inspect-property/lib/inspect-property.js

Inspects a Property and returns useful informations about it (e.g. nested properties, function inspection, property descriptor, value, type, constructor)

'use strict';

const _inspectFunction = require('inspect-function');
const forEachProperty = require('for-each-property');
const forEachPropertyDeep = require('for-each-property-deep');

function inspectProperty(o, propertyName, { delimiter = '.', inspectFunction = true, inspectProperties = true, enumerability, inherited } = {}) {
  const property = o && propertyName ? o[propertyName] : o;
  const propertyInspection = {
    value: property,
    type: typeof(property),
    constructor: {
      name: property && property.constructor && property.constructor.name,
      ref: property && property.constructor
    }
  };

  if (o && propertyName) {
    propertyInspection.propertyDescriptor = Object.getOwnPropertyDescriptor(o, propertyName);
  }

  if (propertyInspection.type === 'function' && inspectFunction) {
    propertyInspection.functionInspection = _inspectFunction(property);
  }

  if (propertyInspection.type === 'function' || propertyInspection.type === 'object') {
    propertyInspection.properties = forEachPropertyDeep(property, (value, key, path, parent, state) => {
      state[path.join(delimiter)] = value;
    }, { enumerability, inherited });

    forEachProperty(propertyInspection.properties, (value, key) => {
      propertyInspection.properties[key] = value === undefined || value === null || !inspectProperties ? value : inspectProperty(value, null, { inspectFunction, inspectProperties: false });
    });
  }

  return propertyInspection;
}

module.exports = inspectProperty;