn.hover ) {
+QUnit[ jQuery.fn.hover ? "test" : "skip" ]( "hover() mouseenter mouseleave", function( assert ) {
-	QUnit.test( "hover() mouseenter mouseleave", function( assert ) {
 	assert.expect( 1 );
 
 	var times = 0,
@@ -60,10 +59,7 @@ if ( jQuery.fn.hover ) {
 		.mouseenter().mouseleave();
 
 	assert.equal( times, 4, "hover handlers fired" );
-
+} );
-	} );
-}
-
 
 QUnit[ jQuery.fn.click ? "test" : "skip" ]( "trigger() shortcuts", function( assert ) {
 	assert.expect( 5 );

test/unit/dimensions.js

@@ -659,9 +659,9 @@ QUnit.test( "interaction with scrollbars (gh-3589)", function( assert ) {
 		parent = jQuery( "<div/>" )
 			.css( { position: "absolute", width: "1000px", height: "1000px" } )
 			.appendTo( "#qunit-fixture" ),
-		fraction = jQuery.support.boxSizingReliable() ?
+
-			jQuery( "<div style='width:4.5px;'/>" ).appendTo( parent ).width() % 1 :
+		// Workarounds for IE kill fractional output here.
-			0,
+		fraction = document.documentMode ? 0 : 0.5,
 		borderWidth = 1,
 		padding = 2,
 		size = 100 + fraction,

test/unit/effects.js

@@ -221,6 +221,8 @@ supportjQuery.each( hideOptions, function( type, setup ) {
 		assert.expectJqData( this, $span, "olddisplay" );
 	} );
 
+	// Support: IE 11+, Edge 12 - 18+
+	// IE/Edge don't support Shadow DOM.
 	QUnit[ document.body.getRootNode ? "test" : "skip" ](
 		"Persist correct display value - " + type + " hidden, shadow child", function( assert ) {
 		assert.expect( 3 );

test/unit/manipulation.js

@@ -445,8 +445,7 @@ QUnit.test( "append HTML5 sectioning elements (Bug #6485)", function( assert ) {
 	assert.equal( aside.length, 1, "HTML5 elements do not collapse their children" );
 } );
 
-if ( jQuery.css ) {
+QUnit[ jQuery.fn.css ? "test" : "skip" ]( "HTML5 Elements inherit styles from style rules (Bug #10501)", function( assert ) {
-	QUnit.test( "HTML5 Elements inherit styles from style rules (Bug #10501)", function( assert ) {
 
 	assert.expect( 1 );
 
@@ -455,8 +454,7 @@ if ( jQuery.css ) {
 
 	// In IE, the missing background color will claim its value is "transparent"
 	assert.notEqual( jQuery( "section" ).css( "background-color" ), "transparent", "HTML5 elements inherit styles" );
-	} );
+} );
-}
 
 QUnit.test( "html(String) with HTML5 (Bug #6485)", function( assert ) {
 
@@ -1767,9 +1765,9 @@ QUnit.test( "html(Function)", function( assert ) {
 QUnit[
 	// Support: Edge 16 - 18+
 	// Edge sometimes doesn't execute module scripts so skip the test there.
-	( QUnit.moduleTypeSupported && !/edge\//i.test( navigator.userAgent ) ) ?
+	( QUnit.isIE || /edge\//i.test( navigator.userAgent ) ) ?
-		"test" :
+		"skip" :
-		"skip"
+		"test"
 ]( "html(script type module)", function( assert ) {
 	assert.expect( 4 );
 	var done = assert.async(),
@@ -1794,18 +1792,17 @@ QUnit[
 
 QUnit.test( "html(script nomodule)", function( assert ) {
 
-	// Support: IE 9 - 11+
 	// `nomodule` scripts should be executed by legacy browsers only.
-	assert.expect( QUnit.moduleTypeSupported ? 0 : 4 );
+	assert.expect( QUnit.isIE ? 4 : 0 );
 	var done = assert.async(),
 		$fixture = jQuery( "#qunit-fixture" );
 
 	$fixture.html(
 		[
-			"<script nomodule>QUnit.assert.ok( !QUnit.moduleTypeSupported, 'evaluated: nomodule script' );</script>",
+			"<script nomodule>QUnit.assert.ok( QUnit.isIE, 'evaluated: nomodule script' );</script>",
 			"<script nomodule src='" + url( "nomodule.js" ) + "'></script>",
 			"<div>",
-				"<script nomodule>QUnit.assert.ok( !QUnit.moduleTypeSupported, 'evaluated: inner nomodule script' );</script>",
+				"<script nomodule>QUnit.assert.ok( QUnit.isIE, 'evaluated: inner nomodule script' );</script>",
 				"<script nomodule src='" + url( "inner_nomodule.js" ) + "'></script>",
 			"</div>"
 		].join( "" )

test/unit/queue.js

@@ -271,8 +271,7 @@ QUnit.test( ".promise(obj)", function( assert ) {
 	assert.strictEqual( promise, obj, ".promise(type, obj) returns obj" );
 } );
 
-if ( jQuery.fn.stop ) {
+QUnit[ jQuery.fn.stop ? "test" : "skip" ]( "delay() can be stopped", function( assert ) {
-	QUnit.test( "delay() can be stopped", function( assert ) {
 	var done = assert.async();
 	assert.expect( 3 );
 	var storage = {};
@@ -307,9 +306,9 @@ if ( jQuery.fn.stop ) {
 	setTimeout( function() {
 		done();
 	}, 1500 );
-	} );
+} );
 
-	QUnit.test( "queue stop hooks", function( assert ) {
+QUnit[ jQuery.fn.stop ? "test" : "skip" ]( "queue stop hooks", function( assert ) {
 	assert.expect( 2 );
 	var done = assert.async();
 	var foo = jQuery( "#foo" );
@@ -329,6 +328,4 @@ if ( jQuery.fn.stop ) {
 	} );
 
 	foo.stop( false, true );
-	} );
+} );
-
-} // if ( jQuery.fn.stop )

test/unit/support.js

@@ -58,48 +58,12 @@ testIframe(
 	var expected,
 		userAgent = window.navigator.userAgent,
 		expectedMap = {
-			edge: {
+			edge: {},
-				boxSizingReliable: true,
+			ie_11: {},
-				clearCloneStyle: true,
+			chrome: {},
-				noCloneChecked: true,
+			safari: {},
-				optSelected: true,
+			firefox: {},
-				radioValue: true
+			ios: {}
-			},
-			ie_11: {
-				boxSizingReliable: false,
-				clearCloneStyle: false,
-				noCloneChecked: false,
-				optSelected: false,
-				radioValue: false
-			},
-			chrome: {
-				boxSizingReliable: true,
-				clearCloneStyle: true,
-				noCloneChecked: true,
-				optSelected: true,
-				radioValue: true
-			},
-			safari: {
-				boxSizingReliable: true,
-				clearCloneStyle: true,
-				noCloneChecked: true,
-				optSelected: true,
-				radioValue: true
-			},
-			firefox: {
-				boxSizingReliable: true,
-				clearCloneStyle: true,
-				noCloneChecked: true,
-				optSelected: true,
-				radioValue: true
-			},
-			ios: {
-				boxSizingReliable: true,
-				clearCloneStyle: true,
-				noCloneChecked: true,
-				optSelected: true,
-				radioValue: true
-			}
 		};
 
 	if ( /edge\//i.test( userAgent ) ) {
@@ -140,8 +104,8 @@ testIframe(
 		}
 	} );
 
-	QUnit.test( "Verify most support tests are failing in one " +
+	QUnit.test( "Verify support tests are failing in one of tested browsers",
-		"of tested browsers", function( assert ) {
+		function( assert ) {
 
 		var prop, browserKey, supportTestName,
 			i = 0,

test/unit/traversing.js

@@ -773,7 +773,7 @@ QUnit.test( "contents() for <template />", function( assert ) {
 	assert.equal( contents.filter( "div" ).length, 3, "Count cloned elements from template" );
 } );
 
-QUnit[ "content" in document.createElement( "template" ) ? "test" : "skip" ]( "contents() for <template /> remains inert", function( assert ) {
+QUnit.testUnlessIE( "contents() for <template /> remains inert", function( assert ) {
 	assert.expect( 2 );
 
 	Globals.register( "testScript" );