From c6e200dc0feceee39da6a10c654c6fc0ffa0c94d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?V=C3=A1clav=20Kubern=C3=A1t?= <sir.venceslas@gmail.com>
Date: Wed, 30 Oct 2024 18:18:34 +0100
Subject: [PATCH 1/2] chainpack: Don't serialize 0 dateime offset

---
 package.json     | 2 +-
 src/chainpack.ts | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/package.json b/package.json
index 3619f37..cd91bb1 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "libshv-js",
-  "version": "3.4.1",
+  "version": "3.4.2",
   "description": "Typescript implementation of libshv",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
diff --git a/src/chainpack.ts b/src/chainpack.ts
index 40d3ed6..98ae9bc 100644
--- a/src/chainpack.ts
+++ b/src/chainpack.ts
@@ -559,14 +559,14 @@ class ChainPackWriter {
         }
 
         let bi = BigInt(msecs);
-        if (dt.utc_offset !== undefined) {
+        if (dt.utc_offset !== undefined && dt.utc_offset !== 0) {
             bi <<= 7n;
             bi |= BigInt((dt.utc_offset / 15) & 0x7F);
         }
 
         bi <<= 2n;
 
-        if (dt.utc_offset !== undefined) {
+        if (dt.utc_offset !== undefined && dt.utc_offset !== 0) {
             bi |= 1n;
         }
 

From 1c6ce663e4b130ff55b1b6e4ca88acbb3c4626cc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?V=C3=A1clav=20Kubern=C3=A1t?= <sir.venceslas@gmail.com>
Date: Wed, 30 Oct 2024 18:19:51 +0100
Subject: [PATCH 2/2] Don't deserialize 0 offset

---
 src/chainpack.ts | 2 +-
 src/cpon.ts      | 2 +-
 test.ts          | 1 +
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/chainpack.ts b/src/chainpack.ts
index 98ae9bc..1c43669 100644
--- a/src/chainpack.ts
+++ b/src/chainpack.ts
@@ -178,7 +178,7 @@ class ChainPackReader {
 
                 msec += SHV_EPOCH_MSEC;
                 msec -= offset * 60_000;
-                return withOffset(new Date(msec), offset);
+                return withOffset(new Date(msec), offset ?? undefined);
             }
 
             case PackingSchema.Map: {
diff --git a/src/cpon.ts b/src/cpon.ts
index 41a37da..ac50553 100644
--- a/src/cpon.ts
+++ b/src/cpon.ts
@@ -315,7 +315,7 @@ class CponReader {
         // let epoch_sec = CponReader.timegm(year, month, mday, hour, min, sec);
         let epochMsec = Date.UTC(year, month - 1, day, hour, min, sec, msec);
         epochMsec -= utcOffset * 60_000;
-        return withOffset(new Date(epochMsec), utcOffset);
+        return withOffset(new Date(epochMsec), utcOffset ?? undefined);
     }
 
     readCString() {
diff --git a/test.ts b/test.ts
index a21c08f..5a297cf 100644
--- a/test.ts
+++ b/test.ts
@@ -64,6 +64,7 @@ for (const lst of [
     ['<4:"svete">i{2:<4:"svete">[0,1]}', null],
     ['d"2019-05-03T11:30:00-0700"', 'd"2019-05-03T11:30:00-07"'],
     ['d"2018-02-02T00:00:00Z"', null],
+    ['d"2024-10-30T16:30:57.890Z"', null],
     ['d"2027-05-03T11:30:12.345+01"', null],
 ]) {
     const cpon1 = lst[0];