svelte/src/shared/index.js

import { assign } from './utils.js';
import { noop } from './utils.js';
export * from './animations.js';
export * from './await-block.js';
export * from './dom.js';
export * from './keyed-each.js';
export * from './spread.js';
export * from './ssr.js';
export * from './transitions.js';
export * from './utils.js';

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

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

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

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

export function _differs(a, b) {
	return a != a ? b == b : a !== b || ((a && typeof a === 'object') || typeof a === 'function');
}

export function _differsImmutable(a, b) {
	return a != a ? b == b : a !== b;
}

export 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) {
		var handler = handlers[i];

		if (!handler.__calling) {
			handler.__calling = true;
			handler.call(this, data);
			handler.__calling = false;
		}
	}
}

export function get() {
	return this._state;
}

export function init(component, options) {
	component._handlers = blankObject();
	component._bind = options._bind;

	component.options = options;
	component.root = options.root || component;
	component.store = options.store || component.root.store;
}

export function on(eventName, 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);
		}
	};
}

export function run(fn) {
	fn();
}

export 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;
}

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

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

	this._state = assign(assign({}, oldState), newState);
	this._recompute(changed, this._state);
	if (this._bind) this._bind(changed, this._state);

	if (this._fragment) {
		this.fire("state", { changed: changed, current: this._state, previous: oldState });
		this._fragment.p(changed, this._state);
		this.fire("update", { changed: changed, current: this._state, previous: oldState });
	}
}

export 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);
}

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

export function _mount(target, anchor) {
	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
}

export var PENDING = {};
export var SUCCESS = {};
export var FAILURE = {};

export function removeFromStore() {
	this.store._remove(this);
}

export var proto = {
	destroy,
	get,
	fire,
	on,
	set,
	_recompute: noop,
	_set,
	_mount,
	_differs
};

export var protoDev = {
	destroy: destroyDev,
	get,
	fire,
	on,
	set: setDev,
	_recompute: noop,
	_set,
	_mount,
	_differs
};