From 8f5fd2f06c92fe080817e249a3c313212b753c46 Mon Sep 17 00:00:00 2001
From: Kohei Ueno <kohei.ueno119@gmail.com>
Date: Fri, 29 Jul 2022 14:47:56 +0900
Subject: [PATCH] src: fix to use replacement character

PR-URL: https://github.com/nodejs/node/pull/43999
Fixes: https://github.com/nodejs/node/issues/43962
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Mohammed Keyvanzadeh <mohammadkeyvanzade94@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>
Reviewed-By: Feng Yu <F3n67u@outlook.com>
---
 src/node_i18n.cc                                         | 6 +++++-
 test/parallel/test-whatwg-encoding-custom-textdecoder.js | 7 +++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/node_i18n.cc b/src/node_i18n.cc
index c537a247f55ff0..d96efaa9df7b2f 100644
--- a/src/node_i18n.cc
+++ b/src/node_i18n.cc
@@ -425,7 +425,11 @@ void ConverterObject::Create(const FunctionCallbackInfo<Value>& args) {
                         nullptr, nullptr, nullptr, &status);
   }
 
-  new ConverterObject(env, obj, conv, flags);
+  auto converter = new ConverterObject(env, obj, conv, flags);
+  size_t sublen = ucnv_getMinCharSize(conv);
+  std::string sub(sublen, '?');
+  converter->set_subst_chars(sub.c_str());
+
   args.GetReturnValue().Set(obj);
 }
 
diff --git a/test/parallel/test-whatwg-encoding-custom-textdecoder.js b/test/parallel/test-whatwg-encoding-custom-textdecoder.js
index 1fa65164c70678..fe08edc597d3f4 100644
--- a/test/parallel/test-whatwg-encoding-custom-textdecoder.js
+++ b/test/parallel/test-whatwg-encoding-custom-textdecoder.js
@@ -199,3 +199,10 @@ if (common.hasIntl) {
   const str = decoder.decode(chunk);
   assert.strictEqual(str, 'foo\ufffd');
 }
+
+if (common.hasIntl) {
+  const decoder = new TextDecoder('Shift_JIS');
+  const chunk = new Uint8Array([-1]);
+  const str = decoder.decode(chunk);
+  assert.strictEqual(str, '\ufffd');
+}