[iOS] Retrieve device locale in full (specific) format from ObjectiveC APIs (#111032)

Author: matouskozak

src/libraries/System.Runtime/tests/System.Globalization.Tests/CultureInfo/CultureInfoCurrentCulture.cs

@@ -44,6 +44,15 @@ public void CurrentCulture_Default_Not_Invariant()
             Assert.NotEqual(CultureInfo.CurrentUICulture, CultureInfo.InvariantCulture);
         }
 
+        [Fact]
+        [PlatformSpecific(TestPlatforms.OSX | TestPlatforms.iOS | TestPlatforms.MacCatalyst | TestPlatforms.tvOS)]
+        [SkipOnPlatform(TestPlatforms.iOS | TestPlatforms.MacCatalyst | TestPlatforms.tvOS, "https://github.com/dotnet/runtime/issues/111501")]
+        public void CurrentCulture_Default_Is_Specific()
+        {
+            // On OSX-like platforms, the current culture taken from default system culture should be specific.
+            Assert.False(CultureInfo.CurrentCulture.IsNeutralCulture);
+        }
+
         [Fact]
         public void CurrentCulture_Set_Null_ThrowsArgumentNullException()
         {

src/native/libs/System.Globalization.Native/pal_locale.m

@@ -786,21 +786,14 @@ int32_t GlobalizationNative_GetLocalesNative(UChar* value, int32_t length)
     }
 }
 
-static NSString* GetBaseName(NSString *localeIdentifier)
-{
-    NSLocale *locale = [[NSLocale alloc] initWithLocaleIdentifier:localeIdentifier];
-    NSString *languageCode = [locale objectForKey:NSLocaleLanguageCode];
-    return languageCode;
-}
-
 const char* GlobalizationNative_GetDefaultLocaleNameNative(void)
 {
     @autoreleasepool
     {
         if (NSLocale.preferredLanguages.count > 0)
         {
             NSString *preferredLanguage = [NSLocale.preferredLanguages objectAtIndex:0];
-            return strdup([GetBaseName(preferredLanguage) UTF8String]);
+            return strdup([preferredLanguage UTF8String]);
         }
         else
         {
@@ -821,7 +814,7 @@ int32_t GlobalizationNative_GetLocalesNative(UChar* value, int32_t length)
                 localeName = currentLocale.localeIdentifier;
             }
 
-            return strdup([GetBaseName(localeName) UTF8String]);
+            return strdup([localeName UTF8String]);
         }
     }
 }