js工具代碼封裝(超長)1/3

 

/*!
 * Vue.js v2.5.16
 * (c) 2014-2018 Evan You
 * Released under the MIT License.
 */
(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
        typeof define === 'function' && define.amd ? define(factory) :
            (global.Vue = factory());
}(this, (function () { 'use strict';

    /*  */

    var emptyObject = Object.freeze({});

// these helpers produces better vm code in JS engines due to their
// explicitness and function inlining
    function isUndef (v) {
        return v === undefined || v === null
    }

    function isDef (v) {
        return v !== undefined && v !== null
    }

    function isTrue (v) {
        return v === true
    }

    function isFalse (v) {
        return v === false
    }

    /**
     * Check if value is primitive
     */
    function isPrimitive (value) {
        return (
            typeof value === 'string' ||
            typeof value === 'number' ||
            // $flow-disable-line
            typeof value === 'symbol' ||
            typeof value === 'boolean'
        )
    }

    /**
     * Quick object check - this is primarily used to tell
     * Objects from primitive values when we know the value
     * is a JSON-compliant type.
     */
    function isObject (obj) {
        return obj !== null && typeof obj === 'object'
    }

    /**
     * Get the raw type string of a value e.g. [object Object]
     */
    var _toString = Object.prototype.toString;

    function toRawType (value) {
        return _toString.call(value).slice(8, -1)
    }

    /**
     * Strict object type check. Only returns true
     * for plain JavaScript objects.
     */
    function isPlainObject (obj) {
        return _toString.call(obj) === '[object Object]'
    }

    function isRegExp (v) {
        return _toString.call(v) === '[object RegExp]'
    }

    /**
     * Check if val is a valid array index.
     */
    function isValidArrayIndex (val) {
        var n = parseFloat(String(val));
        return n >= 0 && Math.floor(n) === n && isFinite(val)
    }

    /**
     * Convert a value to a string that is actually rendered.
     */
    function toString (val) {
        return val == null
            ? ''
            : typeof val === 'object'
            ? JSON.stringify(val, null, 2)
            : String(val)
    }

    /**
     * Convert a input value to a number for persistence.
     * If the conversion fails, return original string.
     */
    function toNumber (val) {
        var n = parseFloat(val);
        return isNaN(n) ? val : n
    }

    /**
     * Make a map and return a function for checking if a key
     * is in that map.
     */
    function makeMap (
        str,
        expectsLowerCase
    ) {
        var map = Object.create(null);
        var list = str.split(',');
        for (var i = 0; i < list.length; i++) {
            map[list[i]] = true;
        }
        return expectsLowerCase
            ? function (val) { return map[val.toLowerCase()]; }
            : function (val) { return map[val]; }
    }

    /**
     * Check if a tag is a built-in tag.
     */
    var isBuiltInTag = makeMap('slot,component', true);

    /**
     * Check if a attribute is a reserved attribute.
     */
    var isReservedAttribute = makeMap('key,ref,slot,slot-scope,is');

    /**
     * Remove an item from an array
     */
    function remove (arr, item) {
        if (arr.length) {
            var index = arr.indexOf(item);
            if (index > -1) {
                return arr.splice(index, 1)
            }
        }
    }

    /**
     * Check whether the object has the property.
     */
    var hasOwnProperty = Object.prototype.hasOwnProperty;
    function hasOwn (obj, key) {
        return hasOwnProperty.call(obj, key)
    }

    /**
     * Create a cached version of a pure function.
     */
    function cached (fn) {
        var cache = Object.create(null);
        return (function cachedFn (str) {
            var hit = cache[str];
            return hit || (cache[str] = fn(str))
        })
    }

    /**
     * Camelize a hyphen-delimited string.
     */
    var camelizeRE = /-(\w)/g;
    var camelize = cached(function (str) {
        return str.replace(camelizeRE, function (_, c) { return c ? c.toUpperCase() : ''; })
    });

    /**
     * Capitalize a string.
     */
    var capitalize = cached(function (str) {
        return str.charAt(0).toUpperCase() + str.slice(1)
    });

    /**
     * Hyphenate a camelCase string.
     */
    var hyphenateRE = /\B([A-Z])/g;
    var hyphenate = cached(function (str) {
        return str.replace(hyphenateRE, '-$1').toLowerCase()
    });

    /**
     * Simple bind polyfill for environments that do not support it... e.g.
     * PhantomJS 1.x. Technically we don't need this anymore since native bind is
     * now more performant in most browsers, but removing it would be breaking for
     * code that was able to run in PhantomJS 1.x, so this must be kept for
     * backwards compatibility.
     */

    /* istanbul ignore next */
    function polyfillBind (fn, ctx) {
        function boundFn (a) {
            var l = arguments.length;
            return l
                ? l > 1
                ? fn.apply(ctx, arguments)
                : fn.call(ctx, a)
                : fn.call(ctx)
        }

        boundFn._length = fn.length;
        return boundFn
    }

    function nativeBind (fn, ctx) {
        return fn.bind(ctx)
    }

    var bind = Function.prototype.bind
        ? nativeBind
        : polyfillBind;

    /**
     * Convert an Array-like object to a real Array.
     */
    function toArray (list, start) {
        start = start || 0;
        var i = list.length - start;
        var ret = new Array(i);
        while (i--) {
            ret[i] = list[i + start];
        }
        return ret
    }

    /**
     * Mix properties into target object.
     */
    function extend (to, _from) {
        for (var key in _from) {
            to[key] = _from[key];
        }
        return to
    }

    /**
     * Merge an Array of Objects into a single Object.
     */
    function toObject (arr) {
        var res = {};
        for (var i = 0; i < arr.length; i++) {
            if (arr[i]) {
                extend(res, arr[i]);
            }
        }
        return res
    }

    /**
     * Perform no operation.
     * Stubbing args to make Flow happy without leaving useless transpiled code
     * with ...rest (https://flow.org/blog/2017/05/07/Strict-Function-Call-Arity/)
     */
    function noop (a, b, c) {}

    /**
     * Always return false.
     */
    var no = function (a, b, c) { return false; };

    /**
     * Return same value
     */
    var identity = function (_) { return _; };

    /**
     * Generate a static keys string from compiler modules.
     */
    function genStaticKeys (modules) {
        return modules.reduce(function (keys, m) {
            return keys.concat(m.staticKeys || [])
        }, []).join(',')
    }

    /**
     * Check if two values are loosely equal - that is,
     * if they are plain objects, do they have the same shape?
     */
    function looseEqual (a, b) {
        if (a === b) { return true }
        var isObjectA = isObject(a);
        var isObjectB = isObject(b);
        if (isObjectA && isObjectB) {
            try {
                var isArrayA = Array.isArray(a);
                var isArrayB = Array.isArray(b);
                if (isArrayA && isArrayB) {
                    return a.length === b.length && a.every(function (e, i) {
                            return looseEqual(e, b[i])
                        })
                } else if (!isArrayA && !isArrayB) {
                    var keysA = Object.keys(a);
                    var keysB = Object.keys(b);
                    return keysA.length === keysB.length && keysA.every(function (key) {
                            return looseEqual(a[key], b[key])
                        })
                } else {
                    /* istanbul ignore next */
                    return false
                }
            } catch (e) {
                /* istanbul ignore next */
                return false
            }
        } else if (!isObjectA && !isObjectB) {
            return String(a) === String(b)
        } else {
            return false
        }
    }

    function looseIndexOf (arr, val) {
        for (var i = 0; i < arr.length; i++) {
            if (looseEqual(arr[i], val)) { return i }
        }
        return -1
    }

    /**
     * Ensure a function is called only once.
     */
    function once (fn) {
        var called = false;
        return function () {
            if (!called) {
                called = true;
                fn.apply(this, arguments);
            }
        }
    }

    var SSR_ATTR = 'data-server-rendered';

    var ASSET_TYPES = [
        'component',
        'directive',
        'filter'
    ];

    var LIFECYCLE_HOOKS = [
        'beforeCreate',
        'created',
        'beforeMount',
        'mounted',
        'beforeUpdate',
        'updated',
        'beforeDestroy',
        'destroyed',
        'activated',
        'deactivated',
        'errorCaptured'
    ];

    /*  */

    var config = ({
        /**
         * Option merge strategies (used in core/util/options)
         */
        // $flow-disable-line
        optionMergeStrategies: Object.create(null),

        /**
         * Whether to suppress warnings.
         */
        silent: false,

        /**
         * Show production mode tip message on boot?
         */
        productionTip: "development" !== 'production',

        /**
         * Whether to enable devtools
         */
        devtools: "development" !== 'production',

        /**
         * Whether to record perf
         */
        performance: false,

        /**
         * Error handler for watcher errors
         */
        errorHandler: null,

        /**
         * Warn handler for watcher warns
         */
        warnHandler: null,

        /**
         * Ignore certain custom elements
         */
        ignoredElements: [],

        /**
         * Custom user key aliases for v-on
         */
        // $flow-disable-line
        keyCodes: Object.create(null),

        /**
         * Check if a tag is reserved so that it cannot be registered as a
         * component. This is platform-dependent and may be overwritten.
         */
        isReservedTag: no,

        /**
         * Check if an attribute is reserved so that it cannot be used as a component
         * prop. This is platform-dependent and may be overwritten.
         */
        isReservedAttr: no,

        /**
         * Check if a tag is an unknown element.
         * Platform-dependent.
         */
        isUnknownElement: no,

        /**
         * Get the namespace of an element
         */
        getTagNamespace: noop,

        /**
         * Parse the real tag name for the specific platform.
         */
        parsePlatformTagName: identity,

        /**
         * Check if an attribute must be bound using property, e.g. value
         * Platform-dependent.
         */
        mustUseProp: no,

        /**
         * Exposed for legacy reasons
         */
        _lifecycleHooks: LIFECYCLE_HOOKS
    })

    /*  */

    /**
     * Check if a string starts with $ or _
     */
    function isReserved (str) {
        var c = (str + '').charCodeAt(0);
        return c === 0x24 || c === 0x5F
    }

    /**
     * Define a property.
     */
    function def (obj, key, val, enumerable) {
        Object.defineProperty(obj, key, {
            value: val,
            enumerable: !!enumerable,
            writable: true,
            configurable: true
        });
    }

    /**
     * Parse simple path.
     */
    var bailRE = /[^\w.$]/;
    function parsePath (path) {
        if (bailRE.test(path)) {
            return
        }
        var segments = path.split('.');
        return function (obj) {
            for (var i = 0; i < segments.length; i++) {
                if (!obj) { return }
                obj = obj[segments[i]];
            }
            return obj
        }
    }

    /*  */

// can we use __proto__?
    var hasProto = '__proto__' in {};

// Browser environment sniffing
    var inBrowser = typeof window !== 'undefined';
    var inWeex = typeof WXEnvironment !== 'undefined' && !!WXEnvironment.platform;
    var weexPlatform = inWeex && WXEnvironment.platform.toLowerCase();
    var UA = inBrowser && window.navigator.userAgent.toLowerCase();
    var isIE = UA && /msie|trident/.test(UA);
    var isIE9 = UA && UA.indexOf('msie 9.0') > 0;
    var isEdge = UA && UA.indexOf('edge/') > 0;
    var isAndroid = (UA && UA.indexOf('android') > 0) || (weexPlatform === 'android');
    var isIOS = (UA && /iphone|ipad|ipod|ios/.test(UA)) || (weexPlatform === 'ios');
    var isChrome = UA && /chrome\/\d+/.test(UA) && !isEdge;

// Firefox has a "watch" function on Object.prototype...
    var nativeWatch = ({}).watch;

    var supportsPassive = false;
    if (inBrowser) {
        try {
            var opts = {};
            Object.defineProperty(opts, 'passive', ({
                get: function get () {
                    /* istanbul ignore next */
                    supportsPassive = true;
                }
            })); // https://github.com/facebook/flow/issues/285
            window.addEventListener('test-passive', null, opts);
        } catch (e) {}
    }

// this needs to be lazy-evaled because vue may be required before
// vue-server-renderer can set VUE_ENV
    var _isServer;
    var isServerRendering = function () {
        if (_isServer === undefined) {
            /* istanbul ignore if */
            if (!inBrowser && !inWeex && typeof global !== 'undefined') {
                // detect presence of vue-server-renderer and avoid
                // Webpack shimming the process
                _isServer = global['process'].env.VUE_ENV === 'server';
            } else {
                _isServer = false;
            }
        }
        return _isServer
    };

// detect devtools
    var devtools = inBrowser && window.__VUE_DEVTOOLS_GLOBAL_HOOK__;

    /* istanbul ignore next */
    function isNative (Ctor) {
        return typeof Ctor === 'function' && /native code/.test(Ctor.toString())
    }

    var hasSymbol =
        typeof Symbol !== 'undefined' && isNative(Symbol) &&
        typeof Reflect !== 'undefined' && isNative(Reflect.ownKeys);

    var _Set;
    /* istanbul ignore if */ // $flow-disable-line
    if (typeof Set !== 'undefined' && isNative(Set)) {
        // use native Set when available.
        _Set = Set;
    } else {
        // a non-standard Set polyfill that only works with primitive keys.
        _Set = (function () {
            function Set () {
                this.set = Object.create(null);
            }
            Set.prototype.has = function has (key) {
                return this.set[key] === true
            };
            Set.prototype.add = function add (key) {
                this.set[key] = true;
            };
            Set.prototype.clear = function clear () {
                this.set = Object.create(null);
            };

            return Set;
        }());
    }

    /*  */

    var warn = noop;
    var tip = noop;
    var generateComponentTrace = (noop); // work around flow check
    var formatComponentName = (noop);

    {
        var hasConsole = typeof console !== 'undefined';
        var classifyRE = /(?:^|[-_])(\w)/g;
        var classify = function (str) { return str
            .replace(classifyRE, function (c) { return c.toUpperCase(); })
            .replace(/[-_]/g, ''); };

        warn = function (msg, vm) {
            var trace = vm ? generateComponentTrace(vm) : '';

            if (config.warnHandler) {
                config.warnHandler.call(null, msg, vm, trace);
            } else if (hasConsole && (!config.silent)) {
                console.error(("[Vue warn]: " + msg + trace));
            }
        };

        tip = function (msg, vm) {
            if (hasConsole && (!config.silent)) {
                console.warn("[Vue tip]: " + msg + (
                        vm ? generateComponentTrace(vm) : ''
                    ));
            }
        };

        formatComponentName = function (vm, includeFile) {
            if (vm.$root === vm) {
                return '<Root>'
            }
            var options = typeof vm === 'function' && vm.cid != null
                ? vm.options
                : vm._isVue
                ? vm.$options || vm.constructor.options
                : vm || {};
            var name = options.name || options._componentTag;
            var file = options.__file;
            if (!name && file) {
                var match = file.match(/([^/\\]+)\.vue$/);
                name = match && match[1];
            }

            return (
                (name ? ("<" + (classify(name)) + ">") : "<Anonymous>") +
                (file && includeFile !== false ? (" at " + file) : '')
            )
        };

        var repeat = function (str, n) {
            var res = '';
            while (n) {
                if (n % 2 === 1) { res += str; }
                if (n > 1) { str += str; }
                n >>= 1;
            }
            return res
        };

        generateComponentTrace = function (vm) {
            if (vm._isVue && vm.$parent) {
                var tree = [];
                var currentRecursiveSequence = 0;
                while (vm) {
                    if (tree.length > 0) {
                        var last = tree[tree.length - 1];
                        if (last.constructor === vm.constructor) {
                            currentRecursiveSequence++;
                            vm = vm.$parent;
                            continue
                        } else if (currentRecursiveSequence > 0) {
                            tree[tree.length - 1] = [last, currentRecursiveSequence];
                            currentRecursiveSequence = 0;
                        }
                    }
                    tree.push(vm);
                    vm = vm.$parent;
                }
                return '\n\nfound in\n\n' + tree
                        .map(function (vm, i) { return ("" + (i === 0 ? '---> ' : repeat(' ', 5 + i * 2)) + (Array.isArray(vm)
                            ? ((formatComponentName(vm[0])) + "... (" + (vm[1]) + " recursive calls)")
                            : formatComponentName(vm))); })
                        .join('\n')
            } else {
                return ("\n\n(found in " + (formatComponentName(vm)) + ")")
            }
        };
    }

    /*  */


    var uid = 0;

    /**
     * A dep is an observable that can have multiple
     * directives subscribing to it.
     */
    var Dep = function Dep () {
        this.id = uid++;
        this.subs = [];
    };

    Dep.prototype.addSub = function addSub (sub) {
        this.subs.push(sub);
    };

    Dep.prototype.removeSub = function removeSub (sub) {
        remove(this.subs, sub);
    };

    Dep.prototype.depend = function depend () {
        if (Dep.target) {
            Dep.target.addDep(this);
        }
    };

    Dep.prototype.notify = function notify () {
        // stabilize the subscriber list first
        var subs = this.subs.slice();
        for (var i = 0, l = subs.length; i < l; i++) {
            subs[i].update();
        }
    };

// the current target watcher being evaluated.
// this is globally unique because there could be only one
// watcher being evaluated at any time.
    Dep.target = null;
    var targetStack = [];

    function pushTarget (_target) {
        if (Dep.target) { targetStack.push(Dep.target); }
        Dep.target = _target;
    }

    function popTarget () {
        Dep.target = targetStack.pop();
    }

    /*  */

    var VNode = function VNode (
        tag,
        data,
        children,
        text,
        elm,
        context,
        componentOptions,
        asyncFactory
    ) {
        this.tag = tag;
        this.data = data;
        this.children = children;
        this.text = text;
        this.elm = elm;
        this.ns = undefined;
        this.context = context;
        this.fnContext = undefined;
        this.fnOptions = undefined;
        this.fnScopeId = undefined;
        this.key = data && data.key;
        this.componentOptions = componentOptions;
        this.componentInstance = undefined;
        this.parent = undefined;
        this.raw = false;
        this.isStatic = false;
        this.isRootInsert = true;
        this.isComment = false;
        this.isCloned = false;
        this.isOnce = false;
        this.asyncFactory = asyncFactory;
        this.asyncMeta = undefined;
        this.isAsyncPlaceholder = false;
    };

    var prototypeAccessors = { child: { configurable: true } };

// DEPRECATED: alias for componentInstance for backwards compat.
    /* istanbul ignore next */
    prototypeAccessors.child.get = function () {
        return this.componentInstance
    };

    Object.defineProperties( VNode.prototype, prototypeAccessors );

    var createEmptyVNode = function (text) {
        if ( text === void 0 ) text = '';

        var node = new VNode();
        node.text = text;
        node.isComment = true;
        return node
    };

    function createTextVNode (val) {
        return new VNode(undefined, undefined, undefined, String(val))
    }

// optimized shallow clone
// used for static nodes and slot nodes because they may be reused across
// multiple renders, cloning them avoids errors when DOM manipulations rely
// on their elm reference.
    function cloneVNode (vnode) {
        var cloned = new VNode(
            vnode.tag,
            vnode.data,
            vnode.children,
            vnode.text,
            vnode.elm,
            vnode.context,
            vnode.componentOptions,
            vnode.asyncFactory
        );
        cloned.ns = vnode.ns;
        cloned.isStatic = vnode.isStatic;
        cloned.key = vnode.key;
        cloned.isComment = vnode.isComment;
        cloned.fnContext = vnode.fnContext;
        cloned.fnOptions = vnode.fnOptions;
        cloned.fnScopeId = vnode.fnScopeId;
        cloned.isCloned = true;
        return cloned
    }

    /*
     * not type checking this file because flow doesn't play well with
     * dynamically accessing methods on Array prototype
     */

    var arrayProto = Array.prototype;
    var arrayMethods = Object.create(arrayProto);

    var methodsToPatch = [
        'push',
        'pop',
        'shift',
        'unshift',
        'splice',
        'sort',
        'reverse'
    ];

    /**
     * Intercept mutating methods and emit events
     */
    methodsToPatch.forEach(function (method) {
        // cache original method
        var original = arrayProto[method];
        def(arrayMethods, method, function mutator () {
            var args = [], len = arguments.length;
            while ( len-- ) args[ len ] = arguments[ len ];

            var result = original.apply(this, args);
            var ob = this.__ob__;
            var inserted;
            switch (method) {
                case 'push':
                case 'unshift':
                    inserted = args;
                    break
                case 'splice':
                    inserted = args.slice(2);
                    break
            }
            if (inserted) { ob.observeArray(inserted); }
            // notify change
            ob.dep.notify();
            return result
        });
    });

    /*  */

    var arrayKeys = Object.getOwnPropertyNames(arrayMethods);

    /**
     * In some cases we may want to disable observation inside a component's
     * update computation.
     */
    var shouldObserve = true;

    function toggleObserving (value) {
        shouldObserve = value;
    }

    /**
     * Observer class that is attached to each observed
     * object. Once attached, the observer converts the target
     * object's property keys into getter/setters that
     * collect dependencies and dispatch updates.
     */
    var Observer = function Observer (value) {
        this.value = value;
        this.dep = new Dep();
        this.vmCount = 0;
        def(value, '__ob__', this);
        if (Array.isArray(value)) {
            var augment = hasProto
                ? protoAugment
                : copyAugment;
            augment(value, arrayMethods, arrayKeys);
            this.observeArray(value);
        } else {
            this.walk(value);
        }
    };

    /**
     * Walk through each property and convert them into
     * getter/setters. This method should only be called when
     * value type is Object.
     */
    Observer.prototype.walk = function walk (obj) {
        var keys = Object.keys(obj);
        for (var i = 0; i < keys.length; i++) {
            defineReactive(obj, keys[i]);
        }
    };

    /**
     * Observe a list of Array items.
     */
    Observer.prototype.observeArray = function observeArray (items) {
        for (var i = 0, l = items.length; i < l; i++) {
            observe(items[i]);
        }
    };

// helpers

    /**
     * Augment an target Object or Array by intercepting
     * the prototype chain using __proto__
     */
    function protoAugment (target, src, keys) {
        /* eslint-disable no-proto */
        target.__proto__ = src;
        /* eslint-enable no-proto */
    }

    /**
     * Augment an target Object or Array by defining
     * hidden properties.
     */
    /* istanbul ignore next */
    function copyAugment (target, src, keys) {
        for (var i = 0, l = keys.length; i < l; i++) {
            var key = keys[i];
            def(target, key, src[key]);
        }
    }

    /**
     * Attempt to create an observer instance for a value,
     * returns the new observer if successfully observed,
     * or the existing observer if the value already has one.
     */
    function observe (value, asRootData) {
        if (!isObject(value) || value instanceof VNode) {
            return
        }
        var ob;
        if (hasOwn(value, '__ob__') && value.__ob__ instanceof Observer) {
            ob = value.__ob__;
        } else if (
            shouldObserve &&
            !isServerRendering() &&
            (Array.isArray(value) || isPlainObject(value)) &&
            Object.isExtensible(value) &&
            !value._isVue
        ) {
            ob = new Observer(value);
        }
        if (asRootData && ob) {
            ob.vmCount++;
        }
        return ob
    }

    /**
     * Define a reactive property on an Object.
     */
    function defineReactive (
        obj,
        key,
        val,
        customSetter,
        shallow
    ) {
        var dep = new Dep();

        var property = Object.getOwnPropertyDescriptor(obj, key);
        if (property && property.configurable === false) {
            return
        }

        // cater for pre-defined getter/setters
        var getter = property && property.get;
        if (!getter && arguments.length === 2) {
            val = obj[key];
        }
        var setter = property && property.set;

        var childOb = !shallow && observe(val);
        Object.defineProperty(obj, key, {
            enumerable: true,
            configurable: true,
            get: function reactiveGetter () {
                var value = getter ? getter.call(obj) : val;
                if (Dep.target) {
                    dep.depend();
                    if (childOb) {
                        childOb.dep.depend();
                        if (Array.isArray(value)) {
                            dependArray(value);
                        }
                    }
                }
                return value
            },
            set: function reactiveSetter (newVal) {
                var value = getter ? getter.call(obj) : val;
                /* eslint-disable no-self-compare */
                if (newVal === value || (newVal !== newVal && value !== value)) {
                    return
                }
                /* eslint-enable no-self-compare */
                if ("development" !== 'production' && customSetter) {
                    customSetter();
                }
                if (setter) {
                    setter.call(obj, newVal);
                } else {
                    val = newVal;
                }
                childOb = !shallow && observe(newVal);
                dep.notify();
            }
        });
    }

    /**
     * Set a property on an object. Adds the new property and
     * triggers change notification if the property doesn't
     * already exist.
     */
    function set (target, key, val) {
        if ("development" !== 'production' &&
            (isUndef(target) || isPrimitive(target))
        ) {
            warn(("Cannot set reactive property on undefined, null, or primitive value: " + ((target))));
        }
        if (Array.isArray(target) && isValidArrayIndex(key)) {
            target.length = Math.max(target.length, key);
            target.splice(key, 1, val);
            return val
        }
        if (key in target && !(key in Object.prototype)) {
            target[key] = val;
            return val
        }
        var ob = (target).__ob__;
        if (target._isVue || (ob && ob.vmCount)) {
            "development" !== 'production' && warn(
                'Avoid adding reactive properties to a Vue instance or its root $data ' +
                'at runtime - declare it upfront in the data option.'
            );
            return val
        }
        if (!ob) {
            target[key] = val;
            return val
        }
        defineReactive(ob.value, key, val);
        ob.dep.notify();
        return val
    }

    /**
     * Delete a property and trigger change if necessary.
     */
    function del (target, key) {
        if ("development" !== 'production' &&
            (isUndef(target) || isPrimitive(target))
        ) {
            warn(("Cannot delete reactive property on undefined, null, or primitive value: " + ((target))));
        }
        if (Array.isArray(target) && isValidArrayIndex(key)) {
            target.splice(key, 1);
            return
        }
        var ob = (target).__ob__;
        if (target._isVue || (ob && ob.vmCount)) {
            "development" !== 'production' && warn(
                'Avoid deleting properties on a Vue instance or its root $data ' +
                '- just set it to null.'
            );
            return
        }
        if (!hasOwn(target, key)) {
            return
        }
        delete target[key];
        if (!ob) {
            return
        }
        ob.dep.notify();
    }

    /**
     * Collect dependencies on array elements when the array is touched, since
     * we cannot intercept array element access like property getters.
     */
    function dependArray (value) {
        for (var e = (void 0), i = 0, l = value.length; i < l; i++) {
            e = value[i];
            e && e.__ob__ && e.__ob__.dep.depend();
            if (Array.isArray(e)) {
                dependArray(e);
            }
        }
    }

    /*  */

    /**
     * Option overwriting strategies are functions that handle
     * how to merge a parent option value and a child option
     * value into the final value.
     */
    var strats = config.optionMergeStrategies;

    /**
     * Options with restrictions
     */
    {
        strats.el = strats.propsData = function (parent, child, vm, key) {
            if (!vm) {
                warn(
                    "option \"" + key + "\" can only be used during instance " +
                    'creation with the `new` keyword.'
                );
            }
            return defaultStrat(parent, child)
        };
    }

    /**
     * Helper that recursively merges two data objects together.
     */
    function mergeData (to, from) {
        if (!from) { return to }
        var key, toVal, fromVal;
        var keys = Object.keys(from);
        for (var i = 0; i < keys.length; i++) {
            key = keys[i];
            toVal = to[key];
            fromVal = from[key];
            if (!hasOwn(to, key)) {
                set(to, key, fromVal);
            } else if (isPlainObject(toVal) && isPlainObject(fromVal)) {
                mergeData(toVal, fromVal);
            }
        }
        return to
    }

    /**
     * Data
     */
    function mergeDataOrFn (
        parentVal,
        childVal,
        vm
    ) {
        if (!vm) {
            // in a Vue.extend merge, both should be functions
            if (!childVal) {
                return parentVal
            }
            if (!parentVal) {
                return childVal
            }
            // when parentVal & childVal are both present,
            // we need to return a function that returns the
            // merged result of both functions... no need to
            // check if parentVal is a function here because
            // it has to be a function to pass previous merges.
            return function mergedDataFn () {
                return mergeData(
                    typeof childVal === 'function' ? childVal.call(this, this) : childVal,
                    typeof parentVal === 'function' ? parentVal.call(this, this) : parentVal
                )
            }
        } else {
            return function mergedInstanceDataFn () {
                // instance merge
                var instanceData = typeof childVal === 'function'
                    ? childVal.call(vm, vm)
                    : childVal;
                var defaultData = typeof parentVal === 'function'
                    ? parentVal.call(vm, vm)
                    : parentVal;
                if (instanceData) {
                    return mergeData(instanceData, defaultData)
                } else {
                    return defaultData
                }
            }
        }
    }

    strats.data = function (
        parentVal,
        childVal,
        vm
    ) {
        if (!vm) {
            if (childVal && typeof childVal !== 'function') {
                "development" !== 'production' && warn(
                    'The "data" option should be a function ' +
                    'that returns a per-instance value in component ' +
                    'definitions.',
                    vm
                );

                return parentVal
            }
            return mergeDataOrFn(parentVal, childVal)
        }

        return mergeDataOrFn(parentVal, childVal, vm)
    };

    /**
     * Hooks and props are merged as arrays.
     */
    function mergeHook (
        parentVal,
        childVal
    ) {
        return childVal
            ? parentVal
            ? parentVal.concat(childVal)
            : Array.isArray(childVal)
            ? childVal
            : [childVal]
            : parentVal
    }

    LIFECYCLE_HOOKS.forEach(function (hook) {
        strats[hook] = mergeHook;
    });

    /**
     * Assets
     *
     * When a vm is present (instance creation), we need to do
     * a three-way merge between constructor options, instance
     * options and parent options.
     */
    function mergeAssets (
        parentVal,
        childVal,
        vm,
        key
    ) {
        var res = Object.create(parentVal || null);
        if (childVal) {
            "development" !== 'production' && assertObjectType(key, childVal, vm);
            return extend(res, childVal)
        } else {
            return res
        }
    }

    ASSET_TYPES.forEach(function (type) {
        strats[type + 's'] = mergeAssets;
    });

    /**
     * Watchers.
     *
     * Watchers hashes should not overwrite one
     * another, so we merge them as arrays.
     */
    strats.watch = function (
        parentVal,
        childVal,
        vm,
        key
    ) {
        // work around Firefox's Object.prototype.watch...
        if (parentVal === nativeWatch) { parentVal = undefined; }
        if (childVal === nativeWatch) { childVal = undefined; }
        /* istanbul ignore if */
        if (!childVal) { return Object.create(parentVal || null) }
        {
            assertObjectType(key, childVal, vm);
        }
        if (!parentVal) { return childVal }
        var ret = {};
        extend(ret, parentVal);
        for (var key$1 in childVal) {
            var parent = ret[key$1];
            var child = childVal[key$1];
            if (parent && !Array.isArray(parent)) {
                parent = [parent];
            }
            ret[key$1] = parent
                ? parent.concat(child)
                : Array.isArray(child) ? child : [child];
        }
        return ret
    };

    /**
     * Other object hashes.
     */
    strats.props =
        strats.methods =
            strats.inject =
                strats.computed = function (
                    parentVal,
                    childVal,
                    vm,
                    key
                ) {
                    if (childVal && "development" !== 'production') {
                        assertObjectType(key, childVal, vm);
                    }
                    if (!parentVal) { return childVal }
                    var ret = Object.create(null);
                    extend(ret, parentVal);
                    if (childVal) { extend(ret, childVal); }
                    return ret
                };
    strats.provide = mergeDataOrFn;

    /**
     * Default strategy.
     */
    var defaultStrat = function (parentVal, childVal) {
        return childVal === undefined
            ? parentVal
            : childVal
    };

    /**
     * Validate component names
     */
    function checkComponents (options) {
        for (var key in options.components) {
            validateComponentName(key);
        }
    }

    function validateComponentName (name) {
        if (!/^[a-zA-Z][\w-]*$/.test(name)) {
            warn(
                'Invalid component name: "' + name + '". Component names ' +
                'can only contain alphanumeric characters and the hyphen, ' +
                'and must start with a letter.'
            );
        }
        if (isBuiltInTag(name) || config.isReservedTag(name)) {
            warn(
                'Do not use built-in or reserved HTML elements as component ' +
                'id: ' + name
            );
        }
    }

    /**
     * Ensure all props option syntax are normalized into the
     * Object-based format.
     */
    function normalizeProps (options, vm) {
        var props = options.props;
        if (!props) { return }
        var res = {};
        var i, val, name;
        if (Array.isArray(props)) {
            i = props.length;
            while (i--) {
                val = props[i];
                if (typeof val === 'string') {
                    name = camelize(val);
                    res[name] = { type: null };
                } else {
                    warn('props must be strings when using array syntax.');
                }
            }
        } else if (isPlainObject(props)) {
            for (var key in props) {
                val = props[key];
                name = camelize(key);
                res[name] = isPlainObject(val)
                    ? val
                    : { type: val };
            }
        } else {
            warn(
                "Invalid value for option \"props\": expected an Array or an Object, " +
                "but got " + (toRawType(props)) + ".",
                vm
            );
        }
        options.props = res;
    }

    /**
     * Normalize all injections into Object-based format
     */
    function normalizeInject (options, vm) {
        var inject = options.inject;
        if (!inject) { return }
        var normalized = options.inject = {};
        if (Array.isArray(inject)) {
            for (var i = 0; i < inject.length; i++) {
                normalized[inject[i]] = { from: inject[i] };
            }
        } else if (isPlainObject(inject)) {
            for (var key in inject) {
                var val = inject[key];
                normalized[key] = isPlainObject(val)
                    ? extend({ from: key }, val)
                    : { from: val };
            }
        } else {
            warn(
                "Invalid value for option \"inject\": expected an Array or an Object, " +
                "but got " + (toRawType(inject)) + ".",
                vm
            );
        }
    }

    /**
     * Normalize raw function directives into object format.
     */
    function normalizeDirectives (options) {
        var dirs = options.directives;
        if (dirs) {
            for (var key in dirs) {
                var def = dirs[key];
                if (typeof def === 'function') {
                    dirs[key] = { bind: def, update: def };
                }
            }
        }
    }

    function assertObjectType (name, value, vm) {
        if (!isPlainObject(value)) {
            warn(
                "Invalid value for option \"" + name + "\": expected an Object, " +
                "but got " + (toRawType(value)) + ".",
                vm
            );
        }
    }

    /**
     * Merge two option objects into a new one.
     * Core utility used in both instantiation and inheritance.
     */
    function mergeOptions (
        parent,
        child,
        vm
    ) {
        {
            checkComponents(child);
        }

        if (typeof child === 'function') {
            child = child.options;
        }

        normalizeProps(child, vm);
        normalizeInject(child, vm);
        normalizeDirectives(child);
        var extendsFrom = child.extends;
        if (extendsFrom) {
            parent = mergeOptions(parent, extendsFrom, vm);
        }
        if (child.mixins) {
            for (var i = 0, l = child.mixins.length; i < l; i++) {
                parent = mergeOptions(parent, child.mixins[i], vm);
            }
        }
        var options = {};
        var key;
        for (key in parent) {
            mergeField(key);
        }
        for (key in child) {
            if (!hasOwn(parent, key)) {
                mergeField(key);
            }
        }
        function mergeField (key) {
            var strat = strats[key] || defaultStrat;
            options[key] = strat(parent[key], child[key], vm, key);
        }
        return options
    }

    /**
     * Resolve an asset.
     * This function is used because child instances need access
     * to assets defined in its ancestor chain.
     */
    function resolveAsset (
        options,
        type,
        id,
        warnMissing
    ) {
        /* istanbul ignore if */
        if (typeof id !== 'string') {
            return
        }
        var assets = options[type];
        // check local registration variations first
        if (hasOwn(assets, id)) { return assets[id] }
        var camelizedId = camelize(id);
        if (hasOwn(assets, camelizedId)) { return assets[camelizedId] }
        var PascalCaseId = capitalize(camelizedId);
        if (hasOwn(assets, PascalCaseId)) { return assets[PascalCaseId] }
        // fallback to prototype chain
        var res = assets[id] || assets[camelizedId] || assets[PascalCaseId];
        if ("development" !== 'production' && warnMissing && !res) {
            warn(
                'Failed to resolve ' + type.slice(0, -1) + ': ' + id,
                options
            );
        }
        return res
    }

    /*  */

    function validateProp (
        key,
        propOptions,
        propsData,
        vm
    ) {
        var prop = propOptions[key];
        var absent = !hasOwn(propsData, key);
        var value = propsData[key];
        // boolean casting
        var booleanIndex = getTypeIndex(Boolean, prop.type);
        if (booleanIndex > -1) {
            if (absent && !hasOwn(prop, 'default')) {
                value = false;
            } else if (value === '' || value === hyphenate(key)) {
                // only cast empty string / same name to boolean if
                // boolean has higher priority
                var stringIndex = getTypeIndex(String, prop.type);
                if (stringIndex < 0 || booleanIndex < stringIndex) {
                    value = true;
                }
            }
        }
        // check default value
        if (value === undefined) {
            value = getPropDefaultValue(vm, prop, key);
            // since the default value is a fresh copy,
            // make sure to observe it.
            var prevShouldObserve = shouldObserve;
            toggleObserving(true);
            observe(value);
            toggleObserving(prevShouldObserve);
        }
        {
            assertProp(prop, key, value, vm, absent);
        }
        return value
    }

    /**
     * Get the default value of a prop.
     */
    function getPropDefaultValue (vm, prop, key) {
        // no default, return undefined
        if (!hasOwn(prop, 'default')) {
            return undefined
        }
        var def = prop.default;
        // warn against non-factory defaults for Object & Array
        if ("development" !== 'production' && isObject(def)) {
            warn(
                'Invalid default value for prop "' + key + '": ' +
                'Props with type Object/Array must use a factory function ' +
                'to return the default value.',
                vm
            );
        }
        // the raw prop value was also undefined from previous render,
        // return previous default value to avoid unnecessary watcher trigger
        if (vm && vm.$options.propsData &&
            vm.$options.propsData[key] === undefined &&
            vm._props[key] !== undefined
        ) {
            return vm._props[key]
        }
        // call factory function for non-Function types
        // a value is Function if its prototype is function even across different execution context
        return typeof def === 'function' && getType(prop.type) !== 'Function'
            ? def.call(vm)
            : def
    }

    /**
     * Assert whether a prop is valid.
     */
    function assertProp (
        prop,
        name,
        value,
        vm,
        absent
    ) {
        if (prop.required && absent) {
            warn(
                'Missing required prop: "' + name + '"',
                vm
            );
            return
        }
        if (value == null && !prop.required) {
            return
        }
        var type = prop.type;
        var valid = !type || type === true;
        var expectedTypes = [];
        if (type) {
            if (!Array.isArray(type)) {
                type = [type];
            }
            for (var i = 0; i < type.length && !valid; i++) {
                var assertedType = assertType(value, type[i]);
                expectedTypes.push(assertedType.expectedType || '');
                valid = assertedType.valid;
            }
        }
        if (!valid) {
            warn(
                "Invalid prop: type check failed for prop \"" + name + "\"." +
                " Expected " + (expectedTypes.map(capitalize).join(', ')) +
                ", got " + (toRawType(value)) + ".",
                vm
            );
            return
        }
        var validator = prop.validator;
        if (validator) {
            if (!validator(value)) {
                warn(
                    'Invalid prop: custom validator check failed for prop "' + name + '".',
                    vm
                );
            }
        }
    }

    var simpleCheckRE = /^(String|Number|Boolean|Function|Symbol)$/;

    function assertType (value, type) {
        var valid;
        var expectedType = getType(type);
        if (simpleCheckRE.test(expectedType)) {
            var t = typeof value;
            valid = t === expectedType.toLowerCase();
            // for primitive wrapper objects
            if (!valid && t === 'object') {
                valid = value instanceof type;
            }
        } else if (expectedType === 'Object') {
            valid = isPlainObject(value);
        } else if (expectedType === 'Array') {
            valid = Array.isArray(value);
        } else {
            valid = value instanceof type;
        }
        return {
            valid: valid,
            expectedType: expectedType
        }
    }

    /**
     * Use function string name to check built-in types,
     * because a simple equality check will fail when running
     * across different vms / iframes.
     */
    function getType (fn) {
        var match = fn && fn.toString().match(/^\s*function (\w+)/);
        return match ? match[1] : ''
    }

    function isSameType (a, b) {
        return getType(a) === getType(b)
    }

    function getTypeIndex (type, expectedTypes) {
        if (!Array.isArray(expectedTypes)) {
            return isSameType(expectedTypes, type) ? 0 : -1
        }
        for (var i = 0, len = expectedTypes.length; i < len; i++) {
            if (isSameType(expectedTypes[i], type)) {
                return i
            }
        }
        return -1
    }

    /*  */

    function handleError (err, vm, info) {
        if (vm) {
            var cur = vm;
            while ((cur = cur.$parent)) {
                var hooks = cur.$options.errorCaptured;
                if (hooks) {
                    for (var i = 0; i < hooks.length; i++) {
                        try {
                            var capture = hooks[i].call(cur, err, vm, info) === false;
                            if (capture) { return }
                        } catch (e) {
                            globalHandleError(e, cur, 'errorCaptured hook');
                        }
                    }
                }
            }
        }
        globalHandleError(err, vm, info);
    }

    function globalHandleError (err, vm, info) {
        if (config.errorHandler) {
            try {
                return config.errorHandler.call(null, err, vm, info)
            } catch (e) {
                logError(e, null, 'config.errorHandler');
            }
        }
        logError(err, vm, info);
    }

    function logError (err, vm, info) {
        {
            warn(("Error in " + info + ": \"" + (err.toString()) + "\""), vm);
        }
        /* istanbul ignore else */
        if ((inBrowser || inWeex) && typeof console !== 'undefined') {
            console.error(err);
        } else {
            throw err
        }
    }

    /*  */
    /* globals MessageChannel */

    var callbacks = [];
    var pending = false;

    function flushCallbacks () {
        pending = false;
        var copies = callbacks.slice(0);
        callbacks.length = 0;
        for (var i = 0; i < copies.length; i++) {
            copies[i]();
        }
    }

// Here we have async deferring wrappers using both microtasks and (macro) tasks.
// In < 2.4 we used microtasks everywhere, but there are some scenarios where
// microtasks have too high a priority and fire in between supposedly
// sequential events (e.g. #4521, #6690) or even between bubbling of the same
// event (#6566). However, using (macro) tasks everywhere also has subtle problems
// when state is changed right before repaint (e.g. #6813, out-in transitions).
// Here we use microtask by default, but expose a way to force (macro) task when
// needed (e.g. in event handlers attached by v-on).
    var microTimerFunc;
    var macroTimerFunc;
    var useMacroTask = false;

// Determine (macro) task defer implementation.
// Technically setImmediate should be the ideal choice, but it's only available
// in IE. The only polyfill that consistently queues the callback after all DOM
// events triggered in the same loop is by using MessageChannel.
    /* istanbul ignore if */
    if (typeof setImmediate !== 'undefined' && isNative(setImmediate)) {
        macroTimerFunc = function () {
            setImmediate(flushCallbacks);
        };
    } else if (typeof MessageChannel !== 'undefined' && (
            isNative(MessageChannel) ||
            // PhantomJS
            MessageChannel.toString() === '[object MessageChannelConstructor]'
        )) {
        var channel = new MessageChannel();
        var port = channel.port2;
        channel.port1.onmessage = flushCallbacks;
        macroTimerFunc = function () {
            port.postMessage(1);
        };
    } else {
        /* istanbul ignore next */
        macroTimerFunc = function () {
            setTimeout(flushCallbacks, 0);
        };
    }

// Determine microtask defer implementation.
    /* istanbul ignore next, $flow-disable-line */
    if (typeof Promise !== 'undefined' && isNative(Promise)) {
        var p = Promise.resolve();
        microTimerFunc = function () {
            p.then(flushCallbacks);
            // in problematic UIWebViews, Promise.then doesn't completely break, but
            // it can get stuck in a weird state where callbacks are pushed into the
            // microtask queue but the queue isn't being flushed, until the browser
            // needs to do some other work, e.g. handle a timer. Therefore we can
            // "force" the microtask queue to be flushed by adding an empty timer.
            if (isIOS) { setTimeout(noop); }
        };
    } else {
        // fallback to macro
        microTimerFunc = macroTimerFunc;
    }

    /**
     * Wrap a function so that if any code inside triggers state change,
     * the changes are queued using a (macro) task instead of a microtask.
     */
    function withMacroTask (fn) {
        return fn._withTask || (fn._withTask = function () {
                useMacroTask = true;
                var res = fn.apply(null, arguments);
                useMacroTask = false;
                return res
            })
    }

    function nextTick (cb, ctx) {
        var _resolve;
        callbacks.push(function () {
            if (cb) {
                try {
                    cb.call(ctx);
                } catch (e) {
                    handleError(e, ctx, 'nextTick');
                }
            } else if (_resolve) {
                _resolve(ctx);
            }
        });
        if (!pending) {
            pending = true;
            if (useMacroTask) {
                macroTimerFunc();
            } else {
                microTimerFunc();
            }
        }
        // $flow-disable-line
        if (!cb && typeof Promise !== 'undefined') {
            return new Promise(function (resolve) {
                _resolve = resolve;
            })
        }
    }

    /*  */

    var mark;
    var measure;

    {
        var perf = inBrowser && window.performance;
        /* istanbul ignore if */
        if (
            perf &&
            perf.mark &&
            perf.measure &&
            perf.clearMarks &&
            perf.clearMeasures
        ) {
            mark = function (tag) { return perf.mark(tag); };
            measure = function (name, startTag, endTag) {
                perf.measure(name, startTag, endTag);
                perf.clearMarks(startTag);
                perf.clearMarks(endTag);
                perf.clearMeasures(name);
            };
        }
    }

    /* not type checking this file because flow doesn't play well with Proxy */

    var initProxy;

    {
        var allowedGlobals = makeMap(
            'Infinity,undefined,NaN,isFinite,isNaN,' +
            'parseFloat,parseInt,decodeURI,decodeURIComponent,encodeURI,encodeURIComponent,' +
            'Math,Number,Date,Array,Object,Boolean,String,RegExp,Map,Set,JSON,Intl,' +
            'require' // for Webpack/Browserify
        );

        var warnNonPresent = function (target, key) {
            warn(
                "Property or method \"" + key + "\" is not defined on the instance but " +
                'referenced during render. Make sure that this property is reactive, ' +
                'either in the data option, or for class-based components, by ' +
                'initializing the property. ' +
                'See: https://vuejs.org/v2/guide/reactivity.html#Declaring-Reactive-Properties.',
                target
            );
        };

        var hasProxy =
            typeof Proxy !== 'undefined' && isNative(Proxy);

        if (hasProxy) {
            var isBuiltInModifier = makeMap('stop,prevent,self,ctrl,shift,alt,meta,exact');
            config.keyCodes = new Proxy(config.keyCodes, {
                set: function set (target, key, value) {
                    if (isBuiltInModifier(key)) {
                        warn(("Avoid overwriting built-in modifier in config.keyCodes: ." + key));
                        return false
                    } else {
                        target[key] = value;
                        return true
                    }
                }
            });
        }

        var hasHandler = {
            has: function has (target, key) {
                var has = key in target;
                var isAllowed = allowedGlobals(key) || key.charAt(0) === '_';
                if (!has && !isAllowed) {
                    warnNonPresent(target, key);
                }
                return has || !isAllowed
            }
        };

        var getHandler = {
            get: function get (target, key) {
                if (typeof key === 'string' && !(key in target)) {
                    warnNonPresent(target, key);
                }
                return target[key]
            }
        };

        initProxy = function initProxy (vm) {
            if (hasProxy) {
                // determine which proxy handler to use
                var options = vm.$options;
                var handlers = options.render && options.render._withStripped
                    ? getHandler
                    : hasHandler;
                vm._renderProxy = new Proxy(vm, handlers);
            } else {
                vm._renderProxy = vm;
            }
        };
    }

    /*  */

    var seenObjects = new _Set();

    /**
     * Recursively traverse an object to evoke all converted
     * getters, so that every nested property inside the object
     * is collected as a "deep" dependency.
     */
    function traverse (val) {
        _traverse(val, seenObjects);
        seenObjects.clear();
    }

    function _traverse (val, seen) {
        var i, keys;
        var isA = Array.isArray(val);
        if ((!isA && !isObject(val)) || Object.isFrozen(val) || val instanceof VNode) {
            return
        }
        if (val.__ob__) {
            var depId = val.__ob__.dep.id;
            if (seen.has(depId)) {
                return
            }
            seen.add(depId);
        }
        if (isA) {
            i = val.length;
            while (i--) { _traverse(val[i], seen); }
        } else {
            keys = Object.keys(val);
            i = keys.length;
            while (i--) { _traverse(val[keys[i]], seen); }
        }
    }

    /*  */

    var normalizeEvent = cached(function (name) {
        var passive = name.charAt(0) === '&';
        name = passive ? name.slice(1) : name;
        var once$$1 = name.charAt(0) === '~'; // Prefixed last, checked first
        name = once$$1 ? name.slice(1) : name;
        var capture = name.charAt(0) === '!';
        name = capture ? name.slice(1) : name;
        return {
            name: name,
            once: once$$1,
            capture: capture,
            passive: passive
        }
    });

    function createFnInvoker (fns) {
        function invoker () {
            var arguments$1 = arguments;

            var fns = invoker.fns;
            if (Array.isArray(fns)) {
                var cloned = fns.slice();
                for (var i = 0; i < cloned.length; i++) {
                    cloned[i].apply(null, arguments$1);
                }
            } else {
                // return handler return value for single handlers
                return fns.apply(null, arguments)
            }
        }
        invoker.fns = fns;
        return invoker
    }

    function updateListeners (
        on,
        oldOn,
        add,
        remove$$1,
        vm
    ) {
        var name, def, cur, old, event;
        for (name in on) {
            def = cur = on[name];
            old = oldOn[name];
            event = normalizeEvent(name);
            /* istanbul ignore if */
            if (isUndef(cur)) {
                "development" !== 'production' && warn(
                    "Invalid handler for event \"" + (event.name) + "\": got " + String(cur),
                    vm
                );
            } else if (isUndef(old)) {
                if (isUndef(cur.fns)) {
                    cur = on[name] = createFnInvoker(cur);
                }
                add(event.name, cur, event.once, event.capture, event.passive, event.params);
            } else if (cur !== old) {
                old.fns = cur;
                on[name] = old;
            }
        }
        for (name in oldOn) {
            if (isUndef(on[name])) {
                event = normalizeEvent(name);
                remove$$1(event.name, oldOn[name], event.capture);
            }
        }
    }

    /*  */

    function mergeVNodeHook (def, hookKey, hook) {
        if (def instanceof VNode) {
            def = def.data.hook || (def.data.hook = {});
        }
        var invoker;
        var oldHook = def[hookKey];

        function wrappedHook () {
            hook.apply(this, arguments);
            // important: remove merged hook to ensure it's called only once
            // and prevent memory leak
            remove(invoker.fns, wrappedHook);
        }

        if (isUndef(oldHook)) {
            // no existing hook
            invoker = createFnInvoker([wrappedHook]);
        } else {
            /* istanbul ignore if */
            if (isDef(oldHook.fns) && isTrue(oldHook.merged)) {
                // already a merged invoker
                invoker = oldHook;
                invoker.fns.push(wrappedHook);
            } else {
                // existing plain hook
                invoker = createFnInvoker([oldHook, wrappedHook]);
            }
        }

        invoker.merged = true;
        def[hookKey] = invoker;
    }

    /*  */

    function extractPropsFromVNodeData (
        data,
        Ctor,
        tag
    ) {
        // we are only extracting raw values here.
        // validation and default values are handled in the child
        // component itself.
        var propOptions = Ctor.options.props;
        if (isUndef(propOptions)) {
            return
        }
        var res = {};
        var attrs = data.attrs;
        var props = data.props;
        if (isDef(attrs) || isDef(props)) {
            for (var key in propOptions) {
                var altKey = hyphenate(key);
                {
                    var keyInLowerCase = key.toLowerCase();
                    if (
                        key !== keyInLowerCase &&
                        attrs && hasOwn(attrs, keyInLowerCase)
                    ) {
                        tip(
                            "Prop \"" + keyInLowerCase + "\" is passed to component " +
                            (formatComponentName(tag || Ctor)) + ", but the declared prop name is" +
                            " \"" + key + "\". " +
                            "Note that HTML attributes are case-insensitive and camelCased " +
                            "props need to use their kebab-case equivalents when using in-DOM " +
                            "templates. You should probably use \"" + altKey + "\" instead of \"" + key + "\"."
                        );
                    }
                }
                checkProp(res, props, key, altKey, true) ||
                checkProp(res, attrs, key, altKey, false);
            }
        }
        return res
    }

    function checkProp (
        res,
        hash,
        key,
        altKey,
        preserve
    ) {
        if (isDef(hash)) {
            if (hasOwn(hash, key)) {
                res[key] = hash[key];
                if (!preserve) {
                    delete hash[key];
                }
                return true
            } else if (hasOwn(hash, altKey)) {
                res[key] = hash[altKey];
                if (!preserve) {
                    delete hash[altKey];
                }
                return true
            }
        }
        return false
    }

    /*  */

// The template compiler attempts to minimize the need for normalization by
// statically analyzing the template at compile time.
//
// For plain HTML markup, normalization can be completely skipped because the
// generated render function is guaranteed to return Array<VNode>. There are
// two cases where extra normalization is needed:

// 1. When the children contains components - because a functional component
// may return an Array instead of a single root. In this case, just a simple
// normalization is needed - if any child is an Array, we flatten the whole
// thing with Array.prototype.concat. It is guaranteed to be only 1-level deep
// because functional components already normalize their own children.
    function simpleNormalizeChildren (children) {
        for (var i = 0; i < children.length; i++) {
            if (Array.isArray(children[i])) {
                return Array.prototype.concat.apply([], children)
            }
        }
        return children
    }

// 2. When the children contains constructs that always generated nested Arrays,
// e.g. <template>, <slot>, v-for, or when the children is provided by user
// with hand-written render functions / JSX. In such cases a full normalization
// is needed to cater to all possible types of children values.
    function normalizeChildren (children) {
        return isPrimitive(children)
            ? [createTextVNode(children)]
            : Array.isArray(children)
            ? normalizeArrayChildren(children)
            : undefined
    }

    function isTextNode (node) {
        return isDef(node) && isDef(node.text) && isFalse(node.isComment)
    }

    function normalizeArrayChildren (children, nestedIndex) {
        var res = [];
        var i, c, lastIndex, last;
        for (i = 0; i < children.length; i++) {
            c = children[i];
            if (isUndef(c) || typeof c === 'boolean') { continue }
            lastIndex = res.length - 1;
            last = res[lastIndex];
            //  nested
            if (Array.isArray(c)) {
                if (c.length > 0) {
                    c = normalizeArrayChildren(c, ((nestedIndex || '') + "_" + i));
                    // merge adjacent text nodes
                    if (isTextNode(c[0]) && isTextNode(last)) {
                        res[lastIndex] = createTextVNode(last.text + (c[0]).text);
                        c.shift();
                    }
                    res.push.apply(res, c);
                }
            } else if (isPrimitive(c)) {
                if (isTextNode(last)) {
                    // merge adjacent text nodes
                    // this is necessary for SSR hydration because text nodes are
                    // essentially merged when rendered to HTML strings
                    res[lastIndex] = createTextVNode(last.text + c);
                } else if (c !== '') {
                    // convert primitive to vnode
                    res.push(createTextVNode(c));
                }
            } else {
                if (isTextNode(c) && isTextNode(last)) {
                    // merge adjacent text nodes
                    res[lastIndex] = createTextVNode(last.text + c.text);
                } else {
                    // default key for nested array children (likely generated by v-for)
                    if (isTrue(children._isVList) &&
                        isDef(c.tag) &&
                        isUndef(c.key) &&
                        isDef(nestedIndex)) {
                        c.key = "__vlist" + nestedIndex + "_" + i + "__";
                    }
                    res.push(c);
                }
            }
        }
        return res
    }

    /*  */

    function ensureCtor (comp, base) {
        if (
            comp.__esModule ||
            (hasSymbol && comp[Symbol.toStringTag] === 'Module')
        ) {
            comp = comp.default;
        }
        return isObject(comp)
            ? base.extend(comp)
            : comp
    }

    function createAsyncPlaceholder (
        factory,
        data,
        context,
        children,
        tag
    ) {
        var node = createEmptyVNode();
        node.asyncFactory = factory;
        node.asyncMeta = { data: data, context: context, children: children, tag: tag };
        return node
    }

    function resolveAsyncComponent (
        factory,
        baseCtor,
        context
    ) {
        if (isTrue(factory.error) && isDef(factory.errorComp)) {
            return factory.errorComp
        }

        if (isDef(factory.resolved)) {
            return factory.resolved
        }

        if (isTrue(factory.loading) && isDef(factory.loadingComp)) {
            return factory.loadingComp
        }

        if (isDef(factory.contexts)) {
            // already pending
            factory.contexts.push(context);
        } else {
            var contexts = factory.contexts = [context];
            var sync = true;

            var forceRender = function () {
                for (var i = 0, l = contexts.length; i < l; i++) {
                    contexts[i].$forceUpdate();
                }
            };

            var resolve = once(function (res) {
                // cache resolved
                factory.resolved = ensureCtor(res, baseCtor);
                // invoke callbacks only if this is not a synchronous resolve
                // (async resolves are shimmed as synchronous during SSR)
                if (!sync) {
                    forceRender();
                }
            });

            var reject = once(function (reason) {
                "development" !== 'production' && warn(
                    "Failed to resolve async component: " + (String(factory)) +
                    (reason ? ("\nReason: " + reason) : '')
                );
                if (isDef(factory.errorComp)) {
                    factory.error = true;
                    forceRender();
                }
            });

            var res = factory(resolve, reject);

            if (isObject(res)) {
                if (typeof res.then === 'function') {
                    // () => Promise
                    if (isUndef(factory.resolved)) {
                        res.then(resolve, reject);
                    }
                } else if (isDef(res.component) && typeof res.component.then === 'function') {
                    res.component.then(resolve, reject);

                    if (isDef(res.error)) {
                        factory.errorComp = ensureCtor(res.error, baseCtor);
                    }

                    if (isDef(res.loading)) {
                        factory.loadingComp = ensureCtor(res.loading, baseCtor);
                        if (res.delay === 0) {
                            factory.loading = true;
                        } else {
                            setTimeout(function () {
                                if (isUndef(factory.resolved) && isUndef(factory.error)) {
                                    factory.loading = true;
                                    forceRender();
                                }
                            }, res.delay || 200);
                        }
                    }

                    if (isDef(res.timeout)) {
                        setTimeout(function () {
                            if (isUndef(factory.resolved)) {
                                reject(
                                    "timeout (" + (res.timeout) + "ms)"
                                );
                            }
                        }, res.timeout);
                    }
                }
            }

            sync = false;
            // return in case resolved synchronously
            return factory.loading
                ? factory.loadingComp
                : factory.resolved
        }
    }

    /*  */

    function isAsyncPlaceholder (node) {
        return node.isComment && node.asyncFactory
    }

    /*  */

    function getFirstComponentChild (children) {
        if (Array.isArray(children)) {
            for (var i = 0; i < children.length; i++) {
                var c = children[i];
                if (isDef(c) && (isDef(c.componentOptions) || isAsyncPlaceholder(c))) {
                    return c
                }
            }
        }
    }

    /*  */

    /*  */

    function initEvents (vm) {
        vm._events = Object.create(null);
        vm._hasHookEvent = false;
        // init parent attached events
        var listeners = vm.$options._parentListeners;
        if (listeners) {
            updateComponentListeners(vm, listeners);
        }
    }

    var target;

    function add (event, fn, once) {
        if (once) {
            target.$once(event, fn);
        } else {
            target.$on(event, fn);
        }
    }

    function remove$1 (event, fn) {
        target.$off(event, fn);
    }

    function updateComponentListeners (
        vm,
        listeners,
        oldListeners
    ) {
        target = vm;
        updateListeners(listeners, oldListeners || {}, add, remove$1, vm);
        target = undefined;
    }

    function eventsMixin (Vue) {
        var hookRE = /^hook:/;
        Vue.prototype.$on = function (event, fn) {
            var this$1 = this;

            var vm = this;
            if (Array.isArray(event)) {
                for (var i = 0, l = event.length; i < l; i++) {
                    this$1.$on(event[i], fn);
                }
            } else {
                (vm._events[event] || (vm._events[event] = [])).push(fn);
                // optimize hook:event cost by using a boolean flag marked at registration
                // instead of a hash lookup
                if (hookRE.test(event)) {
                    vm._hasHookEvent = true;
                }
            }
            return vm
        };

        Vue.prototype.$once = function (event, fn) {
            var vm = this;
            function on () {
                vm.$off(event, on);
                fn.apply(vm, arguments);
            }
            on.fn = fn;
            vm.$on(event, on);
            return vm
        };

        Vue.prototype.$off = function (event, fn) {
            var this$1 = this;

            var vm = this;
            // all
            if (!arguments.length) {
                vm._events = Object.create(null);
                return vm
            }
            // array of events
            if (Array.isArray(event)) {
                for (var i = 0, l = event.length; i < l; i++) {
                    this$1.$off(event[i], fn);
                }
                return vm
            }
            // specific event
            var cbs = vm._events[event];
            if (!cbs) {
                return vm
            }
            if (!fn) {
                vm._events[event] = null;
                return vm
            }
            if (fn) {
                // specific handler
                var cb;
                var i$1 = cbs.length;
                while (i$1--) {
                    cb = cbs[i$1];
                    if (cb === fn || cb.fn === fn) {
                        cbs.splice(i$1, 1);
                        break
                    }
                }
            }
            return vm
        };

        Vue.prototype.$emit = function (event) {
            var vm = this;
            {
                var lowerCaseEvent = event.toLowerCase();
                if (lowerCaseEvent !== event && vm._events[lowerCaseEvent]) {
                    tip(
                        "Event \"" + lowerCaseEvent + "\" is emitted in component " +
                        (formatComponentName(vm)) + " but the handler is registered for \"" + event + "\". " +
                        "Note that HTML attributes are case-insensitive and you cannot use " +
                        "v-on to listen to camelCase events when using in-DOM templates. " +
                        "You should probably use \"" + (hyphenate(event)) + "\" instead of \"" + event + "\"."
                    );
                }
            }
            var cbs = vm._events[event];
            if (cbs) {
                cbs = cbs.length > 1 ? toArray(cbs) : cbs;
                var args = toArray(arguments, 1);
                for (var i = 0, l = cbs.length; i < l; i++) {
                    try {
                        cbs[i].apply(vm, args);
                    } catch (e) {
                        handleError(e, vm, ("event handler for \"" + event + "\""));
                    }
                }
            }
            return vm
        };
    }

    /*  */



    /**
     * Runtime helper for resolving raw children VNodes into a slot object.
     */
    function resolveSlots (
        children,
        context
    ) {
        var slots = {};
        if (!children) {
            return slots
        }
        for (var i = 0, l = children.length; i < l; i++) {
            var child = children[i];
            var data = child.data;
            // remove slot attribute if the node is resolved as a Vue slot node
            if (data && data.attrs && data.attrs.slot) {
                delete data.attrs.slot;
            }
            // named slots should only be respected if the vnode was rendered in the
            // same context.
            if ((child.context === context || child.fnContext === context) &&
                data && data.slot != null
            ) {
                var name = data.slot;
                var slot = (slots[name] || (slots[name] = []));
                if (child.tag === 'template') {
                    slot.push.apply(slot, child.children || []);
                } else {
                    slot.push(child);
                }
            } else {
                (slots.default || (slots.default = [])).push(child);
            }
        }
        // ignore slots that contains only whitespace
        for (var name$1 in slots) {
            if (slots[name$1].every(isWhitespace)) {
                delete slots[name$1];
            }
        }
        return slots
    }

    function isWhitespace (node) {
        return (node.isComment && !node.asyncFactory) || node.text === ' '
    }

    function resolveScopedSlots (
        fns, // see flow/vnode
        res
    ) {
        res = res || {};
        for (var i = 0; i < fns.length; i++) {
            if (Array.isArray(fns[i])) {
                resolveScopedSlots(fns[i], res);
            } else {
                res[fns[i].key] = fns[i].fn;
            }
        }
        return res
    }

    /*  */

    var activeInstance = null;
    var isUpdatingChildComponent = false;

    function initLifecycle (vm) {
        var options = vm.$options;

        // locate first non-abstract parent
        var parent = options.parent;
        if (parent && !options.abstract) {
            while (parent.$options.abstract && parent.$parent) {
                parent = parent.$parent;
            }
            parent.$children.push(vm);
        }

        vm.$parent = parent;
        vm.$root = parent ? parent.$root : vm;

        vm.$children = [];
        vm.$refs = {};

        vm._watcher = null;
        vm._inactive = null;
        vm._directInactive = false;
        vm._isMounted = false;
        vm._isDestroyed = false;
        vm._isBeingDestroyed = false;
    }

    function lifecycleMixin (Vue) {
        Vue.prototype._update = function (vnode, hydrating) {
            var vm = this;
            if (vm._isMounted) {
                callHook(vm, 'beforeUpdate');
            }
            var prevEl = vm.$el;
            var prevVnode = vm._vnode;
            var prevActiveInstance = activeInstance;
            activeInstance = vm;
            vm._vnode = vnode;
            // Vue.prototype.__patch__ is injected in entry points
            // based on the rendering backend used.
            if (!prevVnode) {
                // initial render
                vm.$el = vm.__patch__(
                    vm.$el, vnode, hydrating, false /* removeOnly */,
                    vm.$options._parentElm,
                    vm.$options._refElm
                );
                // no need for the ref nodes after initial patch
                // this prevents keeping a detached DOM tree in memory (#5851)
                vm.$options._parentElm = vm.$options._refElm = null;
            } else {
                // updates
                vm.$el = vm.__patch__(prevVnode, vnode);
            }
            activeInstance = prevActiveInstance;
            // update __vue__ reference
            if (prevEl) {
                prevEl.__vue__ = null;
            }
            if (vm.$el) {
                vm.$el.__vue__ = vm;
            }
            // if parent is an HOC, update its $el as well
            if (vm.$vnode && vm.$parent && vm.$vnode === vm.$parent._vnode) {
                vm.$parent.$el = vm.$el;
            }
            // updated hook is called by the scheduler to ensure that children are
            // updated in a parent's updated hook.
        };

        Vue.prototype.$forceUpdate = function () {
            var vm = this;
            if (vm._watcher) {
                vm._watcher.update();
            }
        };

        Vue.prototype.$destroy = function () {
            var vm = this;
            if (vm._isBeingDestroyed) {
                return
            }
            callHook(vm, 'beforeDestroy');
            vm._isBeingDestroyed = true;
            // remove self from parent
            var parent = vm.$parent;
            if (parent && !parent._isBeingDestroyed && !vm.$options.abstract) {
                remove(parent.$children, vm);
            }
            // teardown watchers
            if (vm._watcher) {
                vm._watcher.teardown();
            }
            var i = vm._watchers.length;
            while (i--) {
                vm._watchers[i].teardown();
            }
            // remove reference from data ob
            // frozen object may not have observer.
            if (vm._data.__ob__) {
                vm._data.__ob__.vmCount--;
            }
            // call the last hook...
            vm._isDestroyed = true;
            // invoke destroy hooks on current rendered tree
            vm.__patch__(vm._vnode, null);
            // fire destroyed hook
            callHook(vm, 'destroyed');
            // turn off all instance listeners.
            vm.$off();
            // remove __vue__ reference
            if (vm.$el) {
                vm.$el.__vue__ = null;
            }
            // release circular reference (#6759)
            if (vm.$vnode) {
                vm.$vnode.parent = null;
            }
        };
    }

    function mountComponent (
        vm,
        el,
        hydrating
    ) {
        vm.$el = el;
        if (!vm.$options.render) {
            vm.$options.render = createEmptyVNode;
            {
                /* istanbul ignore if */
                if ((vm.$options.template && vm.$options.template.charAt(0) !== '#') ||
                    vm.$options.el || el) {
                    warn(
                        'You are using the runtime-only build of Vue where the template ' +
                        'compiler is not available. Either pre-compile the templates into ' +
                        'render functions, or use the compiler-included build.',
                        vm
                    );
                } else {
                    warn(
                        'Failed to mount component: template or render function not defined.',
                        vm
                    );
                }
            }
        }
        callHook(vm, 'beforeMount');

        var updateComponent;
        /* istanbul ignore if */
        if ("development" !== 'production' && config.performance && mark) {
            updateComponent = function () {
                var name = vm._name;
                var id = vm._uid;
                var startTag = "vue-perf-start:" + id;
                var endTag = "vue-perf-end:" + id;

                mark(startTag);
                var vnode = vm._render();
                mark(endTag);
                measure(("vue " + name + " render"), startTag, endTag);

                mark(startTag);
                vm._update(vnode, hydrating);
                mark(endTag);
                measure(("vue " + name + " patch"), startTag, endTag);
            };
        } else {
            updateComponent = function () {
                vm._update(vm._render(), hydrating);
            };
        }

        // we set this to vm._watcher inside the watcher's constructor
        // since the watcher's initial patch may call $forceUpdate (e.g. inside child
        // component's mounted hook), which relies on vm._watcher being already defined
        new Watcher(vm, updateComponent, noop, null, true /* isRenderWatcher */);
        hydrating = false;

        // manually mounted instance, call mounted on self
        // mounted is called for render-created child components in its inserted hook
        if (vm.$vnode == null) {
            vm._isMounted = true;
            callHook(vm, 'mounted');
        }
        return vm
    }

    function updateChildComponent (
        vm,
        propsData,
        listeners,
        parentVnode,
        renderChildren
    ) {
        {
            isUpdatingChildComponent = true;
        }

        // determine whether component has slot children
        // we need to do this before overwriting $options._renderChildren
        var hasChildren = !!(
            renderChildren ||               // has new static slots
            vm.$options._renderChildren ||  // has old static slots
            parentVnode.data.scopedSlots || // has new scoped slots
            vm.$scopedSlots !== emptyObject // has old scoped slots
        );

        vm.$options._parentVnode = parentVnode;
        vm.$vnode = parentVnode; // update vm's placeholder node without re-render

        if (vm._vnode) { // update child tree's parent
            vm._vnode.parent = parentVnode;
        }
        vm.$options._renderChildren = renderChildren;

        // update $attrs and $listeners hash
        // these are also reactive so they may trigger child update if the child
        // used them during render
        vm.$attrs = parentVnode.data.attrs || emptyObject;
        vm.$listeners = listeners || emptyObject;

        // update props
        if (propsData && vm.$options.props) {
            toggleObserving(false);
            var props = vm._props;
            var propKeys = vm.$options._propKeys || [];
            for (var i = 0; i < propKeys.length; i++) {
                var key = propKeys[i];
                var propOptions = vm.$options.props; // wtf flow?
                props[key] = validateProp(key, propOptions, propsData, vm);
            }
            toggleObserving(true);
            // keep a copy of raw propsData
            vm.$options.propsData = propsData;
        }

        // update listeners
        listeners = listeners || emptyObject;
        var oldListeners = vm.$options._parentListeners;
        vm.$options._parentListeners = listeners;
        updateComponentListeners(vm, listeners, oldListeners);

        // resolve slots + force update if has children
        if (hasChildren) {
            vm.$slots = resolveSlots(renderChildren, parentVnode.context);
            vm.$forceUpdate();
        }

        {
            isUpdatingChildComponent = false;
        }
    }

    function isInInactiveTree (vm) {
        while (vm && (vm = vm.$parent)) {
            if (vm._inactive) { return true }
        }
        return false
    }

    function activateChildComponent (vm, direct) {
        if (direct) {
            vm._directInactive = false;
            if (isInInactiveTree(vm)) {
                return
            }
        } else if (vm._directInactive) {
            return
        }
        if (vm._inactive || vm._inactive === null) {
            vm._inactive = false;
            for (var i = 0; i < vm.$children.length; i++) {
                activateChildComponent(vm.$children[i]);
            }
            callHook(vm, 'activated');
        }
    }

    function deactivateChildComponent (vm, direct) {
        if (direct) {
            vm._directInactive = true;
            if (isInInactiveTree(vm)) {
                return
            }
        }
        if (!vm._inactive) {
            vm._inactive = true;
            for (var i = 0; i < vm.$children.length; i++) {
                deactivateChildComponent(vm.$children[i]);
            }
            callHook(vm, 'deactivated');
        }
    }

    function callHook (vm, hook) {
        // #7573 disable dep collection when invoking lifecycle hooks
        pushTarget();
        var handlers = vm.$options[hook];
        if (handlers) {
            for (var i = 0, j = handlers.length; i < j; i++) {
                try {
                    handlers[i].call(vm);
                } catch (e) {
                    handleError(e, vm, (hook + " hook"));
                }
            }
        }
        if (vm._hasHookEvent) {
            vm.$emit('hook:' + hook);
        }
        popTarget();
    }

    /*  */


    var MAX_UPDATE_COUNT = 100;

    var queue = [];
    var activatedChildren = [];
    var has = {};
    var circular = {};
    var waiting = false;
    var flushing = false;
    var index = 0;

    /**
     * Reset the scheduler's state.
     */
    function resetSchedulerState () {
        index = queue.length = activatedChildren.length = 0;
        has = {};
        {
            circular = {};
        }
        waiting = flushing = false;
    }

    /**
     * Flush both queues and run the watchers.
     */
    function flushSchedulerQueue () {
        flushing = true;
        var watcher, id;

        // Sort queue before flush.
        // This ensures that:
        // 1. Components are updated from parent to child. (because parent is always
        //    created before the child)
        // 2. A component's user watchers are run before its render watcher (because
        //    user watchers are created before the render watcher)
        // 3. If a component is destroyed during a parent component's watcher run,
        //    its watchers can be skipped.
        queue.sort(function (a, b) { return a.id - b.id; });

        // do not cache length because more watchers might be pushed
        // as we run existing watchers
        for (index = 0; index < queue.length; index++) {
            watcher = queue[index];
            id = watcher.id;
            has[id] = null;
            watcher.run();
            // in dev build, check and stop circular updates.
            if ("development" !== 'production' && has[id] != null) {
                circular[id] = (circular[id] || 0) + 1;
                if (circular[id] > MAX_UPDATE_COUNT) {
                    warn(
                        'You may have an infinite update loop ' + (
                            watcher.user
                                ? ("in watcher with expression \"" + (watcher.expression) + "\"")
                                : "in a component render function."
                        ),
                        watcher.vm
                    );
                    break
                }
            }
        }

        // keep copies of post queues before resetting state
        var activatedQueue = activatedChildren.slice();
        var updatedQueue = queue.slice();

        resetSchedulerState();

        // call component updated and activated hooks
        callActivatedHooks(activatedQueue);
        callUpdatedHooks(updatedQueue);

        // devtool hook
        /* istanbul ignore if */
        if (devtools && config.devtools) {
            devtools.emit('flush');
        }
    }

    function callUpdatedHooks (queue) {
        var i = queue.length;
        while (i--) {
            var watcher = queue[i];
            var vm = watcher.vm;
            if (vm._watcher === watcher && vm._isMounted) {
                callHook(vm, 'updated');
            }
        }
    }

    /**
     * Queue a kept-alive component that was activated during patch.
     * The queue will be processed after the entire tree has been patched.
     */
    function queueActivatedComponent (vm) {
        // setting _inactive to false here so that a render function can
        // rely on checking whether it's in an inactive tree (e.g. router-view)
        vm._inactive = false;
        activatedChildren.push(vm);
    }

    function callActivatedHooks (queue) {
        for (var i = 0; i < queue.length; i++) {
            queue[i]._inactive = true;
            activateChildComponent(queue[i], true /* true */);
        }
    }

    /**
     * Push a watcher into the watcher queue.
     * Jobs with duplicate IDs will be skipped unless it's
     * pushed when the queue is being flushed.
     */
    function queueWatcher (watcher) {
        var id = watcher.id;
        if (has[id] == null) {
            has[id] = true;
            if (!flushing) {
                queue.push(watcher);
            } else {
                // if already flushing, splice the watcher based on its id
                // if already past its id, it will be run next immediately.
                var i = queue.length - 1;
                while (i > index && queue[i].id > watcher.id) {
                    i--;
                }
                queue.splice(i + 1, 0, watcher);
            }
            // queue the flush
            if (!waiting) {
                waiting = true;
                nextTick(flushSchedulerQueue);
            }
        }
    }

    /*  */

    var uid$1 = 0;

    /**
     * A watcher parses an expression, collects dependencies,
     * and fires callback when the expression value changes.
     * This is used for both the $watch() api and directives.
     */
    var Watcher = function Watcher (
        vm,
        expOrFn,
        cb,
        options,
        isRenderWatcher
    ) {
        this.vm = vm;
        if (isRenderWatcher) {
            vm._watcher = this;
        }
        vm._watchers.push(this);
        // options
        if (options) {
            this.deep = !!options.deep;
            this.user = !!options.user;
            this.lazy = !!options.lazy;
            this.sync = !!options.sync;
        } else {
            this.deep = this.user = this.lazy = this.sync = false;
        }
        this.cb = cb;
        this.id = ++uid$1; // uid for batching
        this.active = true;
        this.dirty = this.lazy; // for lazy watchers
        this.deps = [];
        this.newDeps = [];
        this.depIds = new _Set();
        this.newDepIds = new _Set();
        this.expression = expOrFn.toString();
        // parse expression for getter
        if (typeof expOrFn === 'function') {
            this.getter = expOrFn;
        } else {
            this.getter = parsePath(expOrFn);
            if (!this.getter) {
                this.getter = function () {};
                "development" !== 'production' && warn(
                    "Failed watching path: \"" + expOrFn + "\" " +
                    'Watcher only accepts simple dot-delimited paths. ' +
                    'For full control, use a function instead.',
                    vm
                );
            }
        }
        this.value = this.lazy
            ? undefined
            : this.get();
    };

    /**
     * Evaluate the getter, and re-collect dependencies.
     */
    Watcher.prototype.get = function get () {
        pushTarget(this);
        var value;
        var vm = this.vm;
        try {
            value = this.getter.call(vm, vm);
        } catch (e) {
            if (this.user) {
                handleError(e, vm, ("getter for watcher \"" + (this.expression) + "\""));
            } else {
                throw e
            }
        } finally {
            // "touch" every property so they are all tracked as
            // dependencies for deep watching
            if (this.deep) {
                traverse(value);
            }
            popTarget();
            this.cleanupDeps();
        }
        return value
    };

    /**
     * Add a dependency to this directive.
     */
    Watcher.prototype.addDep = function addDep (dep) {
        var id = dep.id;
        if (!this.newDepIds.has(id)) {
            this.newDepIds.add(id);
            this.newDeps.push(dep);
            if (!this.depIds.has(id)) {
                dep.addSub(this);
            }
        }
    };

    /**
     * Clean up for dependency collection.
     */
    Watcher.prototype.cleanupDeps = function cleanupDeps () {
        var this$1 = this;

        var i = this.deps.length;
        while (i--) {
            var dep = this$1.deps[i];
            if (!this$1.newDepIds.has(dep.id)) {
                dep.removeSub(this$1);
            }
        }
        var tmp = this.depIds;
        this.depIds = this.newDepIds;
        this.newDepIds = tmp;
        this.newDepIds.clear();
        tmp = this.deps;
        this.deps = this.newDeps;
        this.newDeps = tmp;
        this.newDeps.length = 0;
    };

    /**
     * Subscriber interface.
     * Will be called when a dependency changes.
     */
    Watcher.prototype.update = function update () {
        /* istanbul ignore else */
        if (this.lazy) {
            this.dirty = true;
        } else if (this.sync) {
            this.run();
        } else {
            queueWatcher(this);
        }
    };

    /**
     * Scheduler job interface.
     * Will be called by the scheduler.
     */
    Watcher.prototype.run = function run () {
        if (this.active) {
            var value = this.get();
            if (
                value !== this.value ||
                // Deep watchers and watchers on Object/Arrays should fire even
                // when the value is the same, because the value may
                // have mutated.
                isObject(value) ||
                this.deep
            ) {
                // set new value
                var oldValue = this.value;
                this.value = value;
                if (this.user) {
                    try {
                        this.cb.call(this.vm, value, oldValue);
                    } catch (e) {
                        handleError(e, this.vm, ("callback for watcher \"" + (this.expression) + "\""));
                    }
                } else {
                    this.cb.call(this.vm, value, oldValue);
                }
            }
        }
    };

    /**
     * Evaluate the value of the watcher.
     * This only gets called for lazy watchers.
     */
    Watcher.prototype.evaluate = function evaluate () {
        this.value = this.get();
        this.dirty = false;
    };

    /**
     * Depend on all deps collected by this watcher.
     */
    Watcher.prototype.depend = function depend () {
        var this$1 = this;

        var i = this.deps.length;
        while (i--) {
            this$1.deps[i].depend();
        }
    };

    /**
     * Remove self from all dependencies' subscriber list.
     */
    Watcher.prototype.teardown = function teardown () {
        var this$1 = this;

        if (this.active) {
            // remove self from vm's watcher list
            // this is a somewhat expensive operation so we skip it
            // if the vm is being destroyed.
            if (!this.vm._isBeingDestroyed) {
                remove(this.vm._watchers, this);
            }
            var i = this.deps.length;
            while (i--) {
                this$1.deps[i].removeSub(this$1);
            }
            this.active = false;
        }
    };

    /*  */

    var sharedPropertyDefinition = {
        enumerable: true,
        configurable: true,
        get: noop,
        set: noop
    };

    function proxy (target, sourceKey, key) {
        sharedPropertyDefinition.get = function proxyGetter () {
            return this[sourceKey][key]
        };
        sharedPropertyDefinition.set = function proxySetter (val) {
            this[sourceKey][key] = val;
        };
        Object.defineProperty(target, key, sharedPropertyDefinition);
    }

    function initState (vm) {
        vm._watchers = [];
        var opts = vm.$options;
        if (opts.props) { initProps(vm, opts.props); }
        if (opts.methods) { initMethods(vm, opts.methods); }
        if (opts.data) {
            initData(vm);
        } else {
            observe(vm._data = {}, true /* asRootData */);
        }
        if (opts.computed) { initComputed(vm, opts.computed); }
        if (opts.watch && opts.watch !== nativeWatch) {
            initWatch(vm, opts.watch);
        }
    }

    function initProps (vm, propsOptions) {
        var propsData = vm.$options.propsData || {};
        var props = vm._props = {};
        // cache prop keys so that future props updates can iterate using Array
        // instead of dynamic object key enumeration.
        var keys = vm.$options._propKeys = [];
        var isRoot = !vm.$parent;
        // root instance props should be converted
        if (!isRoot) {
            toggleObserving(false);
        }
        var loop = function ( key ) {
            keys.push(key);
            var value = validateProp(key, propsOptions, propsData, vm);
            /* istanbul ignore else */
            {
                var hyphenatedKey = hyphenate(key);
                if (isReservedAttribute(hyphenatedKey) ||
                    config.isReservedAttr(hyphenatedKey)) {
                    warn(
                        ("\"" + hyphenatedKey + "\" is a reserved attribute and cannot be used as component prop."),
                        vm
                    );
                }
                defineReactive(props, key, value, function () {
                    if (vm.$parent && !isUpdatingChildComponent) {
                        warn(
                            "Avoid mutating a prop directly since the value will be " +
                            "overwritten whenever the parent component re-renders. " +
                            "Instead, use a data or computed property based on the prop's " +
                            "value. Prop being mutated: \"" + key + "\"",
                            vm
                        );
                    }
                });
            }
            // static props are already proxied on the component's prototype
            // during Vue.extend(). We only need to proxy props defined at
            // instantiation here.
            if (!(key in vm)) {
                proxy(vm, "_props", key);
            }
        };

        for (var key in propsOptions) loop( key );
        toggleObserving(true);
    }

    function initData (vm) {
        var data = vm.$options.data;
        data = vm._data = typeof data === 'function'
            ? getData(data, vm)
            : data || {};
        if (!isPlainObject(data)) {
            data = {};
            "development" !== 'production' && warn(
                'data functions should return an object:\n' +
                'https://vuejs.org/v2/guide/components.html#data-Must-Be-a-Function',
                vm
            );
        }
        // proxy data on instance
        var keys = Object.keys(data);
        var props = vm.$options.props;
        var methods = vm.$options.methods;
        var i = keys.length;
        while (i--) {
            var key = keys[i];
            {
                if (methods && hasOwn(methods, key)) {
                    warn(
                        ("Method \"" + key + "\" has already been defined as a data property."),
                        vm
                    );
                }
            }
            if (props && hasOwn(props, key)) {
                "development" !== 'production' && warn(
                    "The data property \"" + key + "\" is already declared as a prop. " +
                    "Use prop default value instead.",
                    vm
                );
            } else if (!isReserved(key)) {
                proxy(vm, "_data", key);
            }
        }
        // observe data
        observe(data, true /* asRootData */);
    }

    function getData (data, vm) {
        // #7573 disable dep collection when invoking data getters
        pushTarget();
        try {
            return data.call(vm, vm)
        } catch (e) {
            handleError(e, vm, "data()");
            return {}
        } finally {
            popTarget();
        }
    }

    var computedWatcherOptions = { lazy: true };

    function initComputed (vm, computed) {
        // $flow-disable-line
        var watchers = vm._computedWatchers = Object.create(null);
        // computed properties are just getters during SSR
        var isSSR = isServerRendering();

        for (var key in computed) {
            var userDef = computed[key];
            var getter = typeof userDef === 'function' ? userDef : userDef.get;
            if ("development" !== 'production' && getter == null) {
                warn(
                    ("Getter is missing for computed property \"" + key + "\"."),
                    vm
                );
            }

            if (!isSSR) {
                // create internal watcher for the computed property.
                watchers[key] = new Watcher(
                    vm,
                    getter || noop,
                    noop,
                    computedWatcherOptions
                );
            }

            // component-defined computed properties are already defined on the
            // component prototype. We only need to define computed properties defined
            // at instantiation here.
            if (!(key in vm)) {
                defineComputed(vm, key, userDef);
            } else {
                if (key in vm.$data) {
                    warn(("The computed property \"" + key + "\" is already defined in data."), vm);
                } else if (vm.$options.props && key in vm.$options.props) {
                    warn(("The computed property \"" + key + "\" is already defined as a prop."), vm);
                }
            }
        }
    }

    function defineComputed (
        target,
        key,
        userDef
    ) {
        var shouldCache = !isServerRendering();
        if (typeof userDef === 'function') {
            sharedPropertyDefinition.get = shouldCache
                ? createComputedGetter(key)
                : userDef;
            sharedPropertyDefinition.set = noop;
        } else {
            sharedPropertyDefinition.get = userDef.get
                ? shouldCache && userDef.cache !== false
                ? createComputedGetter(key)
                : userDef.get
                : noop;
            sharedPropertyDefinition.set = userDef.set
                ? userDef.set
                : noop;
        }
        if ("development" !== 'production' &&
            sharedPropertyDefinition.set === noop) {
            sharedPropertyDefinition.set = function () {
                warn(
                    ("Computed property \"" + key + "\" was assigned to but it has no setter."),
                    this
                );
            };
        }
        Object.defineProperty(target, key, sharedPropertyDefinition);
    }

    function createComputedGetter (key) {
        return function computedGetter () {
            var watcher = this._computedWatchers && this._computedWatchers[key];
            if (watcher) {
                if (watcher.dirty) {
                    watcher.evaluate();
                }
                if (Dep.target) {
                    watcher.depend();
                }
                return watcher.value
            }
        }
    }

    function initMethods (vm, methods) {
        var props = vm.$options.props;
        for (var key in methods) {
            {
                if (methods[key] == null) {
                    warn(
                        "Method \"" + key + "\" has an undefined value in the component definition. " +
                        "Did you reference the function correctly?",
                        vm
                    );
                }
                if (props && hasOwn(props, key)) {
                    warn(
                        ("Method \"" + key + "\" has already been defined as a prop."),
                        vm
                    );
                }
                if ((key in vm) && isReserved(key)) {
                    warn(
                        "Method \"" + key + "\" conflicts with an existing Vue instance method. " +
                        "Avoid defining component methods that start with _ or $."
                    );
                }
            }
            vm[key] = methods[key] == null ? noop : bind(methods[key], vm);
        }
    }

    function initWatch (vm, watch) {
        for (var key in watch) {
            var handler = watch[key];
            if (Array.isArray(handler)) {
                for (var i = 0; i < handler.length; i++) {
                    createWatcher(vm, key, handler[i]);
                }
            } else {
                createWatcher(vm, key, handler);
            }
        }
    }

    function createWatcher (
        vm,
        expOrFn,
        handler,
        options
    ) {
        if (isPlainObject(handler)) {
            options = handler;
            handler = handler.handler;
        }
        if (typeof handler === 'string') {
            handler = vm[handler];
        }
        return vm.$watch(expOrFn, handler, options)
    }

    function stateMixin (Vue) {
        // flow somehow has problems with directly declared definition object
        // when using Object.defineProperty, so we have to procedurally build up
        // the object here.
        var dataDef = {};
        dataDef.get = function () { return this._data };
        var propsDef = {};
        propsDef.get = function () { return this._props };
        {
            dataDef.set = function (newData) {
                warn(
                    'Avoid replacing instance root $data. ' +
                    'Use nested data properties instead.',
                    this
                );
            };
            propsDef.set = function () {
                warn("$props is readonly.", this);
            };
        }
        Object.defineProperty(Vue.prototype, '$data', dataDef);
        Object.defineProperty(Vue.prototype, '$props', propsDef);

        Vue.prototype.$set = set;
        Vue.prototype.$delete = del;

        Vue.prototype.$watch = function (
            expOrFn,
            cb,
            options
        ) {
            var vm = this;
            if (isPlainObject(cb)) {
                return createWatcher(vm, expOrFn, cb, options)
            }
            options = options || {};
            options.user = true;
            var watcher = new Watcher(vm, expOrFn, cb, options);
            if (options.immediate) {
                cb.call(vm, watcher.value);
            }
            return function unwatchFn () {
                watcher.teardown();
            }
        };
    }

    /*  */

    function initProvide (vm) {
        var provide = vm.$options.provide;
        if (provide) {
            vm._provided = typeof provide === 'function'
                ? provide.call(vm)
                : provide;
        }
    }

    function initInjections (vm) {
        var result = resolveInject(vm.$options.inject, vm);
        if (result) {
            toggleObserving(false);
            Object.keys(result).forEach(function (key) {
                /* istanbul ignore else */
                {
                    defineReactive(vm, key, result[key], function () {
                        warn(
                            "Avoid mutating an injected value directly since the changes will be " +
                            "overwritten whenever the provided component re-renders. " +
                            "injection being mutated: \"" + key + "\"",
                            vm
                        );
                    });
                }
            });
            toggleObserving(true);
        }
    }

    function resolveInject (inject, vm) {
        if (inject) {
            // inject is :any because flow is not smart enough to figure out cached
            var result = Object.create(null);
            var keys = hasSymbol
                ? Reflect.ownKeys(inject).filter(function (key) {
                /* istanbul ignore next */
                return Object.getOwnPropertyDescriptor(inject, key).enumerable
            })
                : Object.keys(inject);

            for (var i = 0; i < keys.length; i++) {
                var key = keys[i];
                var provideKey = inject[key].from;
                var source = vm;
                while (source) {
                    if (source._provided && hasOwn(source._provided, provideKey)) {
                        result[key] = source._provided[provideKey];
                        break
                    }
                    source = source.$parent;
                }
                if (!source) {
                    if ('default' in inject[key]) {
                        var provideDefault = inject[key].default;
                        result[key] = typeof provideDefault === 'function'
                            ? provideDefault.call(vm)
                            : provideDefault;
                    } else {
                        warn(("Injection \"" + key + "\" not found"), vm);
                    }
                }
            }
            return result
        }
    }

    /*  */

    /**
     * Runtime helper for rendering v-for lists.
     */
    function renderList (
        val,
        render
    ) {
        var ret, i, l, keys, key;
        if (Array.isArray(val) || typeof val === 'string') {
            ret = new Array(val.length);
            for (i = 0, l = val.length; i < l; i++) {
                ret[i] = render(val[i], i);
            }
        } else if (typeof val === 'number') {
            ret = new Array(val);
            for (i = 0; i < val; i++) {
                ret[i] = render(i + 1, i);
            }
        } else if (isObject(val)) {
            keys = Object.keys(val);
            ret = new Array(keys.length);
            for (i = 0, l = keys.length; i < l; i++) {
                key = keys[i];
                ret[i] = render(val[key], key, i);
            }
        }
        if (isDef(ret)) {
            (ret)._isVList = true;
        }
        return ret
    }

    /*  */

    /**
     * Runtime helper for rendering <slot>
     */
    function renderSlot (
        name,
        fallback,
        props,
        bindObject
    ) {
        var scopedSlotFn = this.$scopedSlots[name];
        var nodes;
        if (scopedSlotFn) { // scoped slot
            props = props || {};
            if (bindObject) {
                if ("development" !== 'production' && !isObject(bindObject)) {
                    warn(
                        'slot v-bind without argument expects an Object',
                        this
                    );
                }
                props = extend(extend({}, bindObject), props);
            }
            nodes = scopedSlotFn(props) || fallback;
        } else {
            var slotNodes = this.$slots[name];
            // warn duplicate slot usage
            if (slotNodes) {
                if ("development" !== 'production' && slotNodes._rendered) {
                    warn(
                        "Duplicate presence of slot \"" + name + "\" found in the same render tree " +
                        "- this will likely cause render errors.",
                        this
                    );
                }
                slotNodes._rendered = true;
            }
            nodes = slotNodes || fallback;
        }

        var target = props && props.slot;
        if (target) {
            return this.$createElement('template', { slot: target }, nodes)
        } else {
            return nodes
        }
    }

    /*  */

    /**
     * Runtime helper for resolving filters
     */
    function resolveFilter (id) {
        return resolveAsset(this.$options, 'filters', id, true) || identity
    }

    /*  */

    function isKeyNotMatch (expect, actual) {
        if (Array.isArray(expect)) {
            return expect.indexOf(actual) === -1
        } else {
            return expect !== actual
        }
    }

    /**
     * Runtime helper for checking keyCodes from config.
     * exposed as Vue.prototype._k
     * passing in eventKeyName as last argument separately for backwards compat
     */
    function checkKeyCodes (
        eventKeyCode,
        key,
        builtInKeyCode,
        eventKeyName,
        builtInKeyName
    ) {
        var mappedKeyCode = config.keyCodes[key] || builtInKeyCode;
        if (builtInKeyName && eventKeyName && !config.keyCodes[key]) {
            return isKeyNotMatch(builtInKeyName, eventKeyName)
        } else if (mappedKeyCode) {
            return isKeyNotMatch(mappedKeyCode, eventKeyCode)
        } else if (eventKeyName) {
            return hyphenate(eventKeyName) !== key
        }
    }

    /*  */

    /**
     * Runtime helper for merging v-bind="object" into a VNode's data.
     */
    function bindObjectProps (
        data,
        tag,
        value,
        asProp,
        isSync
    ) {
        if (value) {
            if (!isObject(value)) {
                "development" !== 'production' && warn(
                    'v-bind without argument expects an Object or Array value',
                    this
                );
            } else {
                if (Array.isArray(value)) {
                    value = toObject(value);
                }
                var hash;
                var loop = function ( key ) {
                    if (
                        key === 'class' ||
                        key === 'style' ||
                        isReservedAttribute(key)
                    ) {
                        hash = data;
                    } else {
                        var type = data.attrs && data.attrs.type;
                        hash = asProp || config.mustUseProp(tag, type, key)
                            ? data.domProps || (data.domProps = {})
                            : data.attrs || (data.attrs = {});
                    }
                    if (!(key in hash)) {
                        hash[key] = value[key];

                        if (isSync) {
                            var on = data.on || (data.on = {});
                            on[("update:" + key)] = function ($event) {
                                value[key] = $event;
                            };
                        }
                    }
                };

                for (var key in value) loop( key );
            }
        }
        return data
    }

    /*  */

    /**
     * Runtime helper for rendering static trees.
     */
    function renderStatic (
        index,
        isInFor
    ) {
        var cached = this._staticTrees || (this._staticTrees = []);
        var tree = cached[index];
        // if has already-rendered static tree and not inside v-for,
        // we can reuse the same tree.
        if (tree && !isInFor) {
            return tree
        }
        // otherwise, render a fresh tree.
        tree = cached[index] = this.$options.staticRenderFns[index].call(
            this._renderProxy,
            null,
            this // for render fns generated for functional component templates
        );
        markStatic(tree, ("__static__" + index), false);
        return tree
    }

    /**
     * Runtime helper for v-once.
     * Effectively it means marking the node as static with a unique key.
     */
    function markOnce (
        tree,
        index,
        key
    ) {
        markStatic(tree, ("__once__" + index + (key ? ("_" + key) : "")), true);
        return tree
    }

    function markStatic (
        tree,
        key,
        isOnce
    ) {
        if (Array.isArray(tree)) {
            for (var i = 0; i < tree.length; i++) {
                if (tree[i] && typeof tree[i] !== 'string') {
                    markStaticNode(tree[i], (key + "_" + i), isOnce);
                }
            }
        } else {
            markStaticNode(tree, key, isOnce);
        }
    }

    function markStaticNode (node, key, isOnce) {
        node.isStatic = true;
        node.key = key;
        node.isOnce = isOnce;
    }

    /*  */

    function bindObjectListeners (data, value) {
        if (value) {
            if (!isPlainObject(value)) {
                "development" !== 'production' && warn(
                    'v-on without argument expects an Object value',
                    this
                );
            } else {
                var on = data.on = data.on ? extend({}, data.on) : {};
                for (var key in value) {
                    var existing = on[key];
                    var ours = value[key];
                    on[key] = existing ? [].concat(existing, ours) : ours;
                }
            }
        }
        return data
    }

    /*  */

    function installRenderHelpers (target) {
        target._o = markOnce;
        target._n = toNumber;
        target._s = toString;
        target._l = renderList;
        target._t = renderSlot;
        target._q = looseEqual;
        target._i = looseIndexOf;
        target._m = renderStatic;
        target._f = resolveFilter;
        target._k = checkKeyCodes;
        target._b = bindObjectProps;
        target._v = createTextVNode;
        target._e = createEmptyVNode;
        target._u = resolveScopedSlots;
        target._g = bindObjectListeners;
    }

    /*  */

    function FunctionalRenderContext (
        data,
        props,
        children,
        parent,
        Ctor
    ) {
        var options = Ctor.options;
        // ensure the createElement function in functional components
        // gets a unique context - this is necessary for correct named slot check
        var contextVm;
        if (hasOwn(parent, '_uid')) {
            contextVm = Object.create(parent);
            // $flow-disable-line
            contextVm._original = parent;
        } else {
            // the context vm passed in is a functional context as well.
            // in this case we want to make sure we are able to get a hold to the
            // real context instance.
            contextVm = parent;
            // $flow-disable-line
            parent = parent._original;
        }
        var isCompiled = isTrue(options._compiled);
        var needNormalization = !isCompiled;

        this.data = data;
        this.props = props;
        this.children = children;
        this.parent = parent;
        this.listeners = data.on || emptyObject;
        this.injections = resolveInject(options.inject, parent);
        this.slots = function () { return resolveSlots(children, parent); };

        // support for compiled functional template
        if (isCompiled) {
            // exposing $options for renderStatic()
            this.$options = options;
            // pre-resolve slots for renderSlot()
            this.$slots = this.slots();
            this.$scopedSlots = data.scopedSlots || emptyObject;
        }

        if (options._scopeId) {
            this._c = function (a, b, c, d) {
                var vnode = createElement(contextVm, a, b, c, d, needNormalization);
                if (vnode && !Array.isArray(vnode)) {
                    vnode.fnScopeId = options._scopeId;
                    vnode.fnContext = parent;
                }
                return vnode
            };
        } else {
            this._c = function (a, b, c, d) { return createElement(contextVm, a, b, c, d, needNormalization); };
        }
    }

    installRenderHelpers(FunctionalRenderContext.prototype);

    function createFunctionalComponent (
        Ctor,
        propsData,
        data,
        contextVm,
        children
    ) {
        var options = Ctor.options;
        var props = {};
        var propOptions = options.props;
        if (isDef(propOptions)) {
            for (var key in propOptions) {
                props[key] = validateProp(key, propOptions, propsData || emptyObject);
            }
        } else {
            if (isDef(data.attrs)) { mergeProps(props, data.attrs); }
            if (isDef(data.props)) { mergeProps(props, data.props); }
        }

        var renderContext = new FunctionalRenderContext(
            data,
            props,
            children,
            contextVm,
            Ctor
        );

        var vnode = options.render.call(null, renderContext._c, renderContext);

        if (vnode instanceof VNode) {
            return cloneAndMarkFunctionalResult(vnode, data, renderContext.parent, options)
        } else if (Array.isArray(vnode)) {
            var vnodes = normalizeChildren(vnode) || [];
            var res = new Array(vnodes.length);
            for (var i = 0; i < vnodes.length; i++) {
                res[i] = cloneAndMarkFunctionalResult(vnodes[i], data, renderContext.parent, options);
            }
            return res
        }
    }

    function cloneAndMarkFunctionalResult (vnode, data, contextVm, options) {
        // #7817 clone node before setting fnContext, otherwise if the node is reused
        // (e.g. it was from a cached normal slot) the fnContext causes named slots
        // that should not be matched to match.
        var clone = cloneVNode(vnode);
        clone.fnContext = contextVm;
        clone.fnOptions = options;
        if (data.slot) {
            (clone.data || (clone.data = {})).slot = data.slot;
        }
        return clone
    }

    function mergeProps (to, from) {
        for (var key in from) {
            to[camelize(key)] = from[key];
        }
    }

    /*  */




// Register the component hook to weex native render engine.
// The hook will be triggered by native, not javascript.


// Updates the state of the component to weex native render engine.

    /*  */

// https://github.com/Hanks10100/weex-native-directive/tree/master/component

// listening on native callback

    /*  */

    /*  */

// inline hooks to be invoked on component VNodes during patch
    var componentVNodeHooks = {
        init: function init (
            vnode,
            hydrating,
            parentElm,
            refElm
        ) {
            if (
                vnode.componentInstance &&
                !vnode.componentInstance._isDestroyed &&
                vnode.data.keepAlive
            ) {
                // kept-alive components, treat as a patch
                var mountedNode = vnode; // work around flow
                componentVNodeHooks.prepatch(mountedNode, mountedNode);
            } else {
                var child = vnode.componentInstance = createComponentInstanceForVnode(
                    vnode,
                    activeInstance,
                    parentElm,
                    refElm
                );
                child.$mount(hydrating ? vnode.elm : undefined, hydrating);
            }
        },

        prepatch: function prepatch (oldVnode, vnode) {
            var options = vnode.componentOptions;
            var child = vnode.componentInstance = oldVnode.componentInstance;
            updateChildComponent(
                child,
                options.propsData, // updated props
                options.listeners, // updated listeners
                vnode, // new parent vnode
                options.children // new children
            );
        },

        insert: function insert (vnode) {
            var context = vnode.context;
            var componentInstance = vnode.componentInstance;
            if (!componentInstance._isMounted) {
                componentInstance._isMounted = true;
                callHook(componentInstance, 'mounted');
            }
            if (vnode.data.keepAlive) {
                if (context._isMounted) {
                    // vue-router#1212
                    // During updates, a kept-alive component's child components may
                    // change, so directly walking the tree here may call activated hooks
                    // on incorrect children. Instead we push them into a queue which will
                    // be processed after the whole patch process ended.
                    queueActivatedComponent(componentInstance);
                } else {
                    activateChildComponent(componentInstance, true /* direct */);
                }
            }
        },

        destroy: function destroy (vnode) {
            var componentInstance = vnode.componentInstance;
            if (!componentInstance._isDestroyed) {
                if (!vnode.data.keepAlive) {
                    componentInstance.$destroy();
                } else {
                    deactivateChildComponent(componentInstance, true /* direct */);
                }
            }
        }
    };

    var hooksToMerge = Object.keys(componentVNodeHooks);

    function createComponent (
        Ctor,
        data,
        context,
        children,
        tag
    ) {
        if (isUndef(Ctor)) {
            return
        }

        var baseCtor = context.$options._base;

        // plain options object: turn it into a constructor
        if (isObject(Ctor)) {
            Ctor = baseCtor.extend(Ctor);
        }

        // if at this stage it's not a constructor or an async component factory,
        // reject.
        if (typeof Ctor !== 'function') {
            {
                warn(("Invalid Component definition: " + (String(Ctor))), context);
            }
            return
        }

        // async component
        var asyncFactory;
        if (isUndef(Ctor.cid)) {
            asyncFactory = Ctor;
            Ctor = resolveAsyncComponent(asyncFactory, baseCtor, context);
            if (Ctor === undefined) {
                // return a placeholder node for async component, which is rendered
                // as a comment node but preserves all the raw information for the node.
                // the information will be used for async server-rendering and hydration.
                return createAsyncPlaceholder(
                    asyncFactory,
                    data,
                    context,
                    children,
                    tag
                )
            }
        }

        data = data || {};

        // resolve constructor options in case global mixins are applied after
        // component constructor creation
        resolveConstructorOptions(Ctor);

        // transform component v-model data into props & events
        if (isDef(data.model)) {
            transformModel(Ctor.options, data);
        }

        // extract props
        var propsData = extractPropsFromVNodeData(data, Ctor, tag);

        // functional component
        if (isTrue(Ctor.options.functional)) {
            return createFunctionalComponent(Ctor, propsData, data, context, children)
        }

        // extract listeners, since these needs to be treated as
        // child component listeners instead of DOM listeners
        var listeners = data.on;
        // replace with listeners with .native modifier
        // so it gets processed during parent component patch.
        data.on = data.nativeOn;

        if (isTrue(Ctor.options.abstract)) {
            // abstract components do not keep anything
            // other than props & listeners & slot

            // work around flow
            var slot = data.slot;
            data = {};
            if (slot) {
                data.slot = slot;
            }
        }

        // install component management hooks onto the placeholder node
        installComponentHooks(data);

        // return a placeholder vnode
        var name = Ctor.options.name || tag;
        var vnode = new VNode(
            ("vue-component-" + (Ctor.cid) + (name ? ("-" + name) : '')),
            data, undefined, undefined, undefined, context,
            { Ctor: Ctor, propsData: propsData, listeners: listeners, tag: tag, children: children },
            asyncFactory
        );

        // Weex specific: invoke recycle-list optimized @render function for
        // extracting cell-slot template.
        // https://github.com/Hanks10100/weex-native-directive/tree/master/component
        /* istanbul ignore if */
        return vnode
    }

    function createComponentInstanceForVnode (
        vnode, // we know it's MountedComponentVNode but flow doesn't
        parent, // activeInstance in lifecycle state
        parentElm,
        refElm
    ) {
        var options = {
            _isComponent: true,
            parent: parent,
            _parentVnode: vnode,
            _parentElm: parentElm || null,
            _refElm: refElm || null
        };
        // check inline-template render functions
        var inlineTemplate = vnode.data.inlineTemplate;
        if (isDef(inlineTemplate)) {
            options.render = inlineTemplate.render;
            options.staticRenderFns = inlineTemplate.staticRenderFns;
        }
        return new vnode.componentOptions.Ctor(options)
    }

    function installComponentHooks (data) {
        var hooks = data.hook || (data.hook = {});
        for (var i = 0; i < hooksToMerge.length; i++) {
            var key = hooksToMerge[i];
            hooks[key] = componentVNodeHooks[key];
        }
    }

// transform component v-model info (value and callback) into
// prop and event handler respectively.
    function transformModel (options, data) {
        var prop = (options.model && options.model.prop) || 'value';
        var event = (options.model && options.model.event) || 'input';(data.props || (data.props = {}))[prop] = data.model.value;
        var on = data.on || (data.on = {});
        if (isDef(on[event])) {
            on[event] = [data.model.callback].concat(on[event]);
        } else {
            on[event] = data.model.callback;
        }
    }

    /*  */

    var SIMPLE_NORMALIZE = 1;
    var ALWAYS_NORMALIZE = 2;

// wrapper function for providing a more flexible interface
// without getting yelled at by flow
    function createElement (
        context,
        tag,
        data,
        children,
        normalizationType,
        alwaysNormalize
    ) {
        if (Array.isArray(data) || isPrimitive(data)) {
            normalizationType = children;
            children = data;
            data = undefined;
        }
        if (isTrue(alwaysNormalize)) {
            normalizationType = ALWAYS_NORMALIZE;
        }
        return _createElement(context, tag, data, children, normalizationType)
    }

    function _createElement (
        context,
        tag,
        data,
        children,
        normalizationType
    ) {
        if (isDef(data) && isDef((data).__ob__)) {
            "development" !== 'production' && warn(
                "Avoid using observed data object as vnode data: " + (JSON.stringify(data)) + "\n" +
                'Always create fresh vnode data objects in each render!',
                context
            );
            return createEmptyVNode()
        }
        // object syntax in v-bind
        if (isDef(data) && isDef(data.is)) {
            tag = data.is;
        }
        if (!tag) {
            // in case of component :is set to falsy value
            return createEmptyVNode()
        }
        // warn against non-primitive key
        if ("development" !== 'production' &&
            isDef(data) && isDef(data.key) && !isPrimitive(data.key)
        ) {
            {
                warn(
                    'Avoid using non-primitive value as key, ' +
                    'use string/number value instead.',
                    context
                );
            }
        }
        // support single function children as default scoped slot
        if (Array.isArray(children) &&
            typeof children[0] === 'function'
        ) {
            data = data || {};
            data.scopedSlots = { default: children[0] };
            children.length = 0;
        }
        if (normalizationType === ALWAYS_NORMALIZE) {
            children = normalizeChildren(children);
        } else if (normalizationType === SIMPLE_NORMALIZE) {
            children = simpleNormalizeChildren(children);
        }
        var vnode, ns;
        if (typeof tag === 'string') {
            var Ctor;
            ns = (context.$vnode && context.$vnode.ns) || config.getTagNamespace(tag);
            if (config.isReservedTag(tag)) {
                // platform built-in elements
                vnode = new VNode(
                    config.parsePlatformTagName(tag), data, children,
                    undefined, undefined, context
                );
            } else if (isDef(Ctor = resolveAsset(context.$options, 'components', tag))) {
                // component
                vnode = createComponent(Ctor, data, context, children, tag);
            } else {
                // unknown or unlisted namespaced elements
                // check at runtime because it may get assigned a namespace when its
                // parent normalizes children
                vnode = new VNode(
                    tag, data, children,
                    undefined, undefined, context
                );
            }
        } else {
            // direct component options / constructor
            vnode = createComponent(tag, data, context, children);
        }
        if (Array.isArray(vnode)) {
            return vnode
        } else if (isDef(vnode)) {
            if (isDef(ns)) { applyNS(vnode, ns); }
            if (isDef(data)) { registerDeepBindings(data); }
            return vnode
        } else {
            return createEmptyVNode()
        }
    }

    function applyNS (vnode, ns, force) {
        vnode.ns = ns;
        if (vnode.tag === 'foreignObject') {
            // use default namespace inside foreignObject
            ns = undefined;
            force = true;
        }
        if (isDef(vnode.children)) {
            for (var i = 0, l = vnode.children.length; i < l; i++) {
                var child = vnode.children[i];
                if (isDef(child.tag) && (
                    isUndef(child.ns) || (isTrue(force) && child.tag !== 'svg'))) {
                    applyNS(child, ns, force);
                }
            }
        }
    }

// ref #5318
// necessary to ensure parent re-render when deep bindings like :style and
// :class are used on slot nodes
    function registerDeepBindings (data) {
        if (isObject(data.style)) {
            traverse(data.style);
        }
        if (isObject(data.class)) {
            traverse(data.class);
        }
    }

    /*  */

    function initRender (vm) {
        vm._vnode = null; // the root of the child tree
        vm._staticTrees = null; // v-once cached trees
        var options = vm.$options;
        var parentVnode = vm.$vnode = options._parentVnode; // the placeholder node in parent tree
        var renderContext = parentVnode && parentVnode.context;
        vm.$slots = resolveSlots(options._renderChildren, renderContext);
        vm.$scopedSlots = emptyObject;
        // bind the createElement fn to this instance
        // so that we get proper render context inside it.
        // args order: tag, data, children, normalizationType, alwaysNormalize
        // internal version is used by render functions compiled from templates
        vm._c = function (a, b, c, d) { return createElement(vm, a, b, c, d, false); };
        // normalization is always applied for the public version, used in
        // user-written render functions.
        vm.$createElement = function (a, b, c, d) { return createElement(vm, a, b, c, d, true); };

        // $attrs & $listeners are exposed for easier HOC creation.
        // they need to be reactive so that HOCs using them are always updated
        var parentData = parentVnode && parentVnode.data;

        /* istanbul ignore else */
        {
            defineReactive(vm, '$attrs', parentData && parentData.attrs || emptyObject, function () {
                !isUpdatingChildComponent && warn("$attrs is readonly.", vm);
            }, true);
            defineReactive(vm, '$listeners', options._parentListeners || emptyObject, function () {
                !isUpdatingChildComponent && warn("$listeners is readonly.", vm);
            }, true);
        }
    }

    function renderMixin (Vue) {
        // install runtime convenience helpers
        installRenderHelpers(Vue.prototype);

        Vue.prototype.$nextTick = function (fn) {
            return nextTick(fn, this)
        };

        Vue.prototype._render = function () {
            var vm = this;
            var ref = vm.$options;
            var render = ref.render;
            var _parentVnode = ref._parentVnode;

            // reset _rendered flag on slots for duplicate slot check
            {
                for (var key in vm.$slots) {
                    // $flow-disable-line
                    vm.$slots[key]._rendered = false;
                }
            }

            if (_parentVnode) {
                vm.$scopedSlots = _parentVnode.data.scopedSlots || emptyObject;
            }

            // set parent vnode. this allows render functions to have access
            // to the data on the placeholder node.
            vm.$vnode = _parentVnode;
            // render self
            var vnode;
            try {
                vnode = render.call(vm._renderProxy, vm.$createElement);
            } catch (e) {
                handleError(e, vm, "render");
                // return error render result,
                // or previous vnode to prevent render error causing blank component
                /* istanbul ignore else */
                {
                    if (vm.$options.renderError) {
                        try {
                            vnode = vm.$options.renderError.call(vm._renderProxy, vm.$createElement, e);
                        } catch (e) {
                            handleError(e, vm, "renderError");
                            vnode = vm._vnode;
                        }
                    } else {
                        vnode = vm._vnode;
                    }
                }
            }
            // return empty vnode in case the render function errored out
            if (!(vnode instanceof VNode)) {
                if ("development" !== 'production' && Array.isArray(vnode)) {
                    warn(
                        'Multiple root nodes returned from render function. Render function ' +
                        'should return a single root node.',
                        vm
                    );
                }
                vnode = createEmptyVNode();
            }
            // set parent
            vnode.parent = _parentVnode;
            return vnode
        };
    }

    /*  */

    var uid$3 = 0;

    function initMixin (Vue) {
        Vue.prototype._init = function (options) {
            var vm = this;
            // a uid
            vm._uid = uid$3++;

            var startTag, endTag;
            /* istanbul ignore if */
            if ("development" !== 'production' && config.performance && mark) {
                startTag = "vue-perf-start:" + (vm._uid);
                endTag = "vue-perf-end:" + (vm._uid);
                mark(startTag);
            }

            // a flag to avoid this being observed
            vm._isVue = true;
            // merge options
            if (options && options._isComponent) {
                // optimize internal component instantiation
                // since dynamic options merging is pretty slow, and none of the
                // internal component options needs special treatment.
                initInternalComponent(vm, options);
            } else {
                vm.$options = mergeOptions(
                    resolveConstructorOptions(vm.constructor),
                    options || {},
                    vm
                );
            }
            /* istanbul ignore else */
            {
                initProxy(vm);
            }
            // expose real self
            vm._self = vm;
            initLifecycle(vm);
            initEvents(vm);
            initRender(vm);
            callHook(vm, 'beforeCreate');
            initInjections(vm); // resolve injections before data/props
            initState(vm);
            initProvide(vm); // resolve provide after data/props
            callHook(vm, 'created');

            /* istanbul ignore if */
            if ("development" !== 'production' && config.performance && mark) {
                vm._name = formatComponentName(vm, false);
                mark(endTag);
                measure(("vue " + (vm._name) + " init"), startTag, endTag);
            }

            if (vm.$options.el) {
                vm.$mount(vm.$options.el);
            }
        };
    }

    function initInternalComponent (vm, options) {
        var opts = vm.$options = Object.create(vm.constructor.options);
        // doing this because it's faster than dynamic enumeration.
        var parentVnode = options._parentVnode;
        opts.parent = options.parent;
        opts._parentVnode = parentVnode;
        opts._parentElm = options._parentElm;
        opts._refElm = options._refElm;

        var vnodeComponentOptions = parentVnode.componentOptions;
        opts.propsData = vnodeComponentOptions.propsData;
        opts._parentListeners = vnodeComponentOptions.listeners;
        opts._renderChildren = vnodeComponentOptions.children;
        opts._componentTag = vnodeComponentOptions.tag;

        if (options.render) {
            opts.render = options.render;
            opts.staticRenderFns = options.staticRenderFns;
        }
    }

    function resolveConstructorOptions (Ctor) {
        var options = Ctor.options;
        if (Ctor.super) {
            var superOptions = resolveConstructorOptions(Ctor.super);
            var cachedSuperOptions = Ctor.superOptions;
            if (superOptions !== cachedSuperOptions) {
                // super option changed,
                // need to resolve new options.
                Ctor.superOptions = superOptions;
                // check if there are any late-modified/attached options (#4976)
                var modifiedOptions = resolveModifiedOptions(Ctor);
                // update base extend options
                if (modifiedOptions) {
                    extend(Ctor.extendOptions, modifiedOptions);
                }
                options = Ctor.options = mergeOptions(superOptions, Ctor.extendOptions);
                if (options.name) {
                    options.components[options.name] = Ctor;
                }
            }
        }
        return options
    }

    function resolveModifiedOptions (Ctor) {
        var modified;
        var latest = Ctor.options;
        var extended = Ctor.extendOptions;
        var sealed = Ctor.sealedOptions;
        for (var key in latest) {
            if (latest[key] !== sealed[key]) {
                if (!modified) { modified = {}; }
                modified[key] = dedupe(latest[key], extended[key], sealed[key]);
            }
        }
        return modified
    }

    function dedupe (latest, extended, sealed) {
        // compare latest and sealed to ensure lifecycle hooks won't be duplicated
        // between merges
        if (Array.isArray(latest)) {
            var res = [];
            sealed = Array.isArray(sealed) ? sealed : [sealed];
            extended = Array.isArray(extended) ? extended : [extended];
            for (var i = 0; i < latest.length; i++) {
                // push original options and not sealed options to exclude duplicated options
                if (extended.indexOf(latest[i]) >= 0 || sealed.indexOf(latest[i]) < 0) {
                    res.push(latest[i]);
                }
            }
            return res
        } else {
            return latest
        }
    }

 

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