Fix invalid Unix locale to Flutter locale (BCP-47) mapping

shell/platform/linux/fl_engine.cc

@@ -86,29 +86,37 @@ static void parse_locale(const gchar* locale,
   // Locales are in the form "language[_territory][.codeset][@modifier]"
   gchar* match = strrchr(l, '@');
   if (match != nullptr) {
-    *modifier = g_strdup(match + 1);
+    if (modifier != nullptr) {
+      *modifier = g_strdup(match + 1);
+    }
     *match = '\0';
-  } else {
+  } else if (modifier != nullptr) {
     *modifier = nullptr;
   }
 
   match = strrchr(l, '.');
   if (match != nullptr) {
-    *codeset = g_strdup(match + 1);
+    if (codeset != nullptr) {
+      *codeset = g_strdup(match + 1);
+    }
     *match = '\0';
-  } else {
+  } else if (codeset != nullptr) {
     *codeset = nullptr;
   }
 
   match = strrchr(l, '_');
   if (match != nullptr) {
-    *territory = g_strdup(match + 1);
+    if (territory != nullptr) {
+      *territory = g_strdup(match + 1);
+    }
     *match = '\0';
-  } else {
+  } else if (territory != nullptr) {
     *territory = nullptr;
   }
 
-  *language = l;
+  if (language != nullptr) {
+    *language = l;
+  }
 }
 
 // Passes locale information to the Flutter engine.
@@ -118,29 +126,23 @@ static void setup_locales(FlEngine* self) {
   // Helper array to take ownership of the strings passed to Flutter.
   g_autoptr(GPtrArray) locale_strings = g_ptr_array_new_with_free_func(g_free);
   for (int i = 0; languages[i] != nullptr; i++) {
-    gchar *language, *territory, *codeset, *modifier;
-    parse_locale(languages[i], &language, &territory, &codeset, &modifier);
+    gchar *language, *territory;
+    parse_locale(languages[i], &language, &territory, nullptr, nullptr);
     if (language != nullptr) {
       g_ptr_array_add(locale_strings, language);
     }
     if (territory != nullptr) {
       g_ptr_array_add(locale_strings, territory);
     }
-    if (codeset != nullptr) {
-      g_ptr_array_add(locale_strings, codeset);
-    }
-    if (modifier != nullptr) {
-      g_ptr_array_add(locale_strings, modifier);
-    }
 
     FlutterLocale* locale =
         static_cast<FlutterLocale*>(g_malloc0(sizeof(FlutterLocale)));
     g_ptr_array_add(locales_array, locale);
     locale->struct_size = sizeof(FlutterLocale);
     locale->language_code = language;
     locale->country_code = territory;
-    locale->script_code = codeset;
-    locale->variant_code = modifier;
+    locale->script_code = nullptr;
+    locale->variant_code = nullptr;
   }
   FlutterLocale** locales =
       reinterpret_cast<FlutterLocale**>(locales_array->pdata);

shell/platform/linux/fl_engine_test.cc

@@ -359,4 +359,57 @@ TEST(FlEngineTest, DartEntrypointArgs) {
   EXPECT_TRUE(called);
 }
 
+TEST(FlEngineTest, Locales) {
+  gchar* initial_language = g_strdup(g_getenv("LANGUAGE"));
+  g_setenv("LANGUAGE", "de:en_US", TRUE);
+  g_autoptr(FlDartProject) project = fl_dart_project_new();
+
+  g_autoptr(FlEngine) engine = make_mock_engine_with_project(project);
+  FlutterEngineProcTable* embedder_api = fl_engine_get_embedder_api(engine);
+
+  bool called = false;
+  embedder_api->UpdateLocales = MOCK_ENGINE_PROC(
+      UpdateLocales, ([&called](auto engine, const FlutterLocale** locales,
+                                size_t locales_count) {
+        called = true;
+
+        EXPECT_EQ(locales_count, static_cast<size_t>(4));
+
+        EXPECT_STREQ(locales[0]->language_code, "de");
+        EXPECT_STREQ(locales[0]->country_code, nullptr);
+        EXPECT_STREQ(locales[0]->script_code, nullptr);
+        EXPECT_STREQ(locales[0]->variant_code, nullptr);
+
+        EXPECT_STREQ(locales[1]->language_code, "en");
+        EXPECT_STREQ(locales[1]->country_code, "US");
+        EXPECT_STREQ(locales[1]->script_code, nullptr);
+        EXPECT_STREQ(locales[1]->variant_code, nullptr);
+
+        EXPECT_STREQ(locales[2]->language_code, "en");
+        EXPECT_STREQ(locales[2]->country_code, nullptr);
+        EXPECT_STREQ(locales[2]->script_code, nullptr);
+        EXPECT_STREQ(locales[2]->variant_code, nullptr);
+
+        EXPECT_STREQ(locales[3]->language_code, "C");
+        EXPECT_STREQ(locales[3]->country_code, nullptr);
+        EXPECT_STREQ(locales[3]->script_code, nullptr);
+        EXPECT_STREQ(locales[3]->variant_code, nullptr);
+
+        return kSuccess;
+      }));
+
+  g_autoptr(GError) error = nullptr;
+  EXPECT_TRUE(fl_engine_start(engine, &error));
+  EXPECT_EQ(error, nullptr);
+
+  EXPECT_TRUE(called);
+
+  if (initial_language) {
+    g_setenv("LANGUAGE", initial_language, TRUE);
+  } else {
+    g_unsetenv("LANGUAGE");
+  }
+  g_free(initial_language);
+}
+
 // NOLINTEND(clang-analyzer-core.StackAddressEscape)