Added setup function which can supply static methods/properties. Closes #480. Closes #578.

src/generators/dom/index.ts

@@ -275,6 +275,8 @@ export default function dom(
 			this._state = {};
 			this._destroyed = true;
 		};
+
+		${templateProperties.setup && `@template.setup.call( ${name} );`}
 	`);
 
 	const usedHelpers = new Set();

src/validate/js/propValidators/index.ts

@@ -10,6 +10,7 @@ import components from './components';
 import events from './events';
 import namespace from './namespace';
 import transitions from './transitions';
+import setup from './setup';
 
 export default {
 	data,
@@ -24,4 +25,5 @@ export default {
 	events,
 	namespace,
 	transitions,
+	setup,
 };

src/validate/js/propValidators/setup.ts

@@ -0,0 +1,14 @@
+import usesThisOrArguments from '../utils/usesThisOrArguments';
+import { Validator } from '../../';
+import { Node } from '../../../interfaces';
+
+export default function setup(validator: Validator, prop: Node) {
+	if (prop.value.type === 'ArrowFunctionExpression') {
+		if (usesThisOrArguments(prop.value.body)) {
+			validator.error(
+				`'setup' should be a function expression, not an arrow function expression`,
+				prop.start
+			);
+		}
+	}
+}

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

@@ -0,0 +1,188 @@
+function noop() {}
+
+function assign(target) {
+	var k,
+		source,
+		i = 1,
+		len = arguments.length;
+	for (; i < len; i++) {
+		source = arguments[i];
+		for (k in source) target[k] = source[k];
+	}
+
+	return target;
+}
+
+function differs(a, b) {
+	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+}
+
+function dispatchObservers(component, group, newState, oldState) {
+	for (var key in group) {
+		if (!(key in newState)) continue;
+
+		var newValue = newState[key];
+		var oldValue = oldState[key];
+
+		if (differs(newValue, oldValue)) {
+			var callbacks = group[key];
+			if (!callbacks) continue;
+
+			for (var i = 0; i < callbacks.length; i += 1) {
+				var callback = callbacks[i];
+				if (callback.__calling) continue;
+
+				callback.__calling = true;
+				callback.call(component, newValue, oldValue);
+				callback.__calling = false;
+			}
+		}
+	}
+}
+
+function get(key) {
+	return key ? this._state[key] : this._state;
+}
+
+function fire(eventName, data) {
+	var handlers =
+		eventName in this._handlers && this._handlers[eventName].slice();
+	if (!handlers) return;
+
+	for (var i = 0; i < handlers.length; i += 1) {
+		handlers[i].call(this, data);
+	}
+}
+
+function observe(key, callback, options) {
+	var group = options && options.defer
+		? this._observers.post
+		: this._observers.pre;
+
+	(group[key] || (group[key] = [])).push(callback);
+
+	if (!options || options.init !== false) {
+		callback.__calling = true;
+		callback.call(this, this._state[key]);
+		callback.__calling = false;
+	}
+
+	return {
+		cancel: function() {
+			var index = group[key].indexOf(callback);
+			if (~index) group[key].splice(index, 1);
+		}
+	};
+}
+
+function on(eventName, handler) {
+	if (eventName === 'teardown') return this.on('destroy', handler);
+
+	var handlers = this._handlers[eventName] || (this._handlers[eventName] = []);
+	handlers.push(handler);
+
+	return {
+		cancel: function() {
+			var index = handlers.indexOf(handler);
+			if (~index) handlers.splice(index, 1);
+		}
+	};
+}
+
+function set(newState) {
+	this._set(assign({}, newState));
+	if (this._root._lock) return;
+	this._root._lock = true;
+	callAll(this._root._beforecreate);
+	callAll(this._root._oncreate);
+	callAll(this._root._aftercreate);
+	this._root._lock = false;
+}
+
+function callAll(fns) {
+	while (fns && fns.length) fns.pop()();
+}
+
+var proto = {
+	get: get,
+	fire: fire,
+	observe: observe,
+	on: on,
+	set: set
+};
+
+var template = (function () {
+	return {
+		methods: {
+			foo ( bar ) {
+				console.log( bar );
+			}
+		},
+		setup () {
+			this.SOME_CONSTANT = 42;
+			this.prototype.foo( 'baz' );
+		}
+	};
+}());
+
+function create_main_fragment ( state, component ) {
+
+	return {
+		create: noop,
+
+		mount: noop,
+
+		unmount: noop,
+
+		destroy: noop
+	};
+}
+
+function SvelteComponent ( options ) {
+	options = options || {};
+	this._state = options.data || {};
+
+	this._observers = {
+		pre: Object.create( null ),
+		post: Object.create( null )
+	};
+
+	this._handlers = Object.create( null );
+
+	this._root = options._root || this;
+	this._yield = options._yield;
+
+	this._destroyed = false;
+
+	this._fragment = create_main_fragment( this._state, this );
+
+	if ( options.target ) {
+		this._fragment.create();
+		this._fragment.mount( options.target, null );
+	}
+}
+
+assign( SvelteComponent.prototype, template.methods, proto );
+
+SvelteComponent.prototype._set = function _set ( newState ) {
+	var oldState = this._state;
+	this._state = assign( {}, oldState, newState );
+	dispatchObservers( this, this._observers.pre, newState, oldState );
+	dispatchObservers( this, this._observers.post, newState, oldState );
+};
+
+SvelteComponent.prototype.teardown = SvelteComponent.prototype.destroy = function destroy ( detach ) {
+	if ( this._destroyed ) return;
+	this.fire( 'destroy' );
+
+	if ( detach !== false ) this._fragment.unmount();
+	this._fragment.destroy();
+	this._fragment = null;
+
+	this._state = {};
+	this._destroyed = true;
+};
+
+template.setup.call( SvelteComponent );
+
+export default SvelteComponent;

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

@@ -0,0 +1,77 @@
+import { assign, dispatchObservers, noop, proto } from "svelte/shared.js";
+
+var template = (function () {
+	return {
+		methods: {
+			foo ( bar ) {
+				console.log( bar );
+			}
+		},
+		setup () {
+			this.SOME_CONSTANT = 42;
+			this.prototype.foo( 'baz' );
+		}
+	};
+}());
+
+function create_main_fragment ( state, component ) {
+
+	return {
+		create: noop,
+
+		mount: noop,
+
+		unmount: noop,
+
+		destroy: noop
+	};
+}
+
+function SvelteComponent ( options ) {
+	options = options || {};
+	this._state = options.data || {};
+
+	this._observers = {
+		pre: Object.create( null ),
+		post: Object.create( null )
+	};
+
+	this._handlers = Object.create( null );
+
+	this._root = options._root || this;
+	this._yield = options._yield;
+
+	this._destroyed = false;
+
+	this._fragment = create_main_fragment( this._state, this );
+
+	if ( options.target ) {
+		this._fragment.create();
+		this._fragment.mount( options.target, null );
+	}
+}
+
+assign( SvelteComponent.prototype, template.methods, proto );
+
+SvelteComponent.prototype._set = function _set ( newState ) {
+	var oldState = this._state;
+	this._state = assign( {}, oldState, newState );
+	dispatchObservers( this, this._observers.pre, newState, oldState );
+	dispatchObservers( this, this._observers.post, newState, oldState );
+};
+
+SvelteComponent.prototype.teardown = SvelteComponent.prototype.destroy = function destroy ( detach ) {
+	if ( this._destroyed ) return;
+	this.fire( 'destroy' );
+
+	if ( detach !== false ) this._fragment.unmount();
+	this._fragment.destroy();
+	this._fragment = null;
+
+	this._state = {};
+	this._destroyed = true;
+};
+
+template.setup.call( SvelteComponent );
+
+export default SvelteComponent;

test/js/samples/setup-method/input.html

@@ -0,0 +1,13 @@
+<script>
+	export default {
+		methods: {
+			foo ( bar ) {
+				console.log( bar );
+			}
+		},
+		setup () {
+			this.SOME_CONSTANT = 42;
+			this.prototype.foo( 'baz' );
+		}
+	};
+</script>