Update RFC5646 data

LanguageData/rfc5646

@@ -1,4 +1,4 @@
-File-Date: 2025-05-15
+File-Date: 2025-06-23
 %%
 Type: language
 Subtag: aa
@@ -48555,6 +48555,12 @@ Comments: The subtag represents the old orthography of the Latvian
   language used during c. 1600s–1920s.
 %%
 Type: variant
+Subtag: viennese
+Description: The Viennese dialect of German
+Added: 2025-06-22
+Prefix: de
+%%
+Type: variant
 Subtag: vivaraup
 Description: Vivaro-Alpine
 Added: 2018-04-22

LanguageData/rfc5646.json

@@ -1,5 +1,5 @@
 {
-  "FileDate": "2025-05-15",
+  "FileDate": "2025-06-23",
   "RecordList": [
     {
       "Type": "Language",
@@ -94903,6 +94903,18 @@
         "lv"
       ]
     },
+    {
+      "Type": "Variant",
+      "SubTag": "viennese",
+      "Description": [
+        "The Viennese dialect of German"
+      ],
+      "Added": "2025-06-22",
+      "Comments": [],
+      "Prefix": [
+        "de"
+      ]
+    },
     {
       "Type": "Variant",
       "SubTag": "vivaraup",

LanguageTags/LanguageLookup.cs

@@ -116,6 +116,8 @@ public string GetIsoFromIetf(string languageTag)
             return match.iso;
         }
 
+        // TODO: Conditional parse and normalize before processing
+
         // Find a matching subtag record
         Rfc5646Data.Record subtag = _rfc5646.Find(languageTag, false);
         if (subtag != null)
@@ -168,6 +170,8 @@ public string GetIsoFromIetf(string languageTag)
 
     public bool IsMatch(string prefix, string languageTag)
     {
+        // TODO: Conditional parse and normalize before processing
+
         // https://r12a.github.io/app-subtags/
         // zh match: zh: zh, zh-Hant, zh-Hans, zh-cmn-Hant
         // zho not: zh

LanguageTags/rfc5646DataGen.cs

@@ -9,7 +9,7 @@ public partial class Rfc5646Data
     public static Rfc5646Data Create() =>
         new()
         {
-            FileDate = new DateOnly(2025, 5, 15),
+            FileDate = new DateOnly(2025, 6, 23),
             RecordList =
             [
                 new()
@@ -84453,6 +84453,15 @@ public static Rfc5646Data Create() =>
                     Prefix = [@"lv"],
                 },
                 new()
+                {
+                    Type = RecordType.Variant,
+                    SubTag = "viennese",
+                    Added = new DateOnly(2025, 6, 22),
+                    Description = [@"The Viennese dialect of German"],
+                    Comments = [],
+                    Prefix = [@"de"],
+                },
+                new()
                 {
                     Type = RecordType.Variant,
                     SubTag = "vivaraup",

LanguageTagsCreate/Program.cs

@@ -20,7 +20,7 @@ public static class Program
     private static async Task DownloadFileAsync(Uri uri, string fileName)
     {
         Log.Information("Downloading \"{Uri}\" to \"{FileName}\" ...", uri.ToString(), fileName);
-        Stream httpStream = await GetHttpClient().GetStreamAsync(uri);
+        await using Stream httpStream = await GetHttpClient().GetStreamAsync(uri);
         await using FileStream fileStream = File.Create(fileName);
         await httpStream.CopyToAsync(fileStream);
     }

README.md

@@ -166,9 +166,9 @@ IETF language tags are in the form of `[Language]-[Extended language]-[Script]-[
 
 Examples:
 
-- `pt` will match `pt` Portuguese, or `pt-BR` Brazilian Portuguese, or `pt-PT` European Portuguese.\
-- `pt-BR` will only match `pt-BR` Brazilian Portuguese.\
-- `zh` will match `zh` Chinese, or `zh-Hans` simplified Chinese, or `zh-Hant` for traditional Chinese, and other variants.\
+- `pt` will match `pt` Portuguese, or `pt-BR` Brazilian Portuguese, or `pt-PT` European Portuguese.
+- `pt-BR` will only match `pt-BR` Brazilian Portuguese\
+- `zh` will match `zh` Chinese, or `zh-Hans` simplified Chinese, or `zh-Hant` for traditional Chinese, and other variants.
 - `zh-Hans` will only match `zh-Hans` simplified Chinese.
 
 ```csharp