From b3d6988d13e590bf2e55cded27c188013ed69a57 Mon Sep 17 00:00:00 2001
From: Huanyi Xie <74809554+xiehuanyi@users.noreply.github.com>
Date: Thu, 8 Oct 2026 14:25:24 +0300
Subject: [PATCH] fix: derive short years from the full calendar year

---
 src/index.js        |  2 +-
 test/short-years.js | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 test/short-years.js

diff --git a/src/index.js b/src/index.js
index 3ea001b..a213239 100644
--- a/src/index.js
+++ b/src/index.js
@@ -2,7 +2,7 @@ var RGX = /([^{]*?)\w(?=\})/g;
 
 var MAP = {
 	YYYY: 'getFullYear',
-	YY: 'getYear',
+	YY: 'getFullYear',
 	MM: function (d) {
 		return d.getMonth() + 1;
 	},
diff --git a/test/short-years.js b/test/short-years.js
new file mode 100644
index 0000000..5d4f78d
--- /dev/null
+++ b/test/short-years.js
@@ -0,0 +1,12 @@
+const test = require('tape');
+const fn = require('../dist/tinydate');
+
+test('short years before 1900', t => {
+	const stamp = fn('{YY}');
+	for (const year of [1, 50, 99, 1801, 1851, 1899, 1900, 2001]) {
+		const date = new Date(0);
+		date.setFullYear(year);
+		t.is(stamp(date), ('0' + (year % 100)).slice(-2), 'short year for ' + year);
+	}
+	t.end();
+});