From 780e826ff863502f21ae95979c6a100ba90fc797 Mon Sep 17 00:00:00 2001
From: AbhilashG12 <abhilashggg15@gmail.com>
Date: Fri, 25 Sep 2026 10:58:20 +0530
Subject: [PATCH] fix(adapter-pg): prepend + to expanded years in timestamps to
 prevent Invalid Date

Signed-off-by: AbhilashG12 <abhilashggg15@gmail.com>
---
 .../src/__tests__/conversion.test.ts          | 23 ++++++++++++++++++-
 packages/adapter-pg/src/conversion.ts         | 10 ++++----
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/packages/adapter-pg/src/__tests__/conversion.test.ts b/packages/adapter-pg/src/__tests__/conversion.test.ts
index e438c2e405df..3bfc3949be48 100644
--- a/packages/adapter-pg/src/__tests__/conversion.test.ts
+++ b/packages/adapter-pg/src/__tests__/conversion.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 
-import { mapArg } from '../conversion'
+import { mapArg, normalize_timestamp, normalize_timestamptz } from '../conversion'
 
 describe('mapArg', () => {
   it('converts a date with a 4-digit year (value >= 1000-01-01) to the correct date', () => {
@@ -39,3 +39,24 @@ describe('mapArg', () => {
     expect(result).toBe('0099-12-31 23:59:59.999')
   })
 })
+
+describe('normalize_timestamp', () => {
+  it('leaves standard 4-digit years unaffected', () => {
+    expect(normalize_timestamp('2026-09-02 05:00:00')).toBe('2026-09-02T05:00:00+00:00')
+  })
+
+  it('prepends + to expanded years (>9999) to satisfy ISO 8601', () => {
+    expect(normalize_timestamp('202609-02-05 05:00:00')).toBe('+202609-02-05T05:00:00+00:00')
+  })
+})
+
+describe('normalize_timestamptz', () => {
+  it('leaves standard 4-digit years unaffected', () => {
+    // Note: Postgres timestamptz wire format includes the timezone offset
+    expect(normalize_timestamptz('2026-09-02 05:00:00+00')).toBe('2026-09-02T05:00:00+00:00')
+  })
+
+  it('prepends + to expanded years (>9999) to satisfy ISO 8601', () => {
+    expect(normalize_timestamptz('202609-02-05 05:00:00+00')).toBe('+202609-02-05T05:00:00+00:00')
+  })
+})
diff --git a/packages/adapter-pg/src/conversion.ts b/packages/adapter-pg/src/conversion.ts
index 2bf2183a9578..80a749c534c1 100644
--- a/packages/adapter-pg/src/conversion.ts
+++ b/packages/adapter-pg/src/conversion.ts
@@ -305,12 +305,14 @@ function normalize_date(date: string): string {
  * ex: 1996-12-19T16:39:57-08:00
  */
 
-function normalize_timestamp(time: string): string {
-  return `${time.replace(' ', 'T')}+00:00`
+export function normalize_timestamp(time: string): string {
+  const iso = `${time.replace(' ', 'T')}+00:00`
+  return /^\d{5,}/.test(iso) ? '+' + iso : iso
 }
 
-function normalize_timestamptz(time: string): string {
-  return time.replace(' ', 'T').replace(/[+-]\d{2}(:\d{2})?$/, '+00:00')
+export function normalize_timestamptz(time: string): string {
+  const iso = time.replace(' ', 'T').replace(/[+-]\d{2}(:\d{2})?$/, '+00:00')
+  return /^\d{5,}/.test(iso) ? '+' + iso : iso
 }
 
 /*