From 5a0fbe1badf615364bbcffe937fa5d74c593d7b3 Mon Sep 17 00:00:00 2001
From: Johan Girod <johangirod@gmail.com>
Date: Mon, 14 May 2018 10:47:20 +0200
Subject: [PATCH] :bug: fix invalid language tag when passing locale argument
 to iframe

---
 source/i18n.js  |  5 ++---
 source/utils.js | 15 ++++++++++++++-
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/source/i18n.js b/source/i18n.js
index 8a3b6b3ad..d9f9907d5 100644
--- a/source/i18n.js
+++ b/source/i18n.js
@@ -1,14 +1,13 @@
-import { I18nextProvider } from 'react-i18next'
 import i18next from 'i18next'
 import queryString from 'query-string'
 
-import { getIframeOption } from './utils'
+import { getIframeOption, parseDataAttributes } from './utils'
 import enTranslations from './locales/en.yaml'
 
 let lang =
 	getIframeOption('lang') ||
 	queryString.parse(location.search)['lang'] ||
-	sessionStorage['lang'] ||
+	parseDataAttributes(sessionStorage['lang']) ||
 	'fr'
 
 sessionStorage['lang'] = lang
diff --git a/source/utils.js b/source/utils.js
index 8781c7c88..cdb1cb8c3 100644
--- a/source/utils.js
+++ b/source/utils.js
@@ -1,8 +1,21 @@
 export let capitalise0 = name => name[0].toUpperCase() + name.slice(1)
 
 export let getUrl = () => window.location.href.toString()
+
+export let parseDataAttributes = value =>
+	value === 'undefined'
+		? undefined
+		: value === null
+			? null
+			: !isNaN(value)
+				? +value
+				: /* value is a normal string */
+				  value
+
 export let getIframeOption = optionName => {
 	let url = getUrl(),
 		hasOption = url.includes(optionName + '=')
-	return hasOption && url.split(optionName + '=')[1].split('&')[0]
+	return parseDataAttributes(
+		hasOption && url.split(optionName + '=')[1].split('&')[0]
+	)
 }