Add insert option

.verb.md

@@ -104,6 +104,22 @@ set(obj, 'foo.bar.fez', 'zzz', { merge: true });
 //=> { foo: { bar: { baz: 'qux', fez: 'zzz' } } }
 ```
 
+### options.insert
+
+Allows you to insert values to array, instead of overwriting them.
+
+**Type**: `boolean`
+
+**Default**: `undefined`
+
+**Example**
+
+```js
+const obj = { path: { to: { array: ['b', 'c'] } } };
+set(obj, 'path.to.array.0', 'a', { insert: true });
+//=> { path: { to: { array: ['a', 'b', 'c'] } } }
+```
+
 ## Benchmarks
 
 Benchmarks were run on a MacBook Pro 2.5 GHz Intel Core i7, 16 GB 1600 MHz DDR3.

README.md

@@ -1,12 +1,12 @@
-# set-value [![NPM version](https://img.shields.io/npm/v/set-value.svg?style=flat)](https://www.npmjs.com/package/set-value) [![NPM monthly downloads](https://img.shields.io/npm/dm/set-value.svg?style=flat)](https://npmjs.org/package/set-value) [![NPM total downloads](https://img.shields.io/npm/dt/set-value.svg?style=flat)](https://npmjs.org/package/set-value)  [![Tests](https://github.com/jonschlinkert/set-value/actions/workflows/main.yml/badge.svg)](https://github.com/jonschlinkert/set-value/actions/workflows/main.yml)
+# set-value [![NPM version](https://img.shields.io/npm/v/set-value.svg?style=flat)](https://www.npmjs.com/package/set-value) [![NPM monthly downloads](https://img.shields.io/npm/dm/set-value.svg?style=flat)](https://npmjs.org/package/set-value) [![NPM total downloads](https://img.shields.io/npm/dt/set-value.svg?style=flat)](https://npmjs.org/package/set-value) [![Linux Build Status](https://img.shields.io/travis/jonschlinkert/set-value.svg?style=flat&label=Travis)](https://travis-ci.org/jonschlinkert/set-value)
 
 > Set nested properties on an object using dot notation.
 
 Please consider following this project's author, [Jon Schlinkert](https://github.com/jonschlinkert), and consider starring the project to show your :heart: and support.
 
 ## Install
 
-Install with [npm](https://www.npmjs.com/) (requires [Node.js](https://nodejs.org/en/) >=11.0):
+Install with [npm](https://www.npmjs.com/):
 
 ```sh
 $ npm install --save set-value
@@ -116,6 +116,22 @@ set(obj, 'foo.bar.fez', 'zzz', { merge: true });
 //=> { foo: { bar: { baz: 'qux', fez: 'zzz' } } }
 ```
 
+### options.insert
+
+Allows you to insert values to array, instead of overwriting them.
+
+**Type**: `boolean`
+
+**Default**: `undefined`
+
+**Example**
+
+```js
+const obj = { path: { to: { array: ['b', 'c'] } } };
+set(obj, 'path.to.array.0', 'a', { insert: true });
+//=> { path: { to: { array: ['a', 'b', 'c'] } } }
+```
+
 ## Benchmarks
 
 Benchmarks were run on a MacBook Pro 2.5 GHz Intel Core i7, 16 GB 1600 MHz DDR3.
@@ -273,7 +289,7 @@ You might also be interested in these projects:
 
 | **Commits** | **Contributor** |  
 | --- | --- |  
-| 87 | [jonschlinkert](https://github.com/jonschlinkert) |  
+| 90 | [jonschlinkert](https://github.com/jonschlinkert) |  
 | 4  | [doowb](https://github.com/doowb) |  
 | 2  | [mbelsky](https://github.com/mbelsky) |  
 | 1  | [dkebler](https://github.com/dkebler) |  
@@ -299,4 +315,4 @@ Released under the [MIT License](LICENSE).
 
 ***
 
-_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.8.0, on September 12, 2021._
+_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.8.0, on October 06, 2021._

index.js

@@ -40,6 +40,7 @@ const createMemoKey = (input, options) => {
   if (options.separator !== undefined) key += `separator=${options.separator};`;
   if (options.split !== undefined) key += `split=${options.split};`;
   if (options.merge !== undefined) key += `merge=${options.merge};`;
+  if (options.insert !== undefined) key += `insert=${options.insert};`;
   if (options.preservePaths !== undefined) key += `preservePaths=${options.preservePaths};`;
   return key;
 };
@@ -110,17 +111,11 @@ const assignProp = (obj, prop, value, options) => {
   // Delete property when "value" is undefined
   if (value === undefined) {
     deleteProperty(obj, prop);
-
-  } else if (options && options.merge) {
+  } else if (options && options.merge && isPlainObject(obj[prop]) && isPlainObject(value)) {
     const merge = options.merge === 'function' ? options.merge : Object.assign;
-
-    // Only merge plain objects
-    if (merge && isPlainObject(obj[prop]) && isPlainObject(value)) {
-      obj[prop] = merge(obj[prop], value);
-    } else {
-      obj[prop] = value;
-    }
-
+    obj[prop] = merge(obj[prop], value);
+  } else if (options && options.insert && Array.isArray(obj)) {
+    obj.splice(prop, 0, value)
   } else {
     obj[prop] = value;
   }

test/test.js

@@ -238,6 +238,18 @@ describe('set-value', () => {
     });
   });
 
+  describe('options.insert', () => {
+    it('should update an array by inserting the given value', () => {
+      const o = { a: ['a', 'b', 'd'] };
+      set(o, 'a.2', 'c', { insert: true });
+      assert.deepEqual(o.a, ['a', 'b', 'c', 'd']);
+
+      const obj = { path: { to: { array: ['b', 'c'] } } };
+      set(obj, 'path.to.array.0', 'a', { insert: true, merge: true });
+      assert.deepEqual(obj, { path: { to: { array: ['a', 'b', 'c'] } } });
+    });
+  });
+
   describe('options.preservePaths', () => {
     it('should split properties with a forward slash when preservePaths is false', () => {
       const obj = {};