From 4baa58838fd46860902463a754998ccf48f5072a Mon Sep 17 00:00:00 2001
From: Neele Barthel <neele.barthel@shopify.com>
Date: Wed, 19 Feb 2020 13:27:32 -0500
Subject: [PATCH] Memoize NumberFormat as well

---
 packages/react-i18n/src/i18n.ts               |  2 +-
 .../react-i18n/src/temporary-format-date.ts   | 57 -------------------
 .../react-i18n/src/utilities/translate.tsx    | 21 ++++---
 3 files changed, 14 insertions(+), 66 deletions(-)
 delete mode 100644 packages/react-i18n/src/temporary-format-date.ts

diff --git a/packages/react-i18n/src/i18n.ts b/packages/react-i18n/src/i18n.ts
index b93bd359e1..b4940ace80 100644
--- a/packages/react-i18n/src/i18n.ts
+++ b/packages/react-i18n/src/i18n.ts
@@ -1,4 +1,5 @@
 import {
+  formatDate,
   isLessThanOneHourAgo,
   isLessThanOneMinuteAgo,
   isLessThanOneWeekAgo,
@@ -41,7 +42,6 @@ import {
   memoizedNumberFormatter,
   memoizedPluralRules,
 } from './utilities';
-import {formatDate} from './temporary-format-date';
 
 export interface NumberFormatOptions extends Intl.NumberFormatOptions {
   as?: 'number' | 'currency' | 'percent';
diff --git a/packages/react-i18n/src/temporary-format-date.ts b/packages/react-i18n/src/temporary-format-date.ts
deleted file mode 100644
index 5a365a5c64..0000000000
--- a/packages/react-i18n/src/temporary-format-date.ts
+++ /dev/null
@@ -1,57 +0,0 @@
-const intl = new Map();
-const memoizedGetDateTimeFormat = function(locale, options) {
-  const key = dateTimeFormatCacheKey(locale, options);
-  if (intl.has(key)) {
-    return intl.get(key);
-  }
-  const i = new Intl.DateTimeFormat(locale, options);
-  intl.set(key, i);
-  return i;
-};
-
-const browserFeatureDetectionDate = Intl.DateTimeFormat('en', {
-  hour: 'numeric',
-});
-
-interface FormatDateOptions extends Intl.DateTimeFormatOptions {
-  hourCycle?: string;
-}
-
-const resolvedOptions: FormatDateOptions | undefined =
-  typeof browserFeatureDetectionDate.resolvedOptions === 'undefined'
-    ? undefined
-    : browserFeatureDetectionDate.resolvedOptions();
-
-export function formatDate(
-  date: Date,
-  locales: string | string[],
-  options: FormatDateOptions = {},
-) {
-  const hourCycleRequired =
-    resolvedOptions != null &&
-    options.hour12 != null &&
-    resolvedOptions.hourCycle != null;
-
-  if (hourCycleRequired) {
-    options.hour12 = undefined;
-    options.hourCycle = 'h23';
-  }
-
-  // Etc/GMT+12 is not supported in most browsers and there is no equivalent fallback
-  if (options.timeZone != null && options.timeZone === 'Etc/GMT+12') {
-    const adjustedDate = new Date(date.valueOf() - 12 * 60 * 60 * 1000);
-    return memoizedGetDateTimeFormat(locales, {
-      ...options,
-      timeZone: 'UTC',
-    }).format(adjustedDate);
-  }
-
-  return memoizedGetDateTimeFormat(locales, options).format(date);
-}
-
-function dateTimeFormatCacheKey(
-  locales: string | string[],
-  options?: Intl.DateTimeFormatOptions,
-) {
-  return `${locales}-${JSON.stringify(options)}`;
-}
diff --git a/packages/react-i18n/src/utilities/translate.tsx b/packages/react-i18n/src/utilities/translate.tsx
index 464f866a12..66d3d23ee9 100644
--- a/packages/react-i18n/src/utilities/translate.tsx
+++ b/packages/react-i18n/src/utilities/translate.tsx
@@ -17,6 +17,17 @@ const MISSING_TRANSLATION = Symbol('Missing translation');
 const PLURALIZATION_KEY_NAME = 'count';
 const SEPARATOR = '.';
 
+const numberFormats = new Map();
+export const memoizedNumberFormatter = function(locale, options = {}) {
+  const key = numberFormatCacheKey(locale, options);
+  if (numberFormats.has(key)) {
+    return numberFormats.get(key);
+  }
+  const i = new Intl.NumberFormat(locale, options);
+  numberFormats.set(key, i);
+  return i;
+};
+
 export const PSEUDOTRANSLATE_OPTIONS: PseudotranslateOptions = {
   startDelimiter: '{',
   endDelimiter: '}',
@@ -30,19 +41,13 @@ export interface TranslateOptions<Replacements = {}> {
   pseudotranslate?: boolean | string;
 }
 
-function numberFormatter(
+function numberFormatCacheKey(
   locale: string,
   options: Intl.NumberFormatOptions = {},
 ) {
-  return new Intl.NumberFormat(locale, options);
+  return `${locale}${JSON.stringify(options)}`;
 }
 
-export const memoizedNumberFormatter = memoizeFn(
-  numberFormatter,
-  (locale: string, options: Intl.NumberFormatOptions = {}) =>
-    `${locale}${JSON.stringify(options)}`,
-);
-
 function pluralRules(locale: string, options: Intl.PluralRulesOptions = {}) {
   return new Intl.PluralRules(locale, options);
 }