From ec2c16fefa8b98efaa1ccf84f18eea0a12c1c9ef Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Mon, 30 Jan 2023 22:20:29 +0200
Subject: fix `assert()` crash (#1941)

---
 src/string_immutable.zig   | 2 +-
 test/bun.js/buffer.test.js | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/string_immutable.zig b/src/string_immutable.zig
index a437baa69..e949892e1 100644
--- a/src/string_immutable.zig
+++ b/src/string_immutable.zig
@@ -1419,7 +1419,7 @@ pub fn convertUTF8BytesIntoUTF16(sequence: *const [4]u8) UTF16Replacement {
     switch (len) {
         2 => {
             if (Environment.allow_assert)
-                assert(sequence[0] >= 0xC2);
+                assert(sequence[0] >= 0xC0);
             if (Environment.allow_assert)
                 assert(sequence[0] <= 0xDF);
             if (sequence[1] < 0x80 or sequence[1] > 0xBF) {
diff --git a/test/bun.js/buffer.test.js b/test/bun.js/buffer.test.js
index 1971fed8c..d1ed5a496 100644
--- a/test/bun.js/buffer.test.js
+++ b/test/bun.js/buffer.test.js
@@ -2813,3 +2813,11 @@ test("Buffer.byteLength", () => {
     );
   }
 });
+
+it("should not crash on invalid UTF-8 byte sequence", () => {
+  const buf = Buffer.from([0xC0, 0xFD]).toString();
+  expect(buf.length).toBe(2);
+  const str = buf.toString();
+  expect(str.length).toBe(2);
+  expect(str).toBe("\uFFFD\uFFFD");
+});
-- 
cgit v1.2.3