@revoloo/cypress6/packages/driver/src/cy/chai/inspect.js

Cypress.io end to end testing tool

// Changes made: added 'formatValueHook' to process value before being formatted.
// For example the hook can be used to turn `window` objects into the string '[window]'
// to avoid deep recursion.

// This is (almost) directly from chai/lib/util (which is based on nodejs utils)
// https://github.com/joyent/node/blob/f8c335d0caf47f16d31413f89aa28eda3878e3aa/lib/util.js

// let getName = require('get-func-name')
// let getProperties = require('./getProperties')
let getEnumerableProperties = require('chai/lib/chai/utils/getEnumerableProperties')
// let config = require('../config')

module.exports = {

  create (chai) {
    const { getName, getProperties } = chai.util
    const { config } = chai

    /**
     * ### .inspect(obj, [showHidden], [depth], [colors])
     *
     * Echoes the value of a value. Tries to print the value out
     * in the best way possible given the different types.
     *
     * @param {Object} obj The object to print out.
     * @param {Boolean} showHidden Flag that shows hidden (not enumerable)
     *    properties of objects. Default is false.
     * @param {Number} depth Depth in which to descend in object. Default is 2.
     * @param {Boolean} colors Flag to turn on ANSI escape codes to color the
     *    output. Default is false (no coloring).
     * @namespace Utils
     * @name inspect
     */
    function inspect (obj, showHidden, depth, colors) {
      let ctx = {
        showHidden,
        seen: [],
        stylize (str) {
          return str
        },
      }

      return formatValue(ctx, obj, (typeof depth === 'undefined' ? 2 : depth))
    }

    // Returns true if object is a DOM element.
    let isDOMElement = function (object) {
      if (typeof HTMLElement === 'object') {
        return object instanceof HTMLElement
      }

      return object &&
      typeof object === 'object' &&
      'nodeType' in object &&
      object.nodeType === 1 &&
      typeof object.nodeName === 'string'
    }

    let formatValueHook

    const setFormatValueHook = (fn) => formatValueHook = fn

    function formatValue (ctx, value, recurseTimes) {
      // Provide a hook for user-specified inspect functions.
      // Check that value is an object with an inspect function on it

      const hookRet = formatValueHook && formatValueHook(ctx, value)

      if (hookRet) {
        return hookRet
      }

      if (value && typeof value.inspect === 'function' &&
      // Filter out the util module, it's inspect function is special
      value.inspect !== exports.inspect &&
      // Also filter out any prototype objects using the circular check.
      !(value.constructor && value.constructor.prototype === value)) {
        let ret = value.inspect(recurseTimes, ctx)

        if (typeof ret !== 'string') {
          ret = formatValue(ctx, ret, recurseTimes)
        }

        return ret
      }

      // Primitive types cannot have properties
      let primitive = formatPrimitive(ctx, value)

      if (primitive) {
        return primitive
      }

      // If this is a DOM element, try to get the outer HTML.
      if (isDOMElement(value)) {
        if ('outerHTML' in value) {
          return value.outerHTML
          // This value does not have an outerHTML attribute,
          //   it could still be an XML element
        }

        // Attempt to serialize it
        try {
          if (document.xmlVersion) {
            let xmlSerializer = new XMLSerializer()

            return xmlSerializer.serializeToString(value)
          }

          // Firefox 11- do not support outerHTML
          //   It does, however, support innerHTML
          //   Use the following to render the element
          let ns = 'http://www.w3.org/1999/xhtml'
          let container = document.createElementNS(ns, '_')

          container.appendChild(value.cloneNode(false))
          let html = container.innerHTML
          .replace('><', `>${value.innerHTML}<`)

          container.innerHTML = ''

          return html
        } catch (err) {
          // This could be a non-native DOM implementation,
          //   continue with the normal flow:
          //   printing the element as if it is an object.
        }
      }

      // Look up the keys of the object.
      let visibleKeys = getEnumerableProperties(value)
      let keys = ctx.showHidden ? getProperties(value) : visibleKeys

      let name; let nameSuffix

      // Some type of object without properties can be shortcut.
      // In IE, errors have a single `stack` property, or if they are vanilla `Error`,
      // a `stack` plus `description` property; ignore those for consistency.
      if (keys.length === 0 || (isError(value) && (
        (keys.length === 1 && keys[0] === 'stack') ||
      (keys.length === 2 && keys[0] === 'description' && keys[1] === 'stack')
      ))) {
        if (typeof value === 'function') {
          name = getName(value)
          nameSuffix = name ? `: ${name}` : ''

          return ctx.stylize(`[Function${nameSuffix}]`, 'special')
        }

        if (isRegExp(value)) {
          return ctx.stylize(RegExp.prototype.toString.call(value), 'regexp')
        }

        if (isDate(value)) {
          return ctx.stylize(Date.prototype.toUTCString.call(value), 'date')
        }

        if (isError(value)) {
          return formatError(value)
        }
      }

      let base = ''
      let array = false
      let typedArray = false
      let braces = ['{', '}']

      if (isTypedArray(value)) {
        typedArray = true
        braces = ['[', ']']
      }

      // Make Array say that they are Array
      if (isArray(value)) {
        array = true
        braces = ['[', ']']
      }

      // Make functions say that they are functions
      if (typeof value === 'function') {
        name = getName(value)
        nameSuffix = name ? `: ${name}` : ''
        base = ` [Function${nameSuffix}]`
      }

      // Make RegExps say that they are RegExps
      if (isRegExp(value)) {
        base = ` ${RegExp.prototype.toString.call(value)}`
      }

      // Make dates with properties first say the date
      if (isDate(value)) {
        base = ` ${Date.prototype.toUTCString.call(value)}`
      }

      // Make error with message first say the error
      if (isError(value)) {
        return formatError(value)
      }

      // eslint-disable-next-line eqeqeq
      if (keys.length === 0 && (!array || value.length == 0)) {
        return braces[0] + base + braces[1]
      }

      if (recurseTimes < 0) {
        if (isRegExp(value)) {
          return ctx.stylize(RegExp.prototype.toString.call(value), 'regexp')
        }

        return ctx.stylize('[Object]', 'special')
      }

      ctx.seen.push(value)

      let output

      if (array) {
        output = formatArray(ctx, value, recurseTimes, visibleKeys, keys)
      } else if (typedArray) {
        return formatTypedArray(value)
      } else {
        output = keys.map(function (key) {
          return formatProperty(ctx, value, recurseTimes, visibleKeys, key, array)
        })
      }

      ctx.seen.pop()

      return reduceToSingleString(output, base, braces)
    }

    function formatPrimitive (ctx, value) {
      switch (typeof value) {
        case 'undefined':
          return ctx.stylize('undefined', 'undefined')

        case 'string': {
          const simple = `'${JSON.stringify(value).replace(/^"|"$/g, '')
          .replace(/'/g, '\\\'')
          .replace(/\\"/g, '"')}'`

          return ctx.stylize(simple, 'string')
        }

        case 'number':
          if (value === 0 && (1 / value) === -Infinity) {
            return ctx.stylize('-0', 'number')
          }

          return ctx.stylize(`${value}`, 'number')

        case 'boolean':
          return ctx.stylize(`${value}`, 'boolean')

        case 'symbol':
          return ctx.stylize(value.toString(), 'symbol')
        default:
          null
      }
      // For some reason typeof null is "object", so special case here.
      if (value === null) {
        return ctx.stylize('null', 'null')
      }
    }

    function formatError (value) {
      return `[${Error.prototype.toString.call(value)}]`
    }

    function formatArray (ctx, value, recurseTimes, visibleKeys, keys) {
      let output = []

      for (let i = 0, l = value.length; i < l; ++i) {
        if (Object.prototype.hasOwnProperty.call(value, String(i))) {
          output.push(formatProperty(ctx, value, recurseTimes, visibleKeys,
            String(i), true))
        } else {
          output.push('')
        }
      }

      keys.forEach(function (key) {
        if (!key.match(/^\d+$/)) {
          output.push(formatProperty(ctx, value, recurseTimes, visibleKeys,
            key, true))
        }
      })

      return output
    }

    function formatTypedArray (value) {
      let str = '[ '

      for (let i = 0; i < value.length; ++i) {
        if (str.length >= config.truncateThreshold - 7) {
          str += '...'
          break
        }

        str += `${value[i]}, `
      }
      str += ' ]'

      // Removing trailing `, ` if the array was not truncated
      if (str.indexOf(',  ]') !== -1) {
        str = str.replace(',  ]', ' ]')
      }

      return str
    }

    function formatProperty (ctx, value, recurseTimes, visibleKeys, key, array) {
      let name
      let propDescriptor = Object.getOwnPropertyDescriptor(value, key)
      let str

      if (propDescriptor) {
        if (propDescriptor.get) {
          if (propDescriptor.set) {
            str = ctx.stylize('[Getter/Setter]', 'special')
          } else {
            str = ctx.stylize('[Getter]', 'special')
          }
        } else {
          if (propDescriptor.set) {
            str = ctx.stylize('[Setter]', 'special')
          }
        }
      }

      if (visibleKeys.indexOf(key) < 0) {
        name = `[${key}]`
      }

      if (!str) {
        if (ctx.seen.indexOf(value[key]) < 0) {
          if (recurseTimes === null) {
            str = formatValue(ctx, value[key], null)
          } else {
            str = formatValue(ctx, value[key], recurseTimes - 1)
          }

          if (str.indexOf('\n') > -1) {
            if (array) {
              str = str.split('\n').map(function (line) {
                return `  ${line}`
              }).join('\n').substr(2)
            } else {
              str = `\n${str.split('\n').map(function (line) {
                return `   ${line}`
              }).join('\n')}`
            }
          }
        } else {
          str = ctx.stylize('[Circular]', 'special')
        }
      }

      if (typeof name === 'undefined') {
        if (array && key.match(/^\d+$/)) {
          return str
        }

        name = JSON.stringify(`${key}`)
        if (name.match(/^"([a-zA-Z_][a-zA-Z_0-9]*)"$/)) {
          name = name.substr(1, name.length - 2)
          name = ctx.stylize(name, 'name')
        } else {
          name = name.replace(/'/g, '\\\'')
          .replace(/\\"/g, '"')
          .replace(/(^"|"$)/g, '\'')

          name = ctx.stylize(name, 'string')
        }
      }

      return `${name}: ${str}`
    }

    function reduceToSingleString (output, base, braces) {
      let length = output.reduce(function (prev, cur) {
        return prev + cur.length + 1
      }, 0)

      if (length > 60) {
        return `${braces[0] +
           (base === '' ? '' : `${base}\n `)
        } ${
          output.join(',\n  ')
        } ${
          braces[1]}`
      }

      return `${braces[0] + base} ${output.join(', ')} ${braces[1]}`
    }

    function isTypedArray (ar) {
      // Unfortunately there's no way to check if an object is a TypedArray
      // We have to check if it's one of these types
      return (typeof ar === 'object' && /\w+Array]$/.test(objectToString(ar)))
    }

    function isArray (ar) {
      return Array.isArray(ar) ||
         (typeof ar === 'object' && objectToString(ar) === '[object Array]')
    }

    function isRegExp (re) {
      return typeof re === 'object' && objectToString(re) === '[object RegExp]'
    }

    function isDate (d) {
      return typeof d === 'object' && objectToString(d) === '[object Date]'
    }

    function isError (e) {
      return typeof e === 'object' && objectToString(e) === '[object Error]'
    }

    function objectToString (o) {
      return Object.prototype.toString.call(o)
    }

    return {
      inspect,
      setFormatValueHook,
    }
  },
}