Merge pull request #20 from dictor93/feature/extend-pick-functionality

Feature/extend pick functionality

CHANGELOG

@@ -1,3 +1,6 @@
+# 1.8.1
+- feat: extended pick functionality by using multiple path parameters and nested pick
+
 # 1.8.0
 - feat: max
 - feat: min

package.json

@@ -1,6 +1,6 @@
 {
  "name": "@bitfinexcom/lib-js-util-base",
- "version": "1.8.0",
+ "version": "1.8.1",
  "description": "general utils",
  "main": "index.js",
  "scripts": {

src/get.js

@@ -1,14 +1,6 @@
 'use strict'
 
-/**
- *
- * @param {string} path
- * @returns {Array<string>}
- */
-const pathToArray = (path) => {
- if (Array.isArray(path)) return path
- return path.split(/\[|\]\.|\]\[|\.|\]/gm).filter((key) => key !== '')
-}
+const pathToArray = require('./util/pathToArray')
 
 /**
  *

src/pick.js

@@ -1,14 +1,65 @@
 'use strict'
 
-const pick = (obj, keys) => {
+const get = require('./get')
+const pathToArray = require('./util/pathToArray')
+
+/**
+ *
+ * @param {any} nested
+ * @param {Array<string>} path
+ * @param {any} value
+ * @returns
+ */
+const _setObjByPath = (nested, path, value) => {
+ if (path.length === 1) {
+ return Object.assign(nested, { [path[0]]: value })
+ }
+
+ const currentProp = path.shift()
+ if (nested[currentProp] === undefined) {
+ nested[currentProp] = {}
+ }
+
+ return _setObjByPath(nested[currentProp], path, value)
+}
+
+/**
+ *
+ * @param {object} src
+ * @param {object} dest
+ * @param {string | Array<string>} path
+ * @returns
+ */
+const _pickByPath = (src, dest, path) => {
+ const pathArr = pathToArray(path)
+
+ const value = get(src, [...pathArr])
+ if (value !== undefined) {
+ _setObjByPath(dest, pathArr, value)
+ }
+ return dest
+}
+
+/**
+ *
+ * @param {any} obj
+ * @param {...(string | Array<string | Array<strig>>)} pathes
+ * @returns
+ */
+const pick = (obj, ...pathes) => {
  if (obj === null) {
  return {}
  }
 
  const newObj = {}
- for (const key in obj) {
- if (keys.includes(key)) {
- newObj[key] = obj[key]
+ for (const path of pathes) {
+ if (typeof path === 'string') {
+ _pickByPath(obj, newObj, path)
+ }
+ if (Array.isArray(path)) {
+ for (const chunk of path) {
+ _pickByPath(obj, newObj, chunk)
+ }
  }
  }
 

src/util/pathToArray.js

@@ -0,0 +1,13 @@
+'use strict'
+
+/**
+ *
+ * @param {string} path
+ * @returns {Array<string>}
+ */
+const pathToArray = (path) => {
+ if (Array.isArray(path)) return path
+ return path.split(/\[|\]\.|\]\[|\.|\]/gm).filter((key) => key !== '')
+}
+
+module.exports = pathToArray

test/pick.js

@@ -29,4 +29,49 @@ describe('pick', () => {
  it('should handle keys that are not strings', () => {
  assert.deepStrictEqual(pick({ 1: 'one', 2: 'two' }, ['1', '2']), { 1: 'one', 2: 'two' })
  })
+
+ it('should pick properties by few path parameters', () => {
+ const src = { a: 1, b: 2, c: 3, d: 4 }
+ const expected = { a: 1, b: 2, d: 4 }
+ assert.deepStrictEqual(pick(src, ['a', 'b'], 'd'), expected)
+ })
+
+ it('should pick nested properties by string or array path', () => {
+ const src = {
+ a: 1,
+ b: {
+ c: { d: 5, g: 2, h: 7 },
+ f: 6
+ },
+ e: 4
+ }
+ const expected = {
+ a: 1,
+ b: {
+ c: { d: 5, h: 7 }
+ }
+ }
+
+ assert.deepStrictEqual(
+ pick(
+ src,
+ ['a', 'b.c.d', 'b.c.h'],
+ 'd'
+ ),
+ expected
+ )
+ assert.deepStrictEqual(
+ pick(
+ src,
+ ['a', ['b', 'c', 'd'], ['b', 'c', 'h']],
+ 'd'
+ ),
+ expected
+ )
+ })
+
+ it('should return empty object if path is not specified', () => {
+ const src = { a: 1, b: { c: { d: 5, g: 2, h: 7 }, f: 6 }, e: 4 }
+ assert.deepStrictEqual(pick(src, ''), {})
+ })
 })