1 files changed, 86 insertions, 0 deletions
diff --git a/toolkit/components/translations/tests/browser/browser_translations_actor_detected_langs.js b/toolkit/components/translations/tests/browser/browser_translations_actor_detected_langs.js
new file mode 100644
index 0000000000..65479a968e
--- /dev/null
+++ b/toolkit/components/translations/tests/browser/browser_translations_actor_detected_langs.js
@@ -0,0 +1,86 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+add_task(async function test_detected_language() {
+  const { cleanup, tab } = await loadTestPage({
+    // This page will get its language changed by the test.
+    page: ENGLISH_PAGE_URL,
+    autoDownloadFromRemoteSettings: true,
+    languagePairs: [
+      // Spanish
+      { fromLang: "es", toLang: "en" },
+      { fromLang: "en", toLang: "es" },
+
+      // Norwegian Bokmål
+      { fromLang: "nb", toLang: "en" },
+      { fromLang: "en", toLang: "nb" },
+    ],
+  });
+
+  async function getDetectedLanguagesFor(docLangTag) {
+    await ContentTask.spawn(
+      tab.linkedBrowser,
+      { docLangTag },
+      function changeLanguage({ docLangTag }) {
+        content.document.body.parentNode.setAttribute("lang", docLangTag);
+      }
+    );
+    // Clear out the cached values.
+    getTranslationsParent().languageState.detectedLanguages = null;
+    return getTranslationsParent().getDetectedLanguages(docLangTag);
+  }
+
+  Assert.deepEqual(
+    await getDetectedLanguagesFor("es"),
+    {
+      docLangTag: "es",
+      userLangTag: "en",
+      isDocLangTagSupported: true,
+    },
+    "Spanish is detected as a supported language."
+  );
+
+  Assert.deepEqual(
+    await getDetectedLanguagesFor("chr"),
+    {
+      docLangTag: "chr",
+      userLangTag: "en",
+      isDocLangTagSupported: false,
+    },
+    "Cherokee is detected, but is not a supported language."
+  );
+
+  Assert.deepEqual(
+    await getDetectedLanguagesFor("no"),
+    {
+      docLangTag: "nb",
+      userLangTag: "en",
+      isDocLangTagSupported: true,
+    },
+    "The Norwegian macro language is detected, but it defaults to Norwegian Bokmål."
+  );
+
+  Assert.deepEqual(
+    await getDetectedLanguagesFor("spa"),
+    {
+      docLangTag: "es",
+      userLangTag: "en",
+      isDocLangTagSupported: true,
+    },
+    'The three letter "spa" locale is canonicalized to "es".'
+  );
+
+  Assert.deepEqual(
+    await getDetectedLanguagesFor("gibberish"),
+    {
+      docLangTag: "en",
+      userLangTag: null,
+      isDocLangTagSupported: true,
+    },
+    "A gibberish locale is discarded, and the language is detected."
+  );
+
+  return cleanup();
+});