Events: don't execute native stop(Immediate)Propagation from simulation

In Firefox, called `stop(Immediate)Propagation` methods,
in capturing phase prevents receiving focus

Fixes gh-3111

src/event.js

@@ -558,13 +558,14 @@ jQuery.Event.prototype = {
 	isDefaultPrevented: returnFalse,
 	isPropagationStopped: returnFalse,
 	isImmediatePropagationStopped: returnFalse,
+	isSimulated: false,
 
 	preventDefault: function() {
 		var e = this.originalEvent;
 
 		this.isDefaultPrevented = returnTrue;
 
-		if ( e ) {
+		if ( e && !this.isSimulated ) {
 			e.preventDefault();
 		}
 	},
@@ -573,7 +574,7 @@ jQuery.Event.prototype = {
 
 		this.isPropagationStopped = returnTrue;
 
-		if ( e ) {
+		if ( e && !this.isSimulated ) {
 			e.stopPropagation();
 		}
 	},
@@ -582,7 +583,7 @@ jQuery.Event.prototype = {
 
 		this.isImmediatePropagationStopped = returnTrue;
 
-		if ( e ) {
+		if ( e && !this.isSimulated ) {
 			e.stopImmediatePropagation();
 		}
 

src/event/trigger.js

@@ -150,6 +150,7 @@ jQuery.extend( jQuery.event, {
 	},
 
 	// Piggyback on a donor event to simulate a different one
+	// Used only for `focus(in | out)` events
 	simulate: function( type, elem, event ) {
 		var e = jQuery.extend(
 			new jQuery.Event(),
@@ -157,27 +158,10 @@ jQuery.extend( jQuery.event, {
 			{
 				type: type,
 				isSimulated: true
-
-				// Previously, `originalEvent: {}` was set here, so stopPropagation call
-				// would not be triggered on donor event, since in our own
-				// jQuery.event.stopPropagation function we had a check for existence of
-				// originalEvent.stopPropagation method, so, consequently it would be a noop.
-				//
-				// But now, this "simulate" function is used only for events
-				// for which stopPropagation() is noop, so there is no need for that anymore.
-				//
-				// For the compat branch though, guard for "click" and "submit"
-				// events is still used, but was moved to jQuery.event.stopPropagation function
-				// because `originalEvent` should point to the original event for the constancy
-				// with other events and for more focused logic
 			}
 		);
 
 		jQuery.event.trigger( e, null, elem );
-
-		if ( e.isDefaultPrevented() ) {
-			event.preventDefault();
-		}
 	}
 
 } );

test/unit/event.js

@@ -2790,6 +2790,81 @@ QUnit.test( "Donor event interference", function( assert ) {
 	jQuery( "#donor-input" )[ 0 ].click();
 } );
 
+QUnit.test(
+	"native stop(Immediate)Propagation/preventDefault methods shouldn't be called",
+	function( assert ) {
+		var userAgent = window.navigator.userAgent;
+
+		if ( !( /firefox/i.test( userAgent ) || /safari/i.test( userAgent ) ) ) {
+			assert.expect( 1 );
+			assert.ok( true, "Assertions should run only in Chrome, Safari, Fx & Edge" );
+			return;
+		}
+
+		assert.expect( 3 );
+
+		var checker = {};
+
+		var html = "<div id='donor-outer'>" +
+			"<form id='donor-form'>" +
+				"<input id='donor-input' type='radio' />" +
+			"</form>" +
+		"</div>";
+
+		jQuery( "#qunit-fixture" ).append( html );
+		var outer = jQuery( "#donor-outer" );
+
+		outer
+			.on( "focusin", function( event ) {
+				checker.prevent = sinon.stub( event.originalEvent, "preventDefault" );
+				event.preventDefault();
+			} )
+			.on( "focusin", function( event ) {
+				checker.simple = sinon.stub( event.originalEvent, "stopPropagation" );
+				event.stopPropagation();
+			} )
+			.on( "focusin", function( event ) {
+				checker.immediate = sinon.stub( event.originalEvent, "stopImmediatePropagation" );
+				event.stopImmediatePropagation();
+			} );
+
+		jQuery( "#donor-input" ).trigger( "focus" );
+		assert.strictEqual( checker.simple.called, false );
+		assert.strictEqual( checker.immediate.called, false );
+		assert.strictEqual( checker.prevent.called, false );
+
+		// We need to "off" it, since yes QUnit always update the fixtures
+		// but "focus" event listener is attached to document for focus(in | out)
+		// event and document doesn't get cleared obviously :)
+		outer.off( "focusin" );
+	}
+);
+
+QUnit.test(
+	"isSimulated property always exist on event object",
+	function( assert ) {
+		var userAgent = window.navigator.userAgent;
+
+		if ( !( /firefox/i.test( userAgent ) || /safari/i.test( userAgent ) ) ) {
+			assert.expect( 1 );
+			assert.ok( true, "Assertions should run only in Chrome, Safari, Fx & Edge" );
+			return;
+		}
+
+		assert.expect( 1 );
+
+		var element = jQuery( "<input/>" );
+
+		jQuery( "#qunit-fixture" ).append( element );
+
+		element.on( "focus", function( event ) {
+			assert.notOk( event.isSimulated );
+		} );
+
+		element.trigger( "focus" );
+	}
+);
+
 QUnit.test( "originalEvent property for Chrome, Safari, Fx & Edge of simulated event", function( assert ) {
 	var userAgent = window.navigator.userAgent;
 
@@ -2800,6 +2875,7 @@ QUnit.test( "originalEvent property for Chrome, Safari, Fx & Edge of simulated e
 	}
 
 	assert.expect( 4 );
+	var done = assert.async();
 
 	var html = "<div id='donor-outer'>" +
 		"<form id='donor-form'>" +
@@ -2808,19 +2884,26 @@ QUnit.test( "originalEvent property for Chrome, Safari, Fx & Edge of simulated e
 	"</div>";
 
 	jQuery( "#qunit-fixture" ).append( html );
+	var outer = jQuery( "#donor-outer" );
 
-	jQuery( "#donor-outer" ).on( "focusin", function( event ) {
-		assert.ok( true, "focusin bubbled to outer div" );
-		assert.equal( event.originalEvent.type, "focus",
-		             "make sure originalEvent type is correct" );
-		assert.equal( event.type, "focusin", "make sure type is correct" );
-	} );
+	outer
+		.on( "focusin", function( event ) {
+			assert.ok( true, "focusin bubbled to outer div" );
+			assert.equal( event.originalEvent.type, "focus",
+			             "make sure originalEvent type is correct" );
+			assert.equal( event.type, "focusin", "make sure type is correct" );
+		} );
 	jQuery( "#donor-input" ).on( "focus", function() {
 		assert.ok( true, "got a focus event from the input" );
+		done();
 	} );
 	jQuery( "#donor-input" ).trigger( "focus" );
-} );
 
+	// We need to "off" it, since yes QUnit always update the fixtures
+	// but "focus" event listener is attached to document for focus(in | out)
+	// event and document doesn't get cleared obviously :)
+	outer.off( "focusin" );
+} );
 
 QUnit[ jQuery.fn.click ? "test" : "skip" ]( "trigger() shortcuts", function( assert ) {
 	assert.expect( 5 );