util.js

/**
 * @module zrender/core/util
 */
// 用于处理merge时无法遍历Date等对象的问题
var BUILTIN_OBJECT = {
  '[object Function]': 1,
  '[object RegExp]': 1,
  '[object Date]': 1,
  '[object Error]': 1,
  '[object CanvasGradient]': 1,
  '[object CanvasPattern]': 1,
  // For node-canvas
  '[object Image]': 1,
  '[object Canvas]': 1
};
var TYPED_ARRAY = {
  '[object Int8Array]': 1,
  '[object Uint8Array]': 1,
  '[object Uint8ClampedArray]': 1,
  '[object Int16Array]': 1,
  '[object Uint16Array]': 1,
  '[object Int32Array]': 1,
  '[object Uint32Array]': 1,
  '[object Float32Array]': 1,
  '[object Float64Array]': 1
};
var objToString = Object.prototype.toString;
var arrayProto = Array.prototype;
var nativeForEach = arrayProto.forEach;
var nativeFilter = arrayProto.filter;
var nativeSlice = arrayProto.slice;
var nativeMap = arrayProto.map;
var nativeReduce = arrayProto.reduce; // Avoid assign to an exported variable, for transforming to cjs.

var methods = {};

function $override(name, fn) {
  // Clear ctx instance for different environment
  if (name === 'createCanvas') {
    _ctx = null;
  }

  methods[name] = fn;
}
/**
 * Those data types can be cloned:
 *     Plain object, Array, TypedArray, number, string, null, undefined.
 * Those data types will be assgined using the orginal data:
 *     BUILTIN_OBJECT
 * Instance of user defined class will be cloned to a plain object, without
 * properties in prototype.
 * Other data types is not supported (not sure what will happen).
 *
 * Caution: do not support clone Date, for performance consideration.
 * (There might be a large number of date in `series.data`).
 * So date should not be modified in and out of echarts.
 *
 * @param {*} source
 * @return {*} new
 */


function clone(source) {
  if (source == null || typeof source !== 'object') {
    return source;
  }

  var result = source;
  var typeStr = objToString.call(source);

  if (typeStr === '[object Array]') {
    if (!isPrimitive(source)) {
      result = [];

      for (var i = 0, len = source.length; i < len; i++) {
        result[i] = clone(source[i]);
      }
    }
  } else if (TYPED_ARRAY[typeStr]) {
    if (!isPrimitive(source)) {
      var Ctor = source.constructor;

      if (source.constructor.from) {
        result = Ctor.from(source);
      } else {
        result = new Ctor(source.length);

        for (var i = 0, len = source.length; i < len; i++) {
          result[i] = clone(source[i]);
        }
      }
    }
  } else if (!BUILTIN_OBJECT[typeStr] && !isPrimitive(source) && !isDom(source)) {
    result = {};

    for (var key in source) {
      if (source.hasOwnProperty(key)) {
        result[key] = clone(source[key]);
      }
    }
  }

  return result;
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} target
 * @param {*} source
 * @param {boolean} [overwrite=false]
 */


function merge(target, source, overwrite) {
  // We should escapse that source is string
  // and enter for ... in ...
  if (!isObject(source) || !isObject(target)) {
    return overwrite ? clone(source) : target;
  }

  for (var key in source) {
    if (source.hasOwnProperty(key)) {
      var targetProp = target[key];
      var sourceProp = source[key];

      if (isObject(sourceProp) && isObject(targetProp) && !isArray(sourceProp) && !isArray(targetProp) && !isDom(sourceProp) && !isDom(targetProp) && !isBuiltInObject(sourceProp) && !isBuiltInObject(targetProp) && !isPrimitive(sourceProp) && !isPrimitive(targetProp)) {
        // 如果需要递归覆盖，就递归调用merge
        merge(targetProp, sourceProp, overwrite);
      } else if (overwrite || !(key in target)) {
        // 否则只处理overwrite为true，或者在目标对象中没有此属性的情况
        // NOTE，在 target[key] 不存在的时候也是直接覆盖
        target[key] = clone(source[key], true);
      }
    }
  }

  return target;
}
/**
 * @param {Array} targetAndSources The first item is target, and the rests are source.
 * @param {boolean} [overwrite=false]
 * @return {*} target
 */


function mergeAll(targetAndSources, overwrite) {
  var result = targetAndSources[0];

  for (var i = 1, len = targetAndSources.length; i < len; i++) {
    result = merge(result, targetAndSources[i], overwrite);
  }

  return result;
}
/**
 * @param {*} target
 * @param {*} source
 * @memberOf module:zrender/core/util
 */


function extend(target, source) {
  for (var key in source) {
    if (source.hasOwnProperty(key)) {
      target[key] = source[key];
    }
  }

  return target;
}
/**
 * @param {*} target
 * @param {*} source
 * @param {boolean} [overlay=false]
 * @memberOf module:zrender/core/util
 */


function defaults(target, source, overlay) {
  for (var key in source) {
    if (source.hasOwnProperty(key) && (overlay ? source[key] != null : target[key] == null)) {
      target[key] = source[key];
    }
  }

  return target;
}

var createCanvas = function () {
  return methods.createCanvas();
};

methods.createCanvas = function () {
  return document.createElement('canvas');
}; // FIXME


var _ctx;

function getContext() {
  if (!_ctx) {
    // Use util.createCanvas instead of createCanvas
    // because createCanvas may be overwritten in different environment
    _ctx = createCanvas().getContext('2d');
  }

  return _ctx;
}
/**
 * 查询数组中元素的index
 * @memberOf module:zrender/core/util
 */


function indexOf(array, value) {
  if (array) {
    if (array.indexOf) {
      return array.indexOf(value);
    }

    for (var i = 0, len = array.length; i < len; i++) {
      if (array[i] === value) {
        return i;
      }
    }
  }

  return -1;
}
/**
 * 构造类继承关系
 *
 * @memberOf module:zrender/core/util
 * @param {Function} clazz 源类
 * @param {Function} baseClazz 基类
 */


function inherits(clazz, baseClazz) {
  var clazzPrototype = clazz.prototype;

  function F() {}

  F.prototype = baseClazz.prototype;
  clazz.prototype = new F();

  for (var prop in clazzPrototype) {
    clazz.prototype[prop] = clazzPrototype[prop];
  }

  clazz.prototype.constructor = clazz;
  clazz.superClass = baseClazz;
}
/**
 * @memberOf module:zrender/core/util
 * @param {Object|Function} target
 * @param {Object|Function} sorce
 * @param {boolean} overlay
 */


function mixin(target, source, overlay) {
  target = 'prototype' in target ? target.prototype : target;
  source = 'prototype' in source ? source.prototype : source;
  defaults(target, source, overlay);
}
/**
 * Consider typed array.
 * @param {Array|TypedArray} data
 */


function isArrayLike(data) {
  if (!data) {
    return;
  }

  if (typeof data === 'string') {
    return false;
  }

  return typeof data.length === 'number';
}
/**
 * 数组或对象遍历
 * @memberOf module:zrender/core/util
 * @param {Object|Array} obj
 * @param {Function} cb
 * @param {*} [context]
 */


function each(obj, cb, context) {
  if (!(obj && cb)) {
    return;
  }

  if (obj.forEach && obj.forEach === nativeForEach) {
    obj.forEach(cb, context);
  } else if (obj.length === +obj.length) {
    for (var i = 0, len = obj.length; i < len; i++) {
      cb.call(context, obj[i], i, obj);
    }
  } else {
    for (var key in obj) {
      if (obj.hasOwnProperty(key)) {
        cb.call(context, obj[key], key, obj);
      }
    }
  }
}
/**
 * 数组映射
 * @memberOf module:zrender/core/util
 * @param {Array} obj
 * @param {Function} cb
 * @param {*} [context]
 * @return {Array}
 */


function map(obj, cb, context) {
  if (!(obj && cb)) {
    return;
  }

  if (obj.map && obj.map === nativeMap) {
    return obj.map(cb, context);
  } else {
    var result = [];

    for (var i = 0, len = obj.length; i < len; i++) {
      result.push(cb.call(context, obj[i], i, obj));
    }

    return result;
  }
}
/**
 * @memberOf module:zrender/core/util
 * @param {Array} obj
 * @param {Function} cb
 * @param {Object} [memo]
 * @param {*} [context]
 * @return {Array}
 */


function reduce(obj, cb, memo, context) {
  if (!(obj && cb)) {
    return;
  }

  if (obj.reduce && obj.reduce === nativeReduce) {
    return obj.reduce(cb, memo, context);
  } else {
    for (var i = 0, len = obj.length; i < len; i++) {
      memo = cb.call(context, memo, obj[i], i, obj);
    }

    return memo;
  }
}
/**
 * 数组过滤
 * @memberOf module:zrender/core/util
 * @param {Array} obj
 * @param {Function} cb
 * @param {*} [context]
 * @return {Array}
 */


function filter(obj, cb, context) {
  if (!(obj && cb)) {
    return;
  }

  if (obj.filter && obj.filter === nativeFilter) {
    return obj.filter(cb, context);
  } else {
    var result = [];

    for (var i = 0, len = obj.length; i < len; i++) {
      if (cb.call(context, obj[i], i, obj)) {
        result.push(obj[i]);
      }
    }

    return result;
  }
}
/**
 * 数组项查找
 * @memberOf module:zrender/core/util
 * @param {Array} obj
 * @param {Function} cb
 * @param {*} [context]
 * @return {*}
 */


function find(obj, cb, context) {
  if (!(obj && cb)) {
    return;
  }

  for (var i = 0, len = obj.length; i < len; i++) {
    if (cb.call(context, obj[i], i, obj)) {
      return obj[i];
    }
  }
}
/**
 * @memberOf module:zrender/core/util
 * @param {Function} func
 * @param {*} context
 * @return {Function}
 */


function bind(func, context) {
  var args = nativeSlice.call(arguments, 2);
  return function () {
    return func.apply(context, args.concat(nativeSlice.call(arguments)));
  };
}
/**
 * @memberOf module:zrender/core/util
 * @param {Function} func
 * @return {Function}
 */


function curry(func) {
  var args = nativeSlice.call(arguments, 1);
  return function () {
    return func.apply(this, args.concat(nativeSlice.call(arguments)));
  };
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isArray(value) {
  return objToString.call(value) === '[object Array]';
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isFunction(value) {
  return typeof value === 'function';
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isString(value) {
  return objToString.call(value) === '[object String]';
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isObject(value) {
  // Avoid a V8 JIT bug in Chrome 19-20.
  // See https://code.google.com/p/v8/issues/detail?id=2291 for more details.
  var type = typeof value;
  return type === 'function' || !!value && type === 'object';
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isBuiltInObject(value) {
  return !!BUILTIN_OBJECT[objToString.call(value)];
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isTypedArray(value) {
  return !!TYPED_ARRAY[objToString.call(value)];
}
/**
 * @memberOf module:zrender/core/util
 * @param {*} value
 * @return {boolean}
 */


function isDom(value) {
  return typeof value === 'object' && typeof value.nodeType === 'number' && typeof value.ownerDocument === 'object';
}
/**
 * Whether is exactly NaN. Notice isNaN('a') returns true.
 * @param {*} value
 * @return {boolean}
 */


function eqNaN(value) {
  return value !== value;
}
/**
 * If value1 is not null, then return value1, otherwise judget rest of values.
 * Low performance.
 * @memberOf module:zrender/core/util
 * @return {*} Final value
 */


function retrieve(values) {
  for (var i = 0, len = arguments.length; i < len; i++) {
    if (arguments[i] != null) {
      return arguments[i];
    }
  }
}

function retrieve2(value0, value1) {
  return value0 != null ? value0 : value1;
}

function retrieve3(value0, value1, value2) {
  return value0 != null ? value0 : value1 != null ? value1 : value2;
}
/**
 * @memberOf module:zrender/core/util
 * @param {Array} arr
 * @param {number} startIndex
 * @param {number} endIndex
 * @return {Array}
 */


function slice() {
  return Function.call.apply(nativeSlice, arguments);
}
/**
 * Normalize css liked array configuration
 * e.g.
 *  3 => [3, 3, 3, 3]
 *  [4, 2] => [4, 2, 4, 2]
 *  [4, 3, 2] => [4, 3, 2, 3]
 * @param {number|Array.<number>} val
 * @return {Array.<number>}
 */


function normalizeCssArray(val) {
  if (typeof val === 'number') {
    return [val, val, val, val];
  }

  var len = val.length;

  if (len === 2) {
    // vertical | horizontal
    return [val[0], val[1], val[0], val[1]];
  } else if (len === 3) {
    // top | horizontal | bottom
    return [val[0], val[1], val[2], val[1]];
  }

  return val;
}
/**
 * @memberOf module:zrender/core/util
 * @param {boolean} condition
 * @param {string} message
 */


function assert(condition, message) {
  if (!condition) {
    throw new Error(message);
  }
}
/**
 * @memberOf module:zrender/core/util
 * @param {string} str string to be trimed
 * @return {string} trimed string
 */


function trim(str) {
  if (str == null) {
    return null;
  } else if (typeof str.trim === 'function') {
    return str.trim();
  } else {
    return str.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
  }
}

var primitiveKey = '__ec_primitive__';
/**
 * Set an object as primitive to be ignored traversing children in clone or merge
 */

function setAsPrimitive(obj) {
  obj[primitiveKey] = true;
}

function isPrimitive(obj) {
  return obj[primitiveKey];
}
/**
 * @constructor
 * @param {Object} obj Only apply `ownProperty`.
 */


function HashMap(obj) {
  var isArr = isArray(obj); // Key should not be set on this, otherwise
  // methods get/set/... may be overrided.

  this.data = {};
  var thisMap = this;
  obj instanceof HashMap ? obj.each(visit) : obj && each(obj, visit);

  function visit(value, key) {
    isArr ? thisMap.set(value, key) : thisMap.set(key, value);
  }
}

HashMap.prototype = {
  constructor: HashMap,
  // Do not provide `has` method to avoid defining what is `has`.
  // (We usually treat `null` and `undefined` as the same, different
  // from ES6 Map).
  get: function (key) {
    return this.data.hasOwnProperty(key) ? this.data[key] : null;
  },
  set: function (key, value) {
    // Comparing with invocation chaining, `return value` is more commonly
    // used in this case: `var someVal = map.set('a', genVal());`
    return this.data[key] = value;
  },
  // Although util.each can be performed on this hashMap directly, user
  // should not use the exposed keys, who are prefixed.
  each: function (cb, context) {
    context !== void 0 && (cb = bind(cb, context));

    for (var key in this.data) {
      this.data.hasOwnProperty(key) && cb(this.data[key], key);
    }
  },
  // Do not use this method if performance sensitive.
  removeKey: function (key) {
    delete this.data[key];
  }
};

function createHashMap(obj) {
  return new HashMap(obj);
}

function concatArray(a, b) {
  var newArray = new a.constructor(a.length + b.length);

  for (var i = 0; i < a.length; i++) {
    newArray[i] = a[i];
  }

  var offset = a.length;

  for (i = 0; i < b.length; i++) {
    newArray[i + offset] = b[i];
  }

  return newArray;
}

function noop() {}

exports.$override = $override;
exports.clone = clone;
exports.merge = merge;
exports.mergeAll = mergeAll;
exports.extend = extend;
exports.defaults = defaults;
exports.createCanvas = createCanvas;
exports.getContext = getContext;
exports.indexOf = indexOf;
exports.inherits = inherits;
exports.mixin = mixin;
exports.isArrayLike = isArrayLike;
exports.each = each;
exports.map = map;
exports.reduce = reduce;
exports.filter = filter;
exports.find = find;
exports.bind = bind;
exports.curry = curry;
exports.isArray = isArray;
exports.isFunction = isFunction;
exports.isString = isString;
exports.isObject = isObject;
exports.isBuiltInObject = isBuiltInObject;
exports.isTypedArray = isTypedArray;
exports.isDom = isDom;
exports.eqNaN = eqNaN;
exports.retrieve = retrieve;
exports.retrieve2 = retrieve2;
exports.retrieve3 = retrieve3;
exports.slice = slice;
exports.normalizeCssArray = normalizeCssArray;
exports.assert = assert;
exports.trim = trim;
exports.setAsPrimitive = setAsPrimitive;
exports.isPrimitive = isPrimitive;
exports.createHashMap = createHashMap;
exports.concatArray = concatArray;
exports.noop = noop;