Vue.js/dist/vue.js

/*!
 * Vue.js v2.6.12
 * (c) 2014-2020 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 = global || self, global.Vue = factory());
}(this, function () { 'use strict';

  /*  */

  var emptyObject = Object.freeze({});

  // These helpers produce 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)
  }

  function isPromise (val) {
    return (
      isDef(val) &&
      typeof val.then === 'function' &&
      typeof val.catch === 'function'
    )
  }

  /**
   * Convert a value to a string that is actually rendered.
   */
  function toString (val) {
    return val == null
      ? ''
      : Array.isArray(val) || (isPlainObject(val) && val.toString === _toString)
        ? JSON.stringify(val, null, 2)
        : String(val)
  }

  /**
   * Convert an 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 an 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 an 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 performant enough in most browsers.
   * But removing it would mean breaking code that was able to run in
   * PhantomJS 1.x, so this must be kept for backward 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
  }

  /* eslint-disable no-unused-vars */

  /**
   * 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; };

  /* eslint-enable no-unused-vars */

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

  /**
   * Generate a string containing static keys 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 (a instanceof Date && b instanceof Date) {
          return a.getTime() === b.getTime()
        } 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
    }
  }

  /**
   * Return the first index at which a loosely equal value can be
   * found in the array (if value is a plain object, the array must
   * contain an object of the same shape), or -1 if it is not present.
   */
  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',
    'serverPrefetch'
  ];

  /*  */



  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,

    /**
     * Perform updates asynchronously. Intended to be used by Vue Test Utils
     * This will significantly reduce performance if set to false.
     */
    async: true,

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

  /*  */

  /**
   * unicode letters used for parsing html tags, component names and property paths.
   * using https://www.w3.org/TR/html53/semantics-scripting.html#potentialcustomelementname
   * skipping \u10000-\uEFFFF due to it freezing up PhantomJS
   */
  var unicodeRegExp = /a-zA-Z\u00B7\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u037D\u037F-\u1FFF\u200C-\u200D\u203F-\u2040\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-\uFFFD/;

  /**
   * 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 = new RegExp(("[^" + (unicodeRegExp.source) + ".$_\\d]"));
  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;
  var isPhantomJS = UA && /phantomjs/.test(UA);
  var isFF = UA && UA.match(/firefox\/(\d+)/);

  // 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'] && 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) &&