From 797741c7d06db92eb37431ccd06d998b4ae36cba Mon Sep 17 00:00:00 2001
From: Elian Doran <contact@eliandoran.me>
Date: Tue, 21 Oct 2025 16:54:38 +0300
Subject: [PATCH] fix(client): crash if locale is incorrect

---
 apps/client/src/utils/formatters.spec.ts | 13 +++++++++++++
 apps/client/src/utils/formatters.ts      | 21 +++++++++++++++++----
 2 files changed, 30 insertions(+), 4 deletions(-)
 create mode 100644 apps/client/src/utils/formatters.spec.ts

diff --git a/apps/client/src/utils/formatters.spec.ts b/apps/client/src/utils/formatters.spec.ts
new file mode 100644
index 000000000..4c2f043bc
--- /dev/null
+++ b/apps/client/src/utils/formatters.spec.ts
@@ -0,0 +1,13 @@
+import { describe, expect, it } from "vitest";
+import options from "../services/options";
+import { formatDateTime } from "./formatters";
+
+describe("formatDateTime", () => {
+    it("tolerates incorrect locale", () => {
+        options.set("formattingLocale", "cn_TW");
+
+        expect(formatDateTime(new Date())).toBeTruthy();
+        expect(formatDateTime(new Date(), "full", "none")).toBeTruthy();
+        expect(formatDateTime(new Date(), "none", "full")).toBeTruthy();
+    });
+});
diff --git a/apps/client/src/utils/formatters.ts b/apps/client/src/utils/formatters.ts
index 40f97e673..ab1263a54 100644
--- a/apps/client/src/utils/formatters.ts
+++ b/apps/client/src/utils/formatters.ts
@@ -26,14 +26,27 @@ export function formatDateTime(date: string | Date | number | null | undefined,
 
     if (timeStyle !== "none" && dateStyle !== "none") {
         // Format the date and time
-        const formatter = new Intl.DateTimeFormat(locale, { dateStyle, timeStyle });
-        return formatter.format(parsedDate);
+        try {
+            const formatter = new Intl.DateTimeFormat(locale, { dateStyle, timeStyle });
+            return formatter.format(parsedDate);
+        } catch (e) {
+            const formatter = new Intl.DateTimeFormat(undefined, { dateStyle, timeStyle });
+            return formatter.format(parsedDate);
+        }
     } else if (timeStyle === "none" && dateStyle !== "none") {
         // Format only the date
-        return parsedDate.toLocaleDateString(locale, { dateStyle });
+        try {
+            return parsedDate.toLocaleDateString(locale, { dateStyle });
+        } catch (e) {
+            return parsedDate.toLocaleDateString(undefined, { dateStyle });
+        }
     } else if (dateStyle === "none" && timeStyle !== "none") {
         // Format only the time
-        return parsedDate.toLocaleTimeString(locale, { timeStyle });
+        try {
+            return parsedDate.toLocaleTimeString(locale, { timeStyle });
+        } catch (e) {
+            return parsedDate.toLocaleTimeString(undefined, { timeStyle });
+        }
     }
 
     throw new Error("Incorrect state.");