@mpxjs/utils/src/base.js

A toolkit for mpx framework

const noop = () => { }

function isString (str) {
  return typeof str === 'string'
}

function isBoolean (bool) {
  return typeof bool === 'boolean'
}

function isNumber (num) {
  return typeof num === 'number'
}

function isArray (arr) {
  return Array.isArray(arr)
}

function isFunction (fn) {
  return typeof fn === 'function'
}

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

function isObject (obj) {
  return obj !== null && typeof obj === 'object'
}

function isPromise (val) {
  return (
    (isObject(val) || isFunction(val)) &&
    isFunction(val.then) &&
    isFunction(val.catch)
  )
}

function isEmptyObject (obj) {
  if (!obj) {
    return true
  }
  /* eslint-disable no-unreachable-loop */
  for (const key in obj) {
    return false
  }
  return true
}

function forEach (obj, fn) {
  if (obj === null || typeof obj === 'undefined') {
    return
  }

  if (typeof obj !== 'object') {
    obj = [obj]
  }

  if (isArray(obj)) {
    for (let i = 0, l = obj.length; i < l; i++) {
      fn(obj[i], i, obj)
    }
  } else {
    for (const key in obj) {
      if (Object.prototype.hasOwnProperty.call(obj, key)) {
        fn(obj[key], key, obj)
      }
    }
  }
}

function isNumberStr (str) {
  return /^\d+$/.test(str)
}

function isValidIdentifierStr (str) {
  return /^[A-Za-z_$][A-Za-z0-9_$]*$/.test(str)
}

const hasProto = '__proto__' in {}

function cached (fn) {
  const cache = Object.create(null)
  return function cachedFn (str) {
    const hit = cache[str]
    return hit || (cache[str] = fn(str))
  }
}

const dash2hump = cached((value) => {
  return value.replace(/-([a-z])/g, function (_, p1) {
    return p1.toUpperCase()
  })
})

const hump2dash = cached((value) => {
  return value.replace(/[A-Z]/g, function (match) {
    return '-' + match.toLowerCase()
  })
})

function def (obj, key, val, enumerable) {
  Object.defineProperty(obj, key, {
    value: val,
    enumerable: !!enumerable,
    writable: true,
    configurable: true
  })
}

// type在支付宝环境下不一定准确，判断是普通对象优先使用isPlainObject（新版支付宝不复现，issue #644 修改isPlainObject实现与type等价）
function type (n) {
  return Object.prototype.toString.call(n).slice(8, -1)
}

function aliasReplace (options = {}, alias, target) {
  if (options[alias]) {
    if (Array.isArray(options[alias])) {
      options[target] = options[alias].concat(options[target] || [])
    } else if (isObject(options[alias])) {
      options[target] = Object.assign({}, options[alias], options[target])
    } else {
      options[target] = options[alias]
    }
    delete options[alias]
  }
  return options
}

// 比较一个值是否发生了变化（考虑NaN）。
function hasChanged (value, oldValue) {
  return !Object.is(value, oldValue)
}

export {
  hasProto,
  noop,
  type,
  isString,
  isBoolean,
  isNumber,
  isArray,
  isFunction,
  isObject,
  isPromise,
  isEmptyObject,
  isDef,
  isNumberStr,
  isValidIdentifierStr,
  aliasReplace,
  dash2hump,
  hump2dash,
  def,
  hasChanged,
  forEach,
  cached
}