svelte/shared.js

The magical disappearing UI framework

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 appendNode(node, target) {
	target.appendChild(node);
}

function insertNode(node, target, anchor) {
	target.insertBefore(node, anchor);
}

function detachNode(node) {
	node.parentNode.removeChild(node);
}

function detachBetween(before, after) {
	while (before.nextSibling && before.nextSibling !== after) {
		before.parentNode.removeChild(before.nextSibling);
	}
}

function detachBefore(after) {
	while (after.previousSibling) {
		after.parentNode.removeChild(after.previousSibling);
	}
}

function detachAfter(before) {
	while (before.nextSibling) {
		before.parentNode.removeChild(before.nextSibling);
	}
}

function reinsertBetween(before, after, target) {
	while (before.nextSibling && before.nextSibling !== after) {
		target.appendChild(before.parentNode.removeChild(before.nextSibling));
	}
}

function reinsertChildren(parent, target) {
	while (parent.firstChild) target.appendChild(parent.firstChild);
}

function reinsertAfter(before, target) {
	while (before.nextSibling) target.appendChild(before.nextSibling);
}

function reinsertBefore(after, target) {
	var parent = after.parentNode;
	while (parent.firstChild !== after) target.appendChild(parent.firstChild);
}

function destroyEach(iterations) {
	for (var i = 0; i < iterations.length; i += 1) {
		if (iterations[i]) iterations[i].d();
	}
}

function createFragment() {
	return document.createDocumentFragment();
}

function createElement(name) {
	return document.createElement(name);
}

function createSvgElement(name) {
	return document.createElementNS('http://www.w3.org/2000/svg', name);
}

function createText(data) {
	return document.createTextNode(data);
}

function createComment() {
	return document.createComment('');
}

function addListener(node, event, handler) {
	node.addEventListener(event, handler, false);
}

function removeListener(node, event, handler) {
	node.removeEventListener(event, handler, false);
}

function setAttribute(node, attribute, value) {
	node.setAttribute(attribute, value);
}

function setXlinkAttribute(node, attribute, value) {
	node.setAttributeNS('http://www.w3.org/1999/xlink', attribute, value);
}

function getBindingGroupValue(group) {
	var value = [];
	for (var i = 0; i < group.length; i += 1) {
		if (group[i].checked) value.push(group[i].__value);
	}
	return value;
}

function toNumber(value) {
	return value === '' ? undefined : +value;
}

function timeRangesToArray(ranges) {
	var array = [];
	for (var i = 0; i < ranges.length; i += 1) {
		array.push({ start: ranges.start(i), end: ranges.end(i) });
	}
	return array;
}

function children (element) {
	return Array.from(element.childNodes);
}

function claimElement (nodes, name, attributes, svg) {
	for (var i = 0; i < nodes.length; i += 1) {
		var node = nodes[i];
		if (node.nodeName === name) {
			for (var j = 0; j < node.attributes.length; j += 1) {
				var attribute = node.attributes[j];
				if (!attributes[attribute.name]) node.removeAttribute(attribute.name);
			}
			return nodes.splice(i, 1)[0]; // TODO strip unwanted attributes
		}
	}

	return svg ? createSvgElement(name) : createElement(name);
}

function claimText (nodes, data) {
	for (var i = 0; i < nodes.length; i += 1) {
		var node = nodes[i];
		if (node.nodeType === 3) {
			node.data = data;
			return nodes.splice(i, 1)[0];
		}
	}

	return createText(data);
}

function setInputType(input, type) {
	try {
		input.type = type;
	} catch (e) {}
}

function setStyle(node, key, value) {
	node.style.setProperty(key, value);
}

function linear(t) {
	return t;
}

function generateRule(
	a,
	b,
	delta,
	duration,
	ease,
	fn
) {
	var keyframes = '{\n';

	for (var p = 0; p <= 1; p += 16.666 / duration) {
		var t = a + delta * ease(p);
		keyframes += p * 100 + '%{' + fn(t) + '}\n';
	}

	return keyframes + '100% {' + fn(b) + '}\n}';
}

// https://github.com/darkskyapp/string-hash/blob/master/index.js
function hash(str) {
	var hash = 5381;
	var i = str.length;

	while (i--) hash = ((hash << 5) - hash) ^ str.charCodeAt(i);
	return hash >>> 0;
}

function wrapTransition(component, node, fn, params, intro, outgroup) {
	var obj = fn(node, params);
	var duration = obj.duration || 300;
	var ease = obj.easing || linear;
	var cssText;

	// TODO share <style> tag between all transitions?
	if (obj.css && !transitionManager.stylesheet) {
		var style = createElement('style');
		document.head.appendChild(style);
		transitionManager.stylesheet = style.sheet;
	}

	if (intro) {
		if (obj.css && obj.delay) {
			cssText = node.style.cssText;
			node.style.cssText += obj.css(0);
		}

		if (obj.tick) obj.tick(0);
	}

	return {
		t: intro ? 0 : 1,
		running: false,
		program: null,
		pending: null,
		run: function(intro, callback) {
			var program = {
				start: window.performance.now() + (obj.delay || 0),
				intro: intro,
				callback: callback
			};

			if (obj.delay) {
				this.pending = program;
			} else {
				this.start(program);
			}

			if (!this.running) {
				this.running = true;
				transitionManager.add(this);
			}
		},
		start: function(program) {
			component.fire(program.intro ? 'intro.start' : 'outro.start', { node: node });

			program.a = this.t;
			program.b = program.intro ? 1 : 0;
			program.delta = program.b - program.a;
			program.duration = duration * Math.abs(program.b - program.a);
			program.end = program.start + program.duration;

			if (obj.css) {
				if (obj.delay) node.style.cssText = cssText;

				program.rule = generateRule(
					program.a,
					program.b,
					program.delta,
					program.duration,
					ease,
					obj.css
				);

				transitionManager.addRule(program.rule, program.name = '__svelte_' + hash(program.rule));

				node.style.animation = (node.style.animation || '')
					.split(', ')
					.filter(function(anim) {
						// when introing, discard old animations if there are any
						return anim && (program.delta < 0 || !/__svelte/.test(anim));
					})
					.concat(program.name + ' ' + duration + 'ms linear 1 forwards')
					.join(', ');
			}

			this.program = program;
			this.pending = null;
		},
		update: function(now) {
			var program = this.program;
			if (!program) return;

			var p = now - program.start;
			this.t = program.a + program.delta * ease(p / program.duration);
			if (obj.tick) obj.tick(this.t);
		},
		done: function() {
			var program = this.program;
			this.t = program.b;
			if (obj.tick) obj.tick(this.t);
			if (obj.css) transitionManager.deleteRule(node, program.name);
			program.callback();
			program = null;
			this.running = !!this.pending;
		},
		abort: function() {
			if (obj.tick) obj.tick(1);
			if (obj.css) transitionManager.deleteRule(node, this.program.name);
			this.program = this.pending = null;
			this.running = false;
		}
	};
}

var transitionManager = {
	running: false,
	transitions: [],
	bound: null,
	stylesheet: null,
	activeRules: {},

	add: function(transition) {
		this.transitions.push(transition);

		if (!this.running) {
			this.running = true;
			requestAnimationFrame(this.bound || (this.bound = this.next.bind(this)));
		}
	},

	addRule: function(rule, name) {
		if (!this.activeRules[name]) {
			this.activeRules[name] = true;
			this.stylesheet.insertRule('@keyframes ' + name + ' ' + rule, this.stylesheet.cssRules.length);
		}
	},

	next: function() {
		this.running = false;

		var now = window.performance.now();
		var i = this.transitions.length;

		while (i--) {
			var transition = this.transitions[i];

			if (transition.program && now >= transition.program.end) {
				transition.done();
			}

			if (transition.pending && now >= transition.pending.start) {
				transition.start(transition.pending);
			}

			if (transition.running) {
				transition.update(now);
				this.running = true;
			} else if (!transition.pending) {
				this.transitions.splice(i, 1);
			}
		}

		if (this.running) {
			requestAnimationFrame(this.bound);
		} else if (this.stylesheet) {
			var i = this.stylesheet.cssRules.length;
			while (i--) this.stylesheet.deleteRule(i);
			this.activeRules = {};
		}
	},

	deleteRule: function(node, name) {
		node.style.animation = node.style.animation
			.split(', ')
			.filter(function(anim) {
				return anim.slice(0, name.length) !== name;
			})
			.join(', ');
	}
};

function blankObject() {
	return Object.create(null);
}

function destroy(detach) {
	this.destroy = noop;
	this.fire('destroy');
	this.set = this.get = noop;

	if (detach !== false) this._fragment.u();
	this._fragment.d();
	this._fragment = this._state = null;
}

function destroyDev(detach) {
	destroy.call(this, detach);
	this.destroy = function() {
		console.warn('Component was already destroyed');
	};
}

function differs(a, b) {
	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
}

function dispatchObservers(component, group, changed, newState, oldState) {
	for (var key in group) {
		if (!changed[key]) continue;

		var newValue = newState[key];
		var oldValue = oldState[key];

		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 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 get(key) {
	return key ? this._state[key] : this._state;
}

function init(component, options) {
	component.options = options;

	component._observers = { pre: blankObject(), post: blankObject() };
	component._handlers = blankObject();
	component._root = options._root || component;
	component._yield = options._yield;
	component._bind = options._bind;
}

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 observeDev(key, callback, options) {
	var c = (key = '' + key).search(/[^\w]/);
	if (c > -1) {
		var message =
			'The first argument to component.observe(...) must be the name of a top-level property';
		if (c > 0)
			message += ", i.e. '" + key.slice(0, c) + "' rather than '" + key + "'";

		throw new Error(message);
	}

	return observe.call(this, key, callback, options);
}

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 onDev(eventName, handler) {
	if (eventName === 'teardown') {
		console.warn(
			"Use component.on('destroy', ...) instead of component.on('teardown', ...) which has been deprecated and will be unsupported in Svelte 2"
		);
		return this.on('destroy', handler);
	}

	return on.call(this, eventName, handler);
}

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 _set(newState) {
	var oldState = this._state,
		changed = {},
		dirty = false;

	for (var key in newState) {
		if (differs(newState[key], oldState[key])) changed[key] = dirty = true;
	}
	if (!dirty) return;

	this._state = assign({}, oldState, newState);
	this._recompute(changed, this._state);
	if (this._bind) this._bind(changed, this._state);
	dispatchObservers(this, this._observers.pre, changed, this._state, oldState);
	this._fragment.p(changed, this._state);
	dispatchObservers(this, this._observers.post, changed, this._state, oldState);
}

function _setDev(newState) {
	if (typeof newState !== 'object') {
		throw new Error(
			this._debugName + ' .set was called without an object of data key-values to update.'
		);
	}

	this._checkReadOnly(newState);
	_set.call(this, newState);
}

function callAll(fns) {
	while (fns && fns.length) fns.pop()();
}

function _mount(target, anchor) {
	this._fragment.m(target, anchor);
}

function _unmount() {
	this._fragment.u();
}

var proto = {
	destroy: destroy,
	get: get,
	fire: fire,
	observe: observe,
	on: on,
	set: set,
	teardown: destroy,
	_recompute: noop,
	_set: _set,
	_mount: _mount,
	_unmount: _unmount
};

var protoDev = {
	destroy: destroyDev,
	get: get,
	fire: fire,
	observe: observeDev,
	on: onDev,
	set: set,
	teardown: destroyDev,
	_recompute: noop,
	_set: _setDev,
	_mount: _mount,
	_unmount: _unmount
};

export { blankObject, destroy, destroyDev, differs, dispatchObservers, fire, get, init, observe, observeDev, on, onDev, set, _set, _setDev, callAll, _mount, _unmount, proto, protoDev, appendNode, insertNode, detachNode, detachBetween, detachBefore, detachAfter, reinsertBetween, reinsertChildren, reinsertAfter, reinsertBefore, destroyEach, createFragment, createElement, createSvgElement, createText, createComment, addListener, removeListener, setAttribute, setXlinkAttribute, getBindingGroupValue, toNumber, timeRangesToArray, children, claimElement, claimText, setInputType, setStyle, linear, generateRule, hash, wrapTransition, transitionManager, noop, assign };