Check source language to determine if page can be manually translated.

Bug: 907134, 902803
Change-Id: Ifb63346572e90a191918bcfe30d24f4362c10b45
Reviewed-on: https://chromium-review.googlesource.com/c/1344256Reviewed-by: anthonyvd <anthonyvd@chromium.org>
Commit-Queue: anthonyvd <anthonyvd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609789}

components/translate/core/browser/translate_manager.cc

@@ -321,23 +321,33 @@ std::string TranslateManager::GetManualTargetLanguage(
 }
 
 bool TranslateManager::CanManuallyTranslate() {
+  if (!base::FeatureList::IsEnabled(translate::kTranslateUI) ||
+      net::NetworkChangeNotifier::IsOffline() ||
+      (!ignore_missing_key_for_testing_ &&
+       !::google_apis::HasAPIKeyConfigured()))
+    return false;
+
+  // MHTML pages currently cannot be translated (crbug.com/217945).
+  if (translate_driver_->GetContentsMimeType() == "multipart/related" ||
+      !translate_client_->IsTranslatableURL(
+          translate_driver_->GetVisibleURL()) ||
+      !language_state_.page_needs_translation())
+    return false;
+
+  const std::string source_language = language_state_.original_language();
+  if (source_language.empty() ||
+      source_language == translate::kUnknownLanguageCode)
+    return false;
+
   std::unique_ptr<TranslatePrefs> translate_prefs(
       translate_client_->GetTranslatePrefs());
-  const std::string source_code = TranslateDownloadManager::GetLanguageCode(
-      language_state_.original_language());
   const std::string target_lang = GetManualTargetLanguage(
-      source_code, language_state_, translate_prefs.get(), language_model_);
+      TranslateDownloadManager::GetLanguageCode(source_language),
+      language_state_, translate_prefs.get(), language_model_);
+  if (target_lang.empty())
+    return false;
 
-  return language_state_.page_needs_translation() &&
-         base::FeatureList::IsEnabled(translate::kTranslateUI) &&
-         !net::NetworkChangeNotifier::IsOffline() &&
-         (ignore_missing_key_for_testing_ ||
-          ::google_apis::HasAPIKeyConfigured()) &&
-         // MHTML pages currently cannot be translated (crbug.com/217945).
-         translate_driver_->GetContentsMimeType() != "multipart/related" &&
-         translate_client_->IsTranslatableURL(
-             translate_driver_->GetVisibleURL()) &&
-         !target_lang.empty();
+  return true;
 }
 
 void TranslateManager::InitiateManualTranslation() {

components/translate/core/browser/translate_manager_unittest.cc

@@ -26,6 +26,7 @@
 #include "components/translate/core/browser/translate_download_manager.h"
 #include "components/translate/core/browser/translate_pref_names.h"
 #include "components/translate/core/browser/translate_prefs.h"
+#include "components/translate/core/common/translate_constants.h"
 #include "components/variations/variations_associated_data.h"
 #include "net/base/network_change_notifier.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ -920,6 +921,37 @@ TEST_F(TranslateManagerTest, CanManuallyTranslate_TranslatableURL) {
   EXPECT_TRUE(translate_manager_->CanManuallyTranslate());
 }
 
+TEST_F(TranslateManagerTest, CanManuallyTranslate_EmptySourceLanguage) {
+  TranslateManager::SetIgnoreMissingKeyForTesting(true);
+  translate_manager_.reset(new translate::TranslateManager(
+      &mock_translate_client_, &mock_translate_ranker_, &mock_language_model_));
+
+  prefs_.SetBoolean(prefs::kOfferTranslateEnabled, true);
+  network_notifier_.SimulateOnline();
+  ON_CALL(mock_translate_client_, IsTranslatableURL(GURL::EmptyGURL()))
+      .WillByDefault(Return(true));
+
+  translate_manager_->GetLanguageState().LanguageDetermined("", true);
+
+  EXPECT_FALSE(translate_manager_->CanManuallyTranslate());
+}
+
+TEST_F(TranslateManagerTest, CanManuallyTranslate_UndefinedSourceLanguage) {
+  TranslateManager::SetIgnoreMissingKeyForTesting(true);
+  translate_manager_.reset(new translate::TranslateManager(
+      &mock_translate_client_, &mock_translate_ranker_, &mock_language_model_));
+
+  prefs_.SetBoolean(prefs::kOfferTranslateEnabled, true);
+  network_notifier_.SimulateOnline();
+  ON_CALL(mock_translate_client_, IsTranslatableURL(GURL::EmptyGURL()))
+      .WillByDefault(Return(true));
+
+  translate_manager_->GetLanguageState().LanguageDetermined(
+      translate::kUnknownLanguageCode, true);
+
+  EXPECT_FALSE(translate_manager_->CanManuallyTranslate());
+}
+
 }  // namespace testing
 
 }  // namespace translate