Enhance getIn tool

Author: WezomDev

src/get-in.test.ts

@@ -20,6 +20,10 @@ const testCases: {
 		parameters: [{ key: 'value' }, 'ZZZ'],
 		result: undefined
 	},
+	{
+		parameters: [{ key: 'value' }, 'ZZZ', 'fallbackValue'],
+		result: 'fallbackValue'
+	},
 	{
 		parameters: [
 			{
@@ -42,6 +46,16 @@ const testCases: {
 		],
 		result: 'value1'
 	},
+	{
+		parameters: [
+			{
+				key1: ['value0', 'value1', 'value2']
+			},
+			'key1[10]',
+			'fallbackValue'
+		],
+		result: 'fallbackValue'
+	},
 	{
 		parameters: [
 			{

src/get-in.ts

@@ -2,7 +2,6 @@
 // Deps
 // -----------------------------------------------------------------------------
 
-import { IPlainObject } from './types';
 import { toPath } from './to-path';
 import { isPlainObject } from './is-plain-object';
 
@@ -14,28 +13,30 @@ import { isPlainObject } from './is-plain-object';
  * Convert string sample in to the path (array)
  * Inspired by final-form's `getIn` helper
  * {@link https://github.com/final-form/final-form/blob/master/src/structure/getIn.js}
- * @param {IPlainObject|Array} sample
+ * @param {*} sample
  * @param {string} keyPath
+ * @param {*} fallback
  */
-export function getIn<GValue = any>(
-	sample: IPlainObject | GValue[],
-	keyPath: string
-): GValue | undefined {
+export function getIn<GReturnValue = any>(
+	sample: any | any[],
+	keyPath: string,
+	fallback?: GReturnValue
+): GReturnValue {
 	const path = toPath(keyPath);
 	const pathLength = path.length;
 
 	let current: any = sample;
 	for (let i = 0; i < pathLength; i++) {
 		const key: string = path[i];
-		if (
-			(isPlainObject(current) && current.hasOwnProperty(key)) ||
-			(Array.isArray(current) && !isNaN(+key))
-		) {
+		const index = parseInt(key, 10);
+		if (isPlainObject(current) && current.hasOwnProperty(key)) {
 			current = current[key];
+		} else if (Array.isArray(current) && !Number.isNaN(index) && index > -1) {
+			current = current[index];
 		} else {
 			current = undefined;
 			break;
 		}
 	}
-	return current;
+	return current === undefined ? fallback : current;
 }