Effects: set default easing using jQuery.easing._default

Fixes gh-2219
Close gh-2218

src/effects.js

@@ -286,7 +286,10 @@ function Animation( elem, properties, options ) {
 		animation = deferred.promise({
 			elem: elem,
 			props: jQuery.extend( {}, properties ),
-			opts: jQuery.extend( true, { specialEasing: {} }, options ),
+			opts: jQuery.extend( true, {
+				specialEasing: {},
+				easing: jQuery.easing._default
+			}, options ),
 			originalProperties: properties,
 			originalOptions: options,
 			startTime: fxNow || createFxNow(),

src/effects/Tween.js

@@ -13,7 +13,7 @@ Tween.prototype = {
 	init: function( elem, options, prop, end, easing, unit ) {
 		this.elem = elem;
 		this.prop = prop;
-		this.easing = easing || "swing";
+		this.easing = easing || jQuery.easing._default;
 		this.options = options;
 		this.start = this.now = this.cur();
 		this.end = end;
@@ -105,7 +105,8 @@ jQuery.easing = {
 	},
 	swing: function( p ) {
 		return 0.5 - Math.cos( p * Math.PI ) / 2;
-	}
+	},
+	_default: "swing"
 };
 
 jQuery.fx = Tween.prototype.init;

test/unit/effects.js

@@ -1191,45 +1191,45 @@ test("animate with per-property easing", function(){
 test("animate with CSS shorthand properties", function(){
 	expect(11);
 
-	var _default_count = 0,
+	var easeAnimation_count = 0,
-		_special_count = 0,
+		easeProperty_count = 0,
 		propsBasic = { "padding": "10 20 30" },
-		propsSpecial = { "padding": [ "1 2 3", "_special" ] };
+		propsSpecial = { "padding": [ "1 2 3", "propertyScope" ] };
 
-	jQuery.easing._default = function(p) {
+	jQuery.easing.animationScope = function(p) {
 		if ( p >= 1 ) {
-			_default_count++;
+			easeAnimation_count++;
 		}
 		return p;
 	};
 
-	jQuery.easing._special = function(p) {
+	jQuery.easing.propertyScope = function(p) {
 		if ( p >= 1 ) {
-			_special_count++;
+			easeProperty_count++;
 		}
 		return p;
 	};
 
 	jQuery("#foo")
-		.animate( propsBasic, 200, "_default", function() {
+		.animate( propsBasic, 200, "animationScope", function() {
 			equal( this.style.paddingTop, "10px", "padding-top was animated" );
 			equal( this.style.paddingLeft, "20px", "padding-left was animated" );
 			equal( this.style.paddingRight, "20px", "padding-right was animated" );
 			equal( this.style.paddingBottom, "30px", "padding-bottom was animated" );
-			equal( _default_count, 4, "per-animation default easing called for each property" );
+			equal( easeAnimation_count, 4, "per-animation default easing called for each property" );
-			_default_count = 0;
+			easeAnimation_count = 0;
 		})
-		.animate( propsSpecial, 200, "_default", function() {
+		.animate( propsSpecial, 200, "animationScope", function() {
 			equal( this.style.paddingTop, "1px", "padding-top was animated again" );
 			equal( this.style.paddingLeft, "2px", "padding-left was animated again" );
 			equal( this.style.paddingRight, "2px", "padding-right was animated again" );
 			equal( this.style.paddingBottom, "3px", "padding-bottom was animated again" );
-			equal( _default_count, 0, "per-animation default easing not called" );
+			equal( easeAnimation_count, 0, "per-animation default easing not called" );
-			equal( _special_count, 4, "special easing called for each property" );
+			equal( easeProperty_count, 4, "special easing called for each property" );
 
 			jQuery(this).css("padding", "0");
-			delete jQuery.easing._default;
+			delete jQuery.easing.animationScope;
-			delete jQuery.easing._special;
+			delete jQuery.easing.propertyScope;
 		});
 		this.clock.tick( 400 );
 });
@@ -2227,5 +2227,25 @@ test( "Animation should go to its end state if document.hidden = true", 1, funct
 	}
 });
 
+test( "jQuery.easing._default (#2218)", 2, function() {
+	jQuery( "#foo" )
+		.animate({ width: "5px" }, {
+			duration: 5,
+			start: function( anim ) {
+				equal( anim.opts.easing, jQuery.easing._default,
+					"anim.opts.easing should be equal to jQuery.easing._default when the easing argument is not given" );
+			}
+		})
+		.animate({ height: "5px" }, {
+			duration: 5,
+			easing: "linear",
+			start: function( anim ) {
+				equal( anim.opts.easing, "linear",
+					"anim.opts.easing should be equal to the easing argument" );
+			}
+		})
+		.stop();
+	this.clock.tick( 25 );
+});
 
 })();