Attributes: Make .attr( name, false ) remove for all non-ARIA attrs

mgol · gibson042 · web-flow · commit 063831b6378d · 2024-03-20T00:46:30.000+01:00
The HTML spec defines boolean attributes: https://html.spec.whatwg.org/#boolean-attributes that often correlate with boolean properties. If the attribute is missing, it correlates with the `false` property value, if it's present - the `true` property value. The only valid values are an empty string or the attribute name. jQuery tried to be helpful here and treated boolean attributes in a special way in the `.attr()` API: 1. For the getter, as long as the attribute was present, it was returning the attribute name lowercased, ignoring the value. 2. For the setter, it was removing the attribute when `false` was passed; otherwise, it was ignoring the passed value and set the attribute - interestingly, in jQuery `>=3` not lowercased anymore. The problem is the spec occasionally converts boolean attributes into ones with additional attribute values with special behavior - one such example is the new `"until-found"` value for the `hidden` attribute. Our setter normalization means passing those values is impossible with jQuery. Also, new boolean attributes are introduced occasionally and jQuery cannot easily add them to the list without incurring breaking changes. This patch removes any special handling of boolean attributes - the getter returns the value as-is and the setter sets the provided value. To provide better backwards compatibility with the very frequent `false` value provided to remove the attribute, this patch makes `false` trigger attribute removal for ALL non-ARIA attributes. ARIA attributes are exempt from the rule since many of them recognize `"false"` as a valid value with semantics different than the attribute missing. To remove an ARIA attribute, use `.removeAttr()` or pass `null` as the value to `.attr()` which doesn't have this exception. Fixes gh-5388 Closes gh-5452 Co-authored-by: Richard Gibson <richard.gibson@gmail.com>
diff --git a/src/attributes/attr.js b/src/attributes/attr.js
@@ -38,7 +38,14 @@ jQuery.extend( {
 		}
 
 		if ( value !== undefined ) {
-			if ( value === null ) {
+			if ( value === null ||
+
+				// For compat with previous handling of boolean attributes,
+				// remove when `false` passed. For ARIA attributes -
+				// many of which recognize a `"false"` value - continue to
+				// set the `"false"` value as jQuery <4 did.
+				( value === false && name.toLowerCase().indexOf( "aria-" ) !== 0 ) ) {
+
 				jQuery.removeAttr( elem, name );
 				return;
 			}
@@ -96,32 +103,3 @@ if ( isIE ) {
 		}
 	};
 }
-
-// HTML boolean attributes have special behavior:
-// we consider the lowercase name to be the only valid value, so
-// getting (if the attribute is present) normalizes to that, as does
-// setting to any non-`false` value (and setting to `false` removes the attribute).
-// See https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#boolean-attributes
-jQuery.each( (
-	"checked selected async autofocus autoplay controls defer disabled " +
-	"hidden ismap loop multiple open readonly required scoped"
-).split( " " ), function( _i, name ) {
-	jQuery.attrHooks[ name ] = {
-		get: function( elem ) {
-			return elem.getAttribute( name ) != null ?
-				name.toLowerCase() :
-				null;
-		},
-
-		set: function( elem, value, name ) {
-			if ( value === false ) {
-
-				// Remove boolean attributes when set to false
-				jQuery.removeAttr( elem, name );
-			} else {
-				elem.setAttribute( name, name );
-			}
-			return name;
-		}
-	};
-} );
diff --git a/test/unit/attributes.js b/test/unit/attributes.js
@@ -304,12 +304,12 @@ QUnit.test( "attr(String, Object)", function( assert ) {
 	assert.equal( $input[ 0 ].selected, true, "Setting selected updates property (verified by native property)" );
 
 	$input = jQuery( "#check2" );
-	$input.prop( "checked", true ).prop( "checked", false ).attr( "checked", true );
+	$input.prop( "checked", true ).prop( "checked", false ).attr( "checked", "checked" );
 	assert.equal( $input.attr( "checked" ), "checked", "Set checked (verified by .attr)" );
 	$input.prop( "checked", false ).prop( "checked", true ).attr( "checked", false );
 	assert.equal( $input.attr( "checked" ), undefined, "Remove checked (verified by .attr)" );
 
-	$input = jQuery( "#text1" ).prop( "readOnly", true ).prop( "readOnly", false ).attr( "readonly", true );
+	$input = jQuery( "#text1" ).prop( "readOnly", true ).prop( "readOnly", false ).attr( "readonly", "readonly" );
 	assert.equal( $input.attr( "readonly" ), "readonly", "Set readonly (verified by .attr)" );
 	$input.prop( "readOnly", false ).prop( "readOnly", true ).attr( "readonly", false );
 	assert.equal( $input.attr( "readonly" ), undefined, "Remove readonly (verified by .attr)" );
@@ -318,7 +318,7 @@ QUnit.test( "attr(String, Object)", function( assert ) {
 	assert.equal( $input[ 0 ].checked, true, "Set checked property (verified by native property)" );
 	assert.equal( $input.prop( "checked" ), true, "Set checked property (verified by .prop)" );
 	assert.equal( $input.attr( "checked" ), undefined, "Setting checked property doesn't affect checked attribute" );
-	$input.attr( "checked", false ).attr( "checked", true ).prop( "checked", false );
+	$input.attr( "checked", false ).attr( "checked", "checked" ).prop( "checked", false );
 	assert.equal( $input[ 0 ].checked, false, "Clear checked property (verified by native property)" );
 	assert.equal( $input.prop( "checked" ), false, "Clear checked property (verified by .prop)" );
 	assert.equal( $input.attr( "checked" ), "checked", "Clearing checked property doesn't affect checked attribute" );
@@ -345,22 +345,22 @@ QUnit.test( "attr(String, Object)", function( assert ) {
 
 	// HTML5 boolean attributes
 	$text = jQuery( "#text1" ).attr( {
-		"autofocus": true,
-		"required": true
+		"autofocus": "autofocus",
+		"required": "required"
 	} );
 	assert.equal( $text.attr( "autofocus" ), "autofocus", "Reading autofocus attribute yields 'autofocus'" );
 	assert.equal( $text.attr( "autofocus", false ).attr( "autofocus" ), undefined, "Setting autofocus to false removes it" );
 	assert.equal( $text.attr( "required" ), "required", "Reading required attribute yields 'required'" );
 	assert.equal( $text.attr( "required", false ).attr( "required" ), undefined, "Setting required attribute to false removes it" );
 
 	$details = jQuery( "<details open></details>" ).appendTo( "#qunit-fixture" );
-	assert.equal( $details.attr( "open" ), "open", "open attribute presence indicates true" );
+	assert.equal( $details.attr( "open" ), "", "open attribute presence indicates true" );
 	assert.equal( $details.attr( "open", false ).attr( "open" ), undefined, "Setting open attribute to false removes it" );
 
 	$text.attr( "data-something", true );
 	assert.equal( $text.attr( "data-something" ), "true", "Set data attributes" );
 	assert.equal( $text.data( "something" ), true, "Setting data attributes are not affected by boolean settings" );
-	$text.attr( "data-another", false );
+	$text.attr( "data-another", "false" );
 	assert.equal( $text.attr( "data-another" ), "false", "Set data attributes" );
 	assert.equal( $text.data( "another" ), false, "Setting data attributes are not affected by boolean settings" );
 	assert.equal( $text.attr( "aria-disabled", false ).attr( "aria-disabled" ), "false", "Setting aria attributes are not affected by boolean settings" );
@@ -1790,21 +1790,79 @@ QUnit.test( "non-lowercase boolean attribute getters should not crash", function
 
 	var elem = jQuery( "<input checked required autofocus type='checkbox'>" );
 
-	jQuery.each( {
-		checked: "Checked",
-		required: "requiRed",
-		autofocus: "AUTOFOCUS"
-	}, function( lowercased, original ) {
+	[
+		"Checked", "requiRed", "AUTOFOCUS"
+	].forEach( function( inconsistentlyCased ) {
 		try {
-			assert.strictEqual( elem.attr( original ), lowercased,
-				"The '" + this + "' attribute getter should return the lowercased name" );
+			assert.strictEqual( elem.attr( inconsistentlyCased ), "",
+				"The '" + this + "' attribute getter should return an empty string" );
 		} catch ( e ) {
 			assert.ok( false, "The '" + this + "' attribute getter threw" );
 		}
 	} );
 } );
 
 
+QUnit.test( "false setter removes non-ARIA attrs (gh-5388)", function( assert ) {
+	assert.expect( 24 );
+
+	var elem = jQuery( "<input" +
+		"	checked required autofocus" +
+		"	type='checkbox'" +
+		"	title='Example title'" +
+		"	class='test-class'" +
+		"	style='color: brown'" +
+		"	aria-hidden='true'" +
+		"	aria-checked='true'" +
+		"	aria-label='Example ARIA label'" +
+		"	data-prop='Example data value'" +
+		"	data-title='Example data title'" +
+		"	data-true='true'" +
+		">" );
+
+	function testFalseSetter( attributes, options ) {
+		var removal = options.removal;
+
+		attributes.forEach( function( attrName ) {
+			assert.ok( elem.attr( attrName ) != null,
+				"Attribute '" + attrName + "': initial defined value" );
+			elem.attr( attrName, false );
+
+			if ( removal ) {
+				assert.strictEqual( elem.attr( attrName ), undefined,
+					"Attribute '" + attrName + "' removed" );
+			} else {
+				assert.strictEqual( elem.attr( attrName ), "false",
+					"Attribute '" + attrName + "' set to 'false'" );
+			}
+		} );
+	}
+
+	// Boolean attributes
+	testFalseSetter(
+		[ "checked", "required", "autofocus" ],
+		{ removal: true }
+	);
+
+	// Regular attributes
+	testFalseSetter(
+		[ "title", "class", "style" ],
+		{ removal: true }
+	);
+
+	// `aria-*` attributes
+	testFalseSetter(
+		[ "aria-hidden", "aria-checked", "aria-label" ],
+		{ removal: false }
+	);
+
+	// `data-*` attributes
+	testFalseSetter(
+		[ "data-prop", "data-title", "data-true" ],
+		{ removal: true }
+	);
+} );
+
 // Test trustedTypes support in browsers where they're supported (currently Chrome 83+).
 // Browsers with no TrustedScriptURL support still run tests on object wrappers with
 // a proper `toString` function.
diff --git a/test/unit/selector.js b/test/unit/selector.js
@@ -948,10 +948,10 @@ QUnit.test( "pseudo - nth-last-of-type", function( assert ) {
 QUnit[ QUnit.jQuerySelectors ? "test" : "skip" ]( "pseudo - has", function( assert ) {
 	assert.expect( 4 );
 
-	assert.t( "Basic test", "p:has(a)", [ "firstp", "ap", "en", "sap" ] );
-	assert.t( "Basic test (irrelevant whitespace)", "p:has( a )", [ "firstp", "ap", "en", "sap" ] );
-	assert.t( "Nested with overlapping candidates",
-		"#qunit-fixture div:has(div:has(div:not([id])))",
+	assert.selectInFixture( "Basic test", "p:has(a)", [ "firstp", "ap", "en", "sap" ] );
+	assert.selectInFixture( "Basic test (irrelevant whitespace)", "p:has( a )", [ "firstp", "ap", "en", "sap" ] );
+	assert.selectInFixture( "Nested with overlapping candidates",
+		"div:has(div:has(div:not([id])))",
 		[ "moretests", "t2037", "fx-test-group", "fx-queue" ] );
 
 	// Support: Safari 15.4+, Chrome 105+
