blogging-prompt: preserve language on answers link (#36730)

projects/plugins/jetpack/changelog/preserve-language-on-answers-link

@@ -0,0 +1,4 @@
+Significance: patch
+Type: other
+
+Blogging Prompt: preserve language on answers link

projects/plugins/jetpack/extensions/blocks/blogging-prompt/edit.js

@@ -7,6 +7,7 @@ import { __, _x, sprintf } from '@wordpress/i18n';
 import { addQueryArgs } from '@wordpress/url';
 import clsx from 'clsx';
 import './editor.scss';
+import { languageToLocale } from '../../shared/locale';
 import { usePromptTags } from './use-prompt-tags';
 
 function BloggingPromptEdit( { attributes, noticeOperations, noticeUI, setAttributes } ) {
@@ -101,9 +102,10 @@ function BloggingPromptEdit( { attributes, noticeOperations, noticeUI, setAttrib
 		apiFetch( { path } )
 			.then( prompts => {
 				const promptData = promptId ? prompts : prompts[ 0 ];
+				const locale = languageToLocale( siteLanguage );
 
 				setAttributes( {
-					answersLink: promptData.answered_link,
+					answersLink: promptData.answered_link + `?locale=${ locale }`,
 					answersLinkText: promptData.answered_link_text,
 					gravatars: promptData.answered_users_sample.map( ( { avatar } ) => ( { url: avatar } ) ),
 					promptFetched: true,

projects/plugins/jetpack/extensions/shared/locale.js

@@ -0,0 +1,22 @@
+/**
+ * languageToLocale converts a language tag to an ISO 639 conforming locale string.
+ *
+ * @param {string} language - a language tag to be converted, e.g. "en_US".
+ * @return {string} ISO 639 locale string, e.g. "en".
+ */
+export function languageToLocale( language ) {
+	const withCountryCode = [ 'pt_br', 'pt-br', 'zh_tw', 'zh-tw', 'zh_cn', 'zh-cn' ];
+
+	language = language.toLowerCase();
+	if ( withCountryCode.includes( language ) ) {
+		language = language.replace( '_', '-' );
+	} else {
+		language = language.replace( /([-_].*)$/i, '' );
+	}
+
+	if ( language === '' ) {
+		return 'en';
+	}
+
+	return language;
+}

projects/plugins/jetpack/extensions/shared/test/locale.test.js

@@ -0,0 +1,25 @@
+import { languageToLocale } from '../locale';
+
+describe( 'languageToLocale', () => {
+	test( 'empty string should return en', () => {
+		expect( languageToLocale( '' ) ).toBe( 'en' );
+	} );
+
+	test( 'underscores should be replaced', () => {
+		expect( languageToLocale( 'pt_BR' ) ).toBe( 'pt-br' );
+		expect( languageToLocale( 'zh_CN' ) ).toBe( 'zh-cn' );
+		expect( languageToLocale( 'zh_TW' ) ).toBe( 'zh-tw' );
+	} );
+
+	test( 'country codes should be dropped', () => {
+		expect( languageToLocale( 'en-GB' ) ).toBe( 'en' );
+		expect( languageToLocale( 'en_US' ) ).toBe( 'en' );
+		expect( languageToLocale( 'es-ES' ) ).toBe( 'es' );
+	} );
+
+	test( 'locales should be lowercase', () => {
+		expect( languageToLocale( 'EN' ) ).toBe( 'en' );
+		expect( languageToLocale( 'FR' ) ).toBe( 'fr' );
+		expect( languageToLocale( 'PL' ) ).toBe( 'pl' );
+	} );
+} );