From 5f41e6076daab49f6fefe76979837d3acd13a03a Mon Sep 17 00:00:00 2001
From: James Lu <Ellipse120@users.noreply.github.com>
Date: Wed, 12 Apr 2023 10:40:59 +0800
Subject: [PATCH] Refactor nested object merge using Immutable-js

The commit refactors the code to use the `mergeDeepWith` function of `Im
mutable-js` to keep the nested object original structure.
---
 note.md | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)

diff --git a/note.md b/note.md
index 352519c..58a30b7 100644
--- a/note.md
+++ b/note.md
@@ -4319,3 +4319,78 @@ const refreshPage = async () => {
 
 ---
 
+## 155. Using function `mergeDeepWith` of `Immutable-js` to keep nested object original structure.
+
+```js
+const { mergeDeepWith } = require(’immutable@4.3.0‘)
+
+const original = { 
+	x: {
+	  	y: 123,
+	  	z: {
+	  		a: {
+	  			b: null
+	  		}
+	  	}
+	},
+	user: {
+		menu: {
+			codes: []
+		},
+		info: {
+			name: null,
+			age: null
+		}
+	}
+}
+
+const responseData = {
+	x: {
+	  	y: 123,
+	  	z: null
+	},
+	user: {
+		menu: null,
+		info: {
+			name: ’James‘,
+			age: 37
+		}
+	}
+}
+
+const result = mergeDeepWith(
+  (oldVal, newVal) => {
+  	if ([null, ’‘, undefined].includes(newVal)) {
+  		return oldVal
+  	}
+    
+    return newVal
+  },
+  original,
+  responseData
+)
+
+console.error(result)
+/**
+* x: {
+  	y: 123,
+  	z: {
+  		a: {
+  			b: null
+  		}
+  	}
+},
+user: {
+	menu: {
+		codes: []
+	},
+	info: {
+		name: ’James‘,
+		age: 37
+	}
+}
+*/
+```
+
+—
+