[browser] Revert to full NativeName by interop with JS

src/libraries/Common/src/Interop/Browser/Interop.Locale.cs

@@ -13,5 +13,7 @@ internal static unsafe partial class JsGlobalization
         internal static extern unsafe int GetFirstDayOfWeek(in string culture, out int exceptionalResult, out object result);
         [MethodImplAttribute(MethodImplOptions.InternalCall)]
         internal static extern unsafe int GetFirstWeekOfYear(in string culture, out int exceptionalResult, out object result);
+        [MethodImplAttribute(MethodImplOptions.InternalCall)]
+        internal static extern unsafe int GetLocaleInfo(in string locale, in string culture, char* buffer, int bufferLength, out int exceptionalResult, out object result);
     }
 }

src/libraries/System.Private.CoreLib/src/System/Globalization/CultureData.Browser.cs

@@ -10,13 +10,62 @@ namespace System.Globalization
     internal sealed partial class CultureData
     {
         private const int CULTURE_INFO_BUFFER_LEN = 50;
+        private const int LOCALE_INFO_BUFFER_LEN = 80;
+
+        private void JSInitLocaleInfo()
+        {
+            string? localeName = _sName;
+            if (string.IsNullOrEmpty(localeName))
+            {
+                _sEnglishLanguage = "Invariant Language";
+                _sNativeLanguage = _sEnglishLanguage;
+                _sEnglishCountry = "Invariant Country";
+                _sNativeCountry = _sEnglishCountry;
+                _sEnglishDisplayName = $"{_sEnglishLanguage} ({_sEnglishCountry})";
+                _sNativeDisplayName = _sEnglishDisplayName;
+            }
+            else
+            {
+                // English locale info
+                (_sEnglishLanguage, _sEnglishCountry) = JSGetLocaleInfo("en-US", localeName);
+                _sEnglishDisplayName = string.IsNullOrEmpty(_sEnglishCountry) ?
+                    _sEnglishLanguage :
+                    $"{_sEnglishLanguage} ({_sEnglishCountry})";
+                // Native locale info
+                (_sNativeLanguage, _sNativeCountry) = JSGetLocaleInfo(localeName, localeName);
+                _sNativeDisplayName = string.IsNullOrEmpty(_sNativeCountry) ?
+                    _sNativeLanguage :
+                    $"{_sNativeLanguage} ({_sNativeCountry})";
+            }
+        }
+
+        private unsafe (string, string) JSGetLocaleInfo(string cultureName, string localeName)
+        {
+            char* buffer = stackalloc char[LOCALE_INFO_BUFFER_LEN];
+            int resultLength = Interop.JsGlobalization.GetLocaleInfo(cultureName, localeName, buffer, LOCALE_INFO_BUFFER_LEN, out int exception, out object exResult);
+            if (exception != 0)
+                throw new Exception((string)exResult);
+            string result = new string(buffer, 0, resultLength);
+            string[] subresults = result.Split("##");
+            if (subresults.Length == 0)
+                throw new Exception("LocaleInfo recieved from the Browser is in incorrect format.");
+            if (subresults.Length == 1)
+                return (subresults[0], ""); // Neutral culture
+            return (subresults[0], subresults[1]);
+        }
+
+        private string JSGetNativeDisplayName(string localeName, string cultureName)
+        {
+            (string languageName, string countryName) = JSGetLocaleInfo(localeName, cultureName);
+            return string.IsNullOrEmpty(countryName) ?
+                    languageName :
+                    $"{languageName} ({countryName})";
+        }
 
         private static unsafe CultureData JSLoadCultureInfoFromBrowser(string localeName, CultureData culture)
         {
             char* buffer = stackalloc char[CULTURE_INFO_BUFFER_LEN];
-            int exception;
-            object exResult;
-            int resultLength = Interop.JsGlobalization.GetCultureInfo(localeName, buffer, CULTURE_INFO_BUFFER_LEN, out exception, out exResult);
+            int resultLength = Interop.JsGlobalization.GetCultureInfo(localeName, buffer, CULTURE_INFO_BUFFER_LEN, out int exception, out object exResult);
             if (exception != 0)
                 throw new Exception((string)exResult);
             string result = new string(buffer, 0, resultLength);

src/libraries/System.Private.CoreLib/src/System/Globalization/CultureData.Icu.cs

@@ -203,6 +203,12 @@ private string IcuGetLocaleInfo(LocaleStringData type, string? uiCultureName = n
             Debug.Assert(!GlobalizationMode.Invariant);
             Debug.Assert(!GlobalizationMode.UseNls);
             Debug.Assert(_sWindowsName != null, "[CultureData.IcuGetLocaleInfo] Expected _sWindowsName to be populated already");
+#if TARGET_BROWSER && !FEATURE_WASM_MANAGED_THREADS
+            if (type == LocaleStringData.NativeDisplayName)
+            {
+                return JSGetNativeDisplayName(_sWindowsName, uiCultureName ?? _sWindowsName);
+            }
+#endif
             return IcuGetLocaleInfo(_sWindowsName, type, uiCultureName);
         }
 
@@ -302,7 +308,14 @@ private unsafe string IcuGetTimeFormatString(bool shortFormat)
         // no support to lookup by region name, other than the hard-coded list in CultureData
         private static CultureData? IcuGetCultureDataFromRegionName() => null;
 
-        private string IcuGetLanguageDisplayName(string cultureName) => IcuGetLocaleInfo(cultureName, LocaleStringData.LocalizedDisplayName, CultureInfo.CurrentUICulture.Name);
+        private string IcuGetLanguageDisplayName(string cultureName)
+        {
+#if TARGET_BROWSER && !FEATURE_WASM_MANAGED_THREADS
+            return JSGetNativeDisplayName(CultureInfo.CurrentUICulture.Name, cultureName);
+#else
+            return IcuGetLocaleInfo(cultureName, LocaleStringData.LocalizedDisplayName, CultureInfo.CurrentUICulture.Name);
+#endif
+        }
 
         // use the fallback which is to return NativeName
         private static string? IcuGetRegionDisplayName() => null;

src/libraries/System.Private.CoreLib/src/System/Globalization/CultureData.cs

@@ -816,12 +816,13 @@ private static string NormalizeCultureName(string name, out bool isNeutralName)
             {
                 return null;
             }
-#if TARGET_BROWSER
+#if TARGET_BROWSER && !FEATURE_WASM_MANAGED_THREADS
             // populate fields for which ICU does not provide data in Hybrid mode
             if (GlobalizationMode.Hybrid && !string.IsNullOrEmpty(culture._sName))
             {
                 culture = JSLoadCultureInfoFromBrowser(culture._sName, culture);
             }
+            culture.JSInitLocaleInfo();
 #endif
 
             // We need _sWindowsName to be initialized to know if we're using overrides.

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

@@ -9,21 +9,22 @@ namespace System.Globalization.Tests
     public class CultureInfoEnglishName
     {
         // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
-        public static bool SupportFullGlobalizationData => PlatformDetection.IsNotUsingLimitedCultures || PlatformDetection.IsAndroid;
+        // Browser uses JS to get the NativeName that is missing in ICU (in the singlethreaded runtime only)
+        public static bool SupportFullGlobalizationData =>
+            (!PlatformDetection.IsWasi || PlatformDetection.IsHybridGlobalizationOnApplePlatform) && !PlatformDetection.IsWasmThreadingSupported;
 
         public static IEnumerable<object[]> EnglishName_TestData()
         {
             yield return new object[] { CultureInfo.CurrentCulture.Name, CultureInfo.CurrentCulture.EnglishName };
 
-            if (SupportFullGlobalizationData || PlatformDetection.IsHybridGlobalizationOnApplePlatform)
+            if (SupportFullGlobalizationData)
             {
                 yield return new object[] { "en-US", "English (United States)" };
                 yield return new object[] { "fr-FR", "French (France)" };
                 yield return new object[] { "uz-Cyrl", "Uzbek (Cyrillic)" };
             }
             else
             {
-                // Mobile / Browser ICU doesn't contain CultureInfo.EnglishName
                 yield return new object[] { "en-US", "en (US)" };
                 yield return new object[] { "fr-FR", "fr (FR)" };
             }
@@ -41,12 +42,12 @@ public void EnglishName(string name, string expected)
         public void ChineseNeutralEnglishName()
         {
             CultureInfo ci = new CultureInfo("zh-Hans");
-            Assert.True(ci.EnglishName == "Chinese (Simplified)" || ci.EnglishName == "Chinese, Simplified",
-                        $"'{ci.EnglishName}' not equal to `Chinese (Simplified)` nor `Chinese, Simplified`");
+            Assert.True(ci.EnglishName == "Chinese (Simplified)" || ci.EnglishName == "Chinese, Simplified" || ci.EnglishName == "Simplified Chinese",
+                        $"'{ci.EnglishName}' not equal to `Chinese (Simplified)` nor `Chinese, Simplified` nor `Simplified Chinese`");
 
             ci = new CultureInfo("zh-HanT");
-            Assert.True(ci.EnglishName == "Chinese (Traditional)" || ci.EnglishName == "Chinese, Traditional",
-                        $"'{ci.EnglishName}' not equal to `Chinese (Traditional)` nor `Chinese, Traditional`");
+            Assert.True(ci.EnglishName == "Chinese (Traditional)" || ci.EnglishName == "Chinese, Traditional" || ci.EnglishName == "Traditional Chinese",
+                        $"'{ci.EnglishName}' not equal to `Chinese (Traditional)` nor `Chinese, Traditional` nor `Traditional Chinese`");
         }
     }
 }

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

@@ -10,19 +10,31 @@ namespace System.Globalization.Tests
 {
     public class CultureInfoNames
     {
-        private static bool SupportFullIcuResources => (PlatformDetection.IsNotMobile && PlatformDetection.IsIcuGlobalization) || PlatformDetection.IsHybridGlobalizationOnApplePlatform;
+        // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
+        // Browser uses JS to get the NativeName that is missing in ICU (in the singlethreaded runtime only)
+        private static bool SupportFullIcuResources =>
+            !PlatformDetection.IsWasi && !PlatformDetection.IsAndroid && PlatformDetection.IsIcuGlobalization && !PlatformDetection.IsWasmThreadingSupported;
+
+        public static IEnumerable<object[]> SupportedCultures_TestData()
+        {
+            // Browser does not support all ICU locales but it uses JS to get the correct native name
+            if (!PlatformDetection.IsBrowser)
+            {
+                yield return new object[] { "aa", "aa", "Afar", "Afar" };
+                yield return new object[] { "aa-ER", "aa-ER", "Afar (Eritrea)", "Afar (Eritrea)" };
+            }
+            yield return new object[] { "en", "en", "English", "English" };
+            yield return new object[] { "en", "fr", "English", "anglais" };
+            yield return new object[] { "en-US", "en-US", "English (United States)", "English (United States)" };
+            yield return new object[] { "en-US", "fr-FR", "English (United States)", "anglais (\u00C9tats-Unis)" };
+            yield return new object[] { "en-US", "de-DE", "English (United States)", "Englisch (Vereinigte Staaten)" };
+            yield return new object[] { "", "en-US", "Invariant Language (Invariant Country)", "Invariant Language (Invariant Country)" };
+            yield return new object[] { "", "fr-FR", "Invariant Language (Invariant Country)", "Invariant Language (Invariant Country)" };
+            yield return new object[] { "", "", "Invariant Language (Invariant Country)", "Invariant Language (Invariant Country)" };
+        }
 
         [ConditionalTheory(nameof(SupportFullIcuResources))]
-        [InlineData("en", "en", "English", "English")]
-        [InlineData("en", "fr", "English", "anglais")]
-        [InlineData("aa", "aa", "Afar", "Afar")]
-        [InlineData("en-US", "en-US", "English (United States)", "English (United States)")]
-        [InlineData("en-US", "fr-FR", "English (United States)", "anglais (\u00C9tats-Unis)")]
-        [InlineData("en-US", "de-DE", "English (United States)", "Englisch (Vereinigte Staaten)")]
-        [InlineData("aa-ER", "aa-ER", "Afar (Eritrea)", "Afar (Eritrea)")]
-        [InlineData("", "en-US", "Invariant Language (Invariant Country)", "Invariant Language (Invariant Country)")]
-        [InlineData("", "fr-FR", "Invariant Language (Invariant Country)", "Invariant Language (Invariant Country)")]
-        [InlineData("", "", "Invariant Language (Invariant Country)", "Invariant Language (Invariant Country)")]
+        [MemberData(nameof(SupportedCultures_TestData))]
         public void TestDisplayName(string cultureName, string uiCultureName, string nativeName, string displayName)
         {
             using (new ThreadCultureChange(null, CultureInfo.GetCultureInfo(uiCultureName)))

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

@@ -8,20 +8,23 @@ namespace System.Globalization.Tests
 {
     public class CultureInfoNativeName
     {
+        // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
+        // Browser uses JS to get the NativeName that is missing in ICU (in the singlethreaded runtime only)
+        private static bool SupportFullIcuResources =>
+            (!PlatformDetection.IsWasi || PlatformDetection.IsHybridGlobalizationOnApplePlatform) && !PlatformDetection.IsWasmThreadingSupported;
+
         public static IEnumerable<object[]> NativeName_TestData()
         {
             yield return new object[] { CultureInfo.CurrentCulture.Name, CultureInfo.CurrentCulture.NativeName };
 
-            // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
-            if (PlatformDetection.IsNotUsingLimitedCultures || PlatformDetection.IsAndroid || PlatformDetection.IsHybridGlobalizationOnApplePlatform)
+            if (SupportFullIcuResources)
             {
                 yield return new object[] { "en-US", "English (United States)" };
                 yield return new object[] { "en-CA", "English (Canada)" };
                 yield return new object[] { "en-GB", "English (United Kingdom)" };
             }
             else
             {
-                // Mobile / Browser ICU doesn't contain CultureInfo.NativeName
                 yield return new object[] { "en-US", "en (US)" };
                 yield return new object[] { "en-CA", "en (CA)" };
             }

src/libraries/System.Runtime/tests/System.Globalization.Tests/System/Globalization/RegionInfoTests.cs

@@ -12,6 +12,11 @@ namespace System.Globalization.Tests
 {
     public class RegionInfoPropertyTests
     {
+        // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
+        // Browser uses JS to get the NativeName that is missing in ICU (in the singlethreaded runtime only)
+        public static bool SupportFullGlobalizationData =>
+            (!PlatformDetection.IsWasi || PlatformDetection.IsHybridGlobalizationOnApplePlatform) && !PlatformDetection.IsWasmThreadingSupported;
+
         [Theory]
         [InlineData("US", "US", "US")]
         [InlineData("IT", "IT", "IT")]
@@ -100,7 +105,6 @@ public void ValidateUsingCasedRegionName(string regionName)
         [Theory]
         [InlineData("en-US", "United States")]
         [OuterLoop("May fail on machines with multiple language packs installed")] // see https://github.com/dotnet/runtime/issues/30132
-        [ActiveIssue("https://github.com/dotnet/runtime/issues/45951", TestPlatforms.Browser)]
         public void DisplayName(string name, string expected)
         {
             using (new ThreadCultureChange(null, new CultureInfo(name)))
@@ -111,16 +115,14 @@ public void DisplayName(string name, string expected)
 
         public static IEnumerable<object[]> NativeName_TestData()
         {
-            // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
-            if (PlatformDetection.IsNotUsingLimitedCultures || PlatformDetection.IsAndroid || PlatformDetection.IsHybridGlobalizationOnApplePlatform)
+            if (SupportFullGlobalizationData)
             {
                 yield return new object[] { "GB", "United Kingdom" };
                 yield return new object[] { "SE", "Sverige" };
                 yield return new object[] { "FR", "France" };
             }
             else
             {
-                // Browser's ICU doesn't contain RegionInfo.NativeName
                 yield return new object[] { "GB", "GB" };
                 yield return new object[] { "SE", "SE" };
                 yield return new object[] { "FR", "FR" };
@@ -136,8 +138,7 @@ public void NativeName(string name, string expected)
 
         public static IEnumerable<object[]> EnglishName_TestData()
         {
-            // Android has its own ICU, which doesn't 100% map to UsingLimitedCultures
-            if (PlatformDetection.IsNotUsingLimitedCultures || PlatformDetection.IsAndroid || PlatformDetection.IsHybridGlobalizationOnApplePlatform)
+            if (SupportFullGlobalizationData)
             {
                 yield return new object[] { "en-US", new string[] { "United States" } };
                 yield return new object[] { "US", new string[] { "United States" } };
@@ -146,7 +147,6 @@ public static IEnumerable<object[]> EnglishName_TestData()
             }
             else
             {
-                // Browser's ICU doesn't contain RegionInfo.EnglishName
                 yield return new object[] { "en-US", new string[] { "US" } };
                 yield return new object[] { "US", new string[] { "US" } };
                 yield return new object[] { "zh-CN", new string[] { "CN" }};

src/mono/browser/runtime/corebindings.c

@@ -64,6 +64,7 @@ extern mono_bool mono_wasm_starts_with (MonoString **culture, const uint16_t* st
 extern mono_bool mono_wasm_ends_with (MonoString **culture, const uint16_t* str1, int32_t str1Length, const uint16_t* str2, int32_t str2Length, int32_t options, int *is_exception, MonoObject** ex_result);
 extern int mono_wasm_index_of (MonoString **culture, const uint16_t* str1, int32_t str1Length, const uint16_t* str2, int32_t str2Length, int32_t options, mono_bool fromBeginning, int *is_exception, MonoObject** ex_result);
 extern int mono_wasm_get_calendar_info (MonoString **culture, int32_t calendarId, const uint16_t* result, int32_t resultLength, int *is_exception, MonoObject** ex_result);
+extern int mono_wasm_get_locale_info (MonoString **locale, MonoString **culture, const uint16_t* result, int32_t resultLength, int *is_exception, MonoObject** ex_result);
 extern int mono_wasm_get_culture_info (MonoString **culture, const uint16_t* result, int32_t resultLength, int *is_exception, MonoObject** ex_result);
 extern int mono_wasm_get_first_day_of_week (MonoString **culture, int *is_exception, MonoObject** ex_result);
 extern int mono_wasm_get_first_week_of_year (MonoString **culture, int *is_exception, MonoObject** ex_result);
@@ -105,6 +106,7 @@ void bindings_initialize_internals (void)
 	mono_add_internal_call ("Interop/JsGlobalization::EndsWith", mono_wasm_ends_with);
 	mono_add_internal_call ("Interop/JsGlobalization::IndexOf", mono_wasm_index_of);
 	mono_add_internal_call ("Interop/JsGlobalization::GetCalendarInfo", mono_wasm_get_calendar_info);
+	mono_add_internal_call ("Interop/JsGlobalization::GetLocaleInfo", mono_wasm_get_locale_info);
 	mono_add_internal_call ("Interop/JsGlobalization::GetCultureInfo", mono_wasm_get_culture_info);
 	mono_add_internal_call ("Interop/JsGlobalization::GetFirstDayOfWeek", mono_wasm_get_first_day_of_week);
 	mono_add_internal_call ("Interop/JsGlobalization::GetFirstWeekOfYear", mono_wasm_get_first_week_of_year);

src/mono/browser/runtime/exports-binding.ts

@@ -22,7 +22,7 @@ import { mono_wasm_compare_string, mono_wasm_ends_with, mono_wasm_starts_with, m
 import { mono_wasm_get_calendar_info } from "./hybrid-globalization/calendar";
 
 import { mono_wasm_get_culture_info } from "./hybrid-globalization/culture-info";
-import { mono_wasm_get_first_day_of_week, mono_wasm_get_first_week_of_year } from "./hybrid-globalization/locales";
+import { mono_wasm_get_locale_info, mono_wasm_get_first_day_of_week, mono_wasm_get_first_week_of_year } from "./hybrid-globalization/locales";
 import { mono_wasm_browser_entropy } from "./crypto";
 import { mono_wasm_cancel_promise } from "./cancelable-promise";
 
@@ -107,6 +107,7 @@ export const mono_wasm_imports = [
     mono_wasm_index_of,
     mono_wasm_get_calendar_info,
     mono_wasm_get_culture_info,
+    mono_wasm_get_locale_info,
     mono_wasm_get_first_day_of_week,
     mono_wasm_get_first_week_of_year,
 ];

src/mono/browser/runtime/hybrid-globalization/helpers.ts

@@ -25,9 +25,9 @@ export function normalizeLocale(locale: string | null)
         const canonicalLocales = (Intl as any).getCanonicalLocales(locale.replace("_", "-"));
         return canonicalLocales.length > 0 ? canonicalLocales[0] : undefined;
     }
-    catch(ex: any)
+    catch
     {
-        throw new Error(`Get culture info failed for culture = ${locale} with error: ${ex}`);
+        return undefined;
     }
 }