Merge pull request #1282 from lukeed/fix/assign

Performance boost for Assign utility

src/generators/dom/index.ts

@@ -159,9 +159,9 @@ export default function dom(
 		? 'svelte/shared.js'
 		: options.shared || '';
 
-	const prototypeBase =
+	let prototypeBase = `${name}.prototype`;
-		`${name}.prototype` +
+	templateProperties.methods && (prototypeBase = `@assign(${prototypeBase}, %methods)`);
-		(templateProperties.methods ? `, %methods` : '');
+
 	const proto = sharedPath
 		? `@proto`
 		: deindent`
@@ -335,7 +335,7 @@ export default function dom(
 			}
 
 			customElements.define("${generator.tag}", ${name});
-			@assign(${prototypeBase}, ${proto}, {
+			@assign(@assign(${prototypeBase}, ${proto}), {
 				_mount(target, anchor) {
 					target.insertBefore(this, anchor);
 				},

src/generators/nodes/AwaitBlock.ts

@@ -125,7 +125,7 @@ export default class AwaitBlock extends Node {
 						${this.then.block.context ? deindent`
 							var state = #component.get();
 							${resolved} = { ${this.then.block.context}: ${value} };
-							${replace_await_block}(${token}, ${create_then_block}, @assign({}, state, ${resolved}));
+							${replace_await_block}(${token}, ${create_then_block}, @assign(@assign({}, state), ${resolved}));
 						` : deindent`
 							${replace_await_block}(${token}, null, null);
 						`}
@@ -133,7 +133,7 @@ export default class AwaitBlock extends Node {
 						${this.catch.block.context ? deindent`
 							var state = #component.get();
 							${resolved} = { ${this.catch.block.context}: ${error} };
-							${replace_await_block}(${token}, ${create_catch_block}, @assign({}, state, ${resolved}));
+							${replace_await_block}(${token}, ${create_catch_block}, @assign(@assign({}, state), ${resolved}));
 						` : deindent`
 							${replace_await_block}(${token}, null, null);
 						`}
@@ -147,7 +147,7 @@ export default class AwaitBlock extends Node {
 				} else {
 					${resolved} = { ${this.then.block.context}: ${promise} };
 					if (${await_block_type} !== ${create_then_block}) {
-						${replace_await_block}(${token}, ${create_then_block}, @assign({}, state, ${resolved}));
+						${replace_await_block}(${token}, ${create_then_block}, @assign(@assign({}, state), ${resolved}));
 						return true;
 					}
 				}
@@ -190,7 +190,7 @@ export default class AwaitBlock extends Node {
 				if (${conditions.join(' && ')}) {
 					// nothing
 				} else {
-					${await_block}.p(changed, @assign({}, state, ${resolved}));
+					${await_block}.p(changed, @assign(@assign({}, state), ${resolved}));
 				}
 			`);
 		} else {
@@ -217,4 +217,4 @@ export default class AwaitBlock extends Node {
 			});
 		});
 	}
-}
+}

src/generators/nodes/EachBlock.ts

@@ -267,7 +267,7 @@ export default class EachBlock extends Node {
 		block.builders.init.addBlock(deindent`
 			for (var #i = 0; #i < ${each_block_value}.${length}; #i += 1) {
 				var ${key} = ${each_block_value}[#i].${this.key};
-				${blocks}[#i] = ${lookup}[${key}] = ${create_each_block}(#component, ${key}, @assign({}, state, {
+				${blocks}[#i] = ${lookup}[${key}] = ${create_each_block}(#component, ${key}, @assign(@assign({}, state), {
 					${this.contextProps.join(',\n')}
 				}));
 			}
@@ -297,7 +297,7 @@ export default class EachBlock extends Node {
 			var ${each_block_value} = ${snippet};
 
 			${blocks} = @updateKeyedEach(${blocks}, #component, changed, "${this.key}", ${dynamic}, ${each_block_value}, ${lookup}, ${updateMountNode}, ${String(this.block.hasOutroMethod)}, ${create_each_block}, "${mountOrIntro}", function(#i) {
-				return @assign({}, state, {
+				return @assign(@assign({}, state), {
 					${this.contextProps.join(',\n')}
 				});
 			});
@@ -332,7 +332,7 @@ export default class EachBlock extends Node {
 			var ${iterations} = [];
 
 			for (var #i = 0; #i < ${each_block_value}.${length}; #i += 1) {
-				${iterations}[#i] = ${create_each_block}(#component, @assign({}, state, {
+				${iterations}[#i] = ${create_each_block}(#component, @assign(@assign({}, state), {
 					${this.contextProps.join(',\n')}
 				}));
 			}
@@ -430,7 +430,7 @@ export default class EachBlock extends Node {
 
 				if (${condition}) {
 					for (var #i = ${start}; #i < ${each_block_value}.${length}; #i += 1) {
-						var ${this.each_context} = @assign({}, state, {
+						var ${this.each_context} = @assign(@assign({}, state), {
 							${this.contextProps.join(',\n')}
 						});
 

src/shared/index.js

@@ -163,7 +163,7 @@ export function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

src/shared/utils.js

@@ -1,14 +1,6 @@
 export function noop() {}
 
-export function assign(target) {
+export function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }

store.js

@@ -133,7 +133,7 @@ assign(Store.prototype, {
 		}
 		if (!dirty) return;
 
-		this._state = assign({}, oldState, newState);
+		this._state = assign(assign({}, oldState), newState);
 
 		for (var i = 0; i < this._sortedComputedProperties.length; i += 1) {
 			this._sortedComputedProperties[i].update(this._state, changed);

test/js/samples/action/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -143,7 +135,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 
@@ -184,7 +176,7 @@ var proto = {
 /* generated by Svelte vX.Y.Z */
 
 function link(node) {
-  
+
   function onClick(event) {
     event.preventDefault();
     history.pushState(null, null, event.target.href);

test/js/samples/collapses-text-around-comments/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -151,7 +143,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/component-static-immutable/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -135,7 +127,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/component-static-immutable2/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -135,7 +127,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/component-static/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -131,7 +123,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/computed-collapsed-if/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -131,7 +123,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/css-media-query/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/css-shadow-dom-keyframes/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -143,7 +135,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 
@@ -234,7 +226,7 @@ class SvelteComponent extends HTMLElement {
 }
 
 customElements.define("custom-element", SvelteComponent);
-assign(SvelteComponent.prototype, proto, {
+assign(assign(SvelteComponent.prototype, proto), {
 	_mount(target, anchor) {
 		target.insertBefore(this, anchor);
 	},

test/js/samples/css-shadow-dom-keyframes/expected.js

@@ -52,7 +52,7 @@ class SvelteComponent extends HTMLElement {
 }
 
 customElements.define("custom-element", SvelteComponent);
-assign(SvelteComponent.prototype, proto, {
+assign(assign(SvelteComponent.prototype, proto), {
 	_mount(target, anchor) {
 		target.insertBefore(this, anchor);
 	},
@@ -61,4 +61,4 @@ assign(SvelteComponent.prototype, proto, {
 		this.parentNode.removeChild(this);
 	}
 });
-export default SvelteComponent;
+export default SvelteComponent;

test/js/samples/deconflict-builtins/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -161,7 +153,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 
@@ -209,7 +201,7 @@ function create_main_fragment(component, state) {
 	var each_blocks = [];
 
 	for (var i = 0; i < each_value.length; i += 1) {
-		each_blocks[i] = create_each_block(component, assign({}, state, {
+		each_blocks[i] = create_each_block(component, assign(assign({}, state), {
 			each_value: each_value,
 			node: each_value[i],
 			node_index: i
@@ -238,7 +230,7 @@ function create_main_fragment(component, state) {
 
 			if (changed.createElement) {
 				for (var i = 0; i < each_value.length; i += 1) {
-					var each_context = assign({}, state, {
+					var each_context = assign(assign({}, state), {
 						each_value: each_value,
 						node: each_value[i],
 						node_index: i

test/js/samples/deconflict-builtins/expected.js

@@ -9,7 +9,7 @@ function create_main_fragment(component, state) {
 	var each_blocks = [];
 
 	for (var i = 0; i < each_value.length; i += 1) {
-		each_blocks[i] = create_each_block(component, assign({}, state, {
+		each_blocks[i] = create_each_block(component, assign(assign({}, state), {
 			each_value: each_value,
 			node: each_value[i],
 			node_index: i
@@ -38,7 +38,7 @@ function create_main_fragment(component, state) {
 
 			if (changed.createElement) {
 				for (var i = 0; i < each_value.length; i += 1) {
-					var each_context = assign({}, state, {
+					var each_context = assign(assign({}, state), {
 						each_value: each_value,
 						node: each_value[i],
 						node_index: i
@@ -121,4 +121,4 @@ function SvelteComponent(options) {
 }
 
 assign(SvelteComponent.prototype, proto);
-export default SvelteComponent;
+export default SvelteComponent;

test/js/samples/deconflict-globals/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -131,7 +123,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/dev-warning-missing-data-computed/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -183,7 +175,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/do-use-dataset/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -151,7 +143,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/dont-use-dataset-in-svg/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -151,7 +143,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/each-block-changed-check/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -163,7 +155,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 
@@ -211,7 +203,7 @@ function create_main_fragment(component, state) {
 	var each_blocks = [];
 
 	for (var i = 0; i < each_value.length; i += 1) {
-		each_blocks[i] = create_each_block(component, assign({}, state, {
+		each_blocks[i] = create_each_block(component, assign(assign({}, state), {
 			each_value: each_value,
 			comment: each_value[i],
 			i: i
@@ -244,7 +236,7 @@ function create_main_fragment(component, state) {
 
 			if (changed.comments || changed.elapsed || changed.time) {
 				for (var i = 0; i < each_value.length; i += 1) {
-					var each_context = assign({}, state, {
+					var each_context = assign(assign({}, state), {
 						each_value: each_value,
 						comment: each_value[i],
 						i: i

test/js/samples/each-block-changed-check/expected.js

@@ -9,7 +9,7 @@ function create_main_fragment(component, state) {
 	var each_blocks = [];
 
 	for (var i = 0; i < each_value.length; i += 1) {
-		each_blocks[i] = create_each_block(component, assign({}, state, {
+		each_blocks[i] = create_each_block(component, assign(assign({}, state), {
 			each_value: each_value,
 			comment: each_value[i],
 			i: i
@@ -42,7 +42,7 @@ function create_main_fragment(component, state) {
 
 			if (changed.comments || changed.elapsed || changed.time) {
 				for (var i = 0; i < each_value.length; i += 1) {
-					var each_context = assign({}, state, {
+					var each_context = assign(assign({}, state), {
 						each_value: each_value,
 						comment: each_value[i],
 						i: i
@@ -166,4 +166,4 @@ function SvelteComponent(options) {
 }
 
 assign(SvelteComponent.prototype, proto);
-export default SvelteComponent;
+export default SvelteComponent;

test/js/samples/event-handlers-custom/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -143,7 +135,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 
@@ -237,6 +229,6 @@ function SvelteComponent(options) {
 	}
 }
 
-assign(SvelteComponent.prototype, methods, proto);
+assign(assign(SvelteComponent.prototype, methods), proto);
 
 export default SvelteComponent;

test/js/samples/event-handlers-custom/expected.js

@@ -56,5 +56,5 @@ function SvelteComponent(options) {
 	}
 }
 
-assign(SvelteComponent.prototype, methods, proto);
+assign(assign(SvelteComponent.prototype, methods), proto);
-export default SvelteComponent;
+export default SvelteComponent;

test/js/samples/head-no-whitespace/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -143,7 +135,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/if-block-no-update/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/if-block-simple/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/inline-style-optimized-multiple/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/inline-style-optimized-url/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/inline-style-optimized/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/inline-style-unoptimized/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -147,7 +139,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/input-without-blowback-guard/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -155,7 +147,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/legacy-default/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -165,7 +157,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/legacy-input-type/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -149,7 +141,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/legacy-quote-class/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -166,7 +158,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/media-bindings/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -159,7 +151,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/non-imported-component/expected-bundle.js

@@ -2,17 +2,9 @@ import Imported from 'Imported.html';
 
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function insertNode(node, target, anchor) {
@@ -145,7 +137,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/onrender-onteardown-rewritten/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -131,7 +123,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/setup-method/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -131,7 +123,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 
@@ -214,7 +206,7 @@ function SvelteComponent(options) {
 	}
 }
 
-assign(SvelteComponent.prototype, methods, proto);
+assign(assign(SvelteComponent.prototype, methods), proto);
 
 setup(SvelteComponent);
 

test/js/samples/setup-method/expected.js

@@ -44,7 +44,7 @@ function SvelteComponent(options) {
 	}
 }
 
-assign(SvelteComponent.prototype, methods, proto);
+assign(assign(SvelteComponent.prototype, methods), proto);
 
 setup(SvelteComponent);
-export default SvelteComponent;
+export default SvelteComponent;

test/js/samples/svg-title/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -151,7 +143,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/title/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function blankObject() {
@@ -131,7 +123,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/use-elements-as-anchors/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -155,7 +147,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);
 

test/js/samples/window-binding-scroll/expected-bundle.js

@@ -1,16 +1,8 @@
 function noop() {}
 
-function assign(target) {
+function assign(tar, src) {
-	var k,
+	for (var k in src) tar[k] = src[k];
-		source,
+	return tar;
-		i = 1,
-		len = arguments.length;
-	for (; i < len; i++) {
-		source = arguments[i];
-		for (k in source) target[k] = source[k];
-	}
-
-	return target;
 }
 
 function appendNode(node, target) {
@@ -151,7 +143,7 @@ function _set(newState) {
 	}
 	if (!dirty) return;
 
-	this._state = assign({}, oldState, newState);
+	this._state = assign(assign({}, oldState), newState);
 	this._recompute(changed, this._state);
 	if (this._bind) this._bind(changed, this._state);