From fa65611b9d4adc029baef2e27b09490deb45d97a Mon Sep 17 00:00:00 2001
From: Mike Bostock <mbostock@gmail.com>
Date: Tue, 30 Mar 2021 12:57:04 -0700
Subject: [PATCH] use Intl.DateTimeFormat

---
 src/format.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/format.js b/src/format.js
index a60b89d4a2..de6bdcfd13 100644
--- a/src/format.js
+++ b/src/format.js
@@ -1,17 +1,17 @@
 export function formatMonth(locale, month = "short") {
-  const format = {timeZone: "UTC", month};
+  const format = new Intl.DateTimeFormat(locale, {timeZone: "UTC", month});
   return i => {
     if (i != null && !isNaN(i = new Date(Date.UTC(2000, +i)))) {
-      return i.toLocaleString(locale, format);
+      return format.format(i);
     }
   };
 }
 
 export function formatWeekday(locale, weekday = "short") {
-  const format = {timeZone: "UTC", weekday};
+  const format = new Intl.DateTimeFormat(locale, {timeZone: "UTC", weekday});
   return i => {
     if (i != null && !isNaN(i = new Date(Date.UTC(2001, 0, +i)))) {
-      return i.toLocaleString(locale, format);
+      return format.format(i);
     }
   };
 }