Functions to copy properties between projects including read-only, non-enumerable and get/set

.npmignore

source.js

readme.md

@actualwave/assign-own-props

index.js

'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

const { hasOwn } = require('@actualwave/has-own');

/*
  Will throw error on trying to assign non-configurable property twice
*/
const assignOwnPropsUnsafe = (target, ...sources) => {
  sources.forEach((source) => Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)));

  return target;
};

const filterSources = (list) => list.filter((source) => source !== undefined && source !== null);
const filterDescriptor = (target, name) => !hasOwn(target, name);
const listPropertyNames = (descriptors) => Object.keys(descriptors);

/*
  Allows to create special logic for assigining property descriptors by configuring
  touchPropFn - alter every property descriptor
  touchSourcesFn - access list of source objects before assigning properties
  getDescriptors - function to retrieve property descriptors
  filter - decides if property descriptor can be applied to a target
*/
const createAssignOwnProps = (
  touchPropFn = (descriptor) => descriptor,
  touchSourcesFn = filterSources,
  getDescriptors = Object.getOwnPropertyDescriptors,
  listNames = listPropertyNames,
  filterProp = filterDescriptor,
) => (target, ...sources) => {
  touchSourcesFn(sources).forEach((source) => {
    const descriptors = getDescriptors(source);
    listNames(descriptors).forEach((name) => {
      if (filterProp(target, name)) {
        Object.defineProperty(target, name, touchPropFn(descriptors[name], name, target));
      }
    });
  });

  return target;
};

const assignOwnProps = createAssignOwnProps();

/*
  As you  can see -- instead of re-assigning next descriptor for same property, I reversed array,
  so last descriptor being used.
*/
const assignOwnPropsOverwrite = createAssignOwnProps(undefined, (list) => filterSources([...list]).reverse());

/*
  Assign properties and alter each with properties from "sharedPart"
  Make every property enumerable:
  assignOwnPropsAlter(targetObj, { enumerable: true }, sourceObj1, sourceObj2);
  Actually overwrite properties:
  assignOwnPropsAlter(targetObj, { configurable: true }, sourceObj1, sourceObj2);
*/
const assignOwnPropsAlter = (() => {
  let overwritePart;

  const assignAndAlter = createAssignOwnProps((descriptor) => ({ ...descriptor, ...overwritePart }));

  return (target, sharedPart, ...sources) => {
    overwritePart = sharedPart;

    return assignAndAlter(target, ...sources);
  };
})();

exports.assignOwnPropsUnsafe = assignOwnPropsUnsafe;
exports.createAssignOwnProps = createAssignOwnProps;
exports.assignOwnProps = assignOwnProps;
exports.assignOwnPropsOverwrite = assignOwnPropsOverwrite;
exports.assignOwnPropsAlter = assignOwnPropsAlter;

exports.default = assignOwnProps;

package.json

{
  "name": "@actualwave/assign-own-props",
  "description": "Functions to copy properties between projects including read-only, non-enumerable and get/set",
  "version": "0.0.1",
  "main": "index.js",
  "keywords": [
    "object",
    "property",
    "assign",
    "Object.assign",
    "hasOwn",
    "getOwnPropertyDescriptors",
    "defineProperty",
    "defineProperties",
    "Object.keys"
  ],
  "author": {
    "name": "Oleg Galaburda",
    "email": "[email protected]",
    "url": "http://actualwave.com/"
  },
  "bugs": {
    "url": "https://gist.github.com/burdiuz/f530f5d53f5a74e5155cd43cf060e808",
    "email": "[email protected]"
  },
  "homepage": "https://gist.github.com/burdiuz/f530f5d53f5a74e5155cd43cf060e808",
  "dependencies": {
    "@actualwave/has-own": "0.0.1"
  },
  "license": "MIT"
}

source.js

import hasOwn from '@actualwave/has-own';

/*
  Will throw error on trying to assign non-configurable property twice
*/
export const assignOwnPropsUnsafe = (target, ...sources) => {
  sources.forEach((source) => Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)));

  return target;
};

const filterSources = (list) => list.filter((source) => source !== undefined && source !== null);
const filterDescriptor = (target, name) => !hasOwn(target, name);
const listPropertyNames = (descriptors) => Object.keys(descriptors);

/*
  Allows to create special logic for assigining property descriptors by configuring
  touchPropFn - alter every property descriptor
  touchSourcesFn - access list of source objects before assigning properties
  getDescriptors - function to retrieve property descriptors
  filter - decides if property descriptor can be applied to a target
*/
export const createAssignOwnProps = (
  touchPropFn = (descriptor) => descriptor,
  touchSourcesFn = filterSources,
  getDescriptors = Object.getOwnPropertyDescriptors,
  listNames = listPropertyNames,
  filterProp = filterDescriptor,
) => (target, ...sources) => {
  touchSourcesFn(sources).forEach((source) => {
    const descriptors = getDescriptors(source);
    listNames(descriptors).forEach((name) => {
      if (filterProp(target, name)) {
        Object.defineProperty(target, name, touchPropFn(descriptors[name], name, target));
      }
    });
  });

  return target;
};

export const assignOwnProps = createAssignOwnProps();

/*
  As you  can see -- instead of re-assigning next descriptor for same property, I reversed array,
  so last descriptor being used.
*/
export const assignOwnPropsOverwrite = createAssignOwnProps(undefined, (list) => filterSources([...list]).reverse());

/*
  Assign properties and alter each with properties from "sharedPart"
  Make every property enumerable:
  assignOwnPropsAlter(targetObj, { enumerable: true }, sourceObj1, sourceObj2);
  Actually overwrite properties:
  assignOwnPropsAlter(targetObj, { configurable: true }, sourceObj1, sourceObj2);
*/
export const assignOwnPropsAlter = (() => {
  let overwritePart;

  const assignAndAlter = createAssignOwnProps((descriptor) => ({ ...descriptor, ...overwritePart }));

  return (target, sharedPart, ...sources) => {
    overwritePart = sharedPart;

    return assignAndAlter(target, ...sources);
  };
})();