Updated tag name validation to allow hyphens and relax requirements (#8304)

Author: glen-84

src/HotChocolate/Core/src/Types/Properties/TypeResources.resx

@@ -977,7 +977,7 @@ Type: `{0}`</value>
     <value>The specified type `{0}` is expected to be an output type.</value>
   </data>
   <data name="TagDirective_Name_NotValid" xml:space="preserve">
-    <value>The tag name must follow the GraphQL type name rules.</value>
+    <value>Tag names may only include alphanumeric characters (a-z, A-Z, 0-9), hyphens, and underscores.</value>
   </data>
   <data name="TagDirective_Descriptor_NotSupported" xml:space="preserve">
     <value>Tag is not supported on the specified descriptor.</value>

src/HotChocolate/Core/src/Types/Types/Directives/Tag.cs

@@ -1,7 +1,7 @@
 #nullable enable
 
+using System.Text.RegularExpressions;
 using HotChocolate.Properties;
-using HotChocolate.Utilities;
 
 namespace HotChocolate.Types;
 
@@ -47,7 +47,7 @@ interface Book {
       author: String!
     }
     """)]
-public sealed class Tag
+public sealed partial class Tag
 {
     /// <summary>
     /// Creates a new instance of <see cref="Tag"/>.
@@ -60,7 +60,9 @@ public sealed class Tag
     /// </exception>
     public Tag(string name)
     {
-        if (!name.IsValidGraphQLName())
+        ArgumentNullException.ThrowIfNull(name);
+
+        if (!ValidNameRegex().IsMatch(name))
         {
             throw new ArgumentException(
                 TypeResources.TagDirective_Name_NotValid,
@@ -75,4 +77,7 @@ public Tag(string name)
     /// </summary>
     [GraphQLDescription("The name of the tag.")]
     public string Name { get; }
+
+    [GeneratedRegex("^[a-zA-Z0-9_-]+$")]
+    private static partial Regex ValidNameRegex();
 }

src/HotChocolate/Core/test/Types.Tests/Types/Directives/TagDirectiveTests.cs

@@ -43,6 +43,65 @@ repeatable on SCHEMA | SCALAR | OBJECT | FIELD_DEFINITION |
         schema.MatchSnapshot();
     }
 
+    [Fact]
+    public async Task ValidNames()
+    {
+        var exception = await Record.ExceptionAsync(
+            async () => await new ServiceCollection()
+                .AddGraphQL()
+                .AddDocumentFromString(
+                    """
+                    type Query {
+                        field: String
+                            @tag(name: "tag")
+                            @tag(name: "TAG")
+                            @tag(name: "TAG_123")
+                            @tag(name: "tag_123")
+                            @tag(name: "tag-123")
+                    }
+
+                    directive @tag("The name of the tag." name: String!)
+                        repeatable on SCHEMA | SCALAR | OBJECT | FIELD_DEFINITION |
+                            ARGUMENT_DEFINITION | INTERFACE | UNION | ENUM | ENUM_VALUE |
+                            INPUT_OBJECT | INPUT_FIELD_DEFINITION
+                    """)
+                .UseField(_ => _ => default)
+                .BuildSchemaAsync());
+
+        Assert.Null(exception);
+    }
+
+    [Theory]
+    [InlineData("tag name")]
+    [InlineData("tag*")]
+    [InlineData("@TAG")]
+    [InlineData("tag=name")]
+    [InlineData("tagK")] // K = Kelvin Sign (U+212A)
+    public async Task InvalidNames(string tagName)
+    {
+        async Task Act() =>
+            await new ServiceCollection()
+                .AddGraphQL()
+                .AddDocumentFromString(
+                    $$"""
+                    type Query {
+                        field: String @tag(name: "{{tagName}}")
+                    }
+
+                    directive @tag("The name of the tag." name: String!)
+                        repeatable on SCHEMA | SCALAR | OBJECT | FIELD_DEFINITION |
+                            ARGUMENT_DEFINITION | INTERFACE | UNION | ENUM | ENUM_VALUE |
+                            INPUT_OBJECT | INPUT_FIELD_DEFINITION
+                    """)
+                .UseField(_ => _ => default)
+                .BuildSchemaAsync();
+
+        Assert.Equal(
+            "Tag names may only include alphanumeric characters (a-z, A-Z, 0-9), hyphens, and " +
+            "underscores. (Parameter 'name')",
+            (await Assert.ThrowsAsync<ArgumentException>(Act)).Message);
+    }
+
     [Tag("OnObjectType")]
     public class Query
     {