From ae660d19216d0aff585e3caa27a7b585d3f0fe0a Mon Sep 17 00:00:00 2001
From: Harvey <harvey0379@163.com>
Date: Sat, 11 Mar 2023 18:53:51 +0800
Subject: [PATCH] Huauauaa/cheat-sheet#73 defineProperty

---
 test/prototype.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 test/prototype.test.js

diff --git a/test/prototype.test.js b/test/prototype.test.js
new file mode 100644
index 0000000..e883613
--- /dev/null
+++ b/test/prototype.test.js
@@ -0,0 +1,24 @@
+import * as assert from 'assert';
+
+describe('prototype', function () {
+  const foo = { id: 1, name: 'foo' };
+  foo.__proto__.bar = 'bar';
+  it('for in', function () {
+    for (const key in foo) {
+      console.log(key);
+    }
+    assert.strictEqual(foo.bar, 'bar');
+  });
+  it('keys', function () {
+    Object.keys(foo).forEach((key) => console.log(key));
+  });
+
+  it('writable', function () {
+    Object.defineProperty(foo, 'id', { writable: false });
+    // TypeError: Cannot assign to read only property 'id' of object '#<Object>'
+    // foo.id = 2;
+    foo.name = 'foo1';
+    assert.strictEqual(foo.id, 1);
+    assert.strictEqual(foo.name, 'foo1');
+  });
+});