From 6279ce8f227e6338e3d6485c6511d81a4feb2fe4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Acid=20Chicken=20=28=E7=A1=AB=E9=85=B8=E9=B6=8F=29?=
 <root@acid-chicken.com>
Date: Tue, 19 Feb 2019 04:04:05 +0900
Subject: [PATCH] Add fallback for locales (#4109)

* Update index.js

* Update index.js
---
 locales/index.js | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/locales/index.js b/locales/index.js
index 96a1af38b..9642b400a 100644
--- a/locales/index.js
+++ b/locales/index.js
@@ -8,6 +8,19 @@ const yaml = require('js-yaml');
 const langs = ['de-DE', 'en-US', 'fr-FR', 'ja-JP', 'ja-KS', 'pl-PL', 'es-ES', 'nl-NL', 'zh-CN', 'ko-KR'];
 
 const loadLocale = lang => yaml.safeLoad(fs.readFileSync(`${__dirname}/${lang}.yml`, 'utf-8'));
-const locales = langs.map(lang => ({ [lang]: loadLocale(lang) }));
+const locales = langs
+	.map(lang => [lang, loadLocale(lang)])
+	.map(([lang, locale], _, locales) => {
+		switch (lang) {
+			case 'ja-JP': return [lang, locale];
+			case 'en-US': return [lang, { ...locales['ja-JP'], ...locale }];
+			default: return [lang, {
+				(lang.startsWith('ja-') ? {} : ...locales['en-US']),
+				...locales['ja-JP'],
+				...locale
+		}];
+		}
+	})
+	.map(([lang, locale]) => ({ [lang]: loadLocale(lang) }));
 
 module.exports = locales.reduce((a, b) => ({ ...a, ...b }));