Add a possibility to specify namespace suffix without a need to specify the whole namespace name

AutomaticInterface/AutomaticInterface/AutomaticInterface.csproj

@@ -24,7 +24,7 @@
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
     <EnableNETAnalyzers>True</EnableNETAnalyzers>
     <AnalysisLevel>latest-Recommended</AnalysisLevel>
-    <Version>5.2.6</Version>
+    <Version>5.3.0</Version>
     <PackageReadmeFile>README.md</PackageReadmeFile>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <NoWarn>1701;1702;NU5128</NoWarn>

AutomaticInterface/AutomaticInterface/GeneratedSymbolDetails.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics;
 using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
@@ -16,9 +17,8 @@ ClassDeclarationSyntax classSyntax
     /// to the containing namespace of the type symbol.
     /// </summary>
     public string NamespaceName { get; } =
-        PrepareValue(
+        PrepareNamespaceName(
             generationAttribute,
-            AutomaticInterfaceGenerator.NamespaceParameterName,
             typeSymbol.ContainingNamespace.ToDisplayString()
         );
 
@@ -78,4 +78,19 @@ private static T PrepareValue<T>(AttributeData? generationAttribute, string key,
 
         return defaultValue;
     }
+
+    private static string PrepareNamespaceName(AttributeData? generationAttribute, string containingNamespaceName)
+    {
+        var namespacePattern = PrepareValue(
+            generationAttribute,
+            AutomaticInterfaceGenerator.NamespaceParameterName,
+            containingNamespaceName
+        );
+
+        Debug.Assert(namespacePattern != null);
+
+        var namespaceName = namespacePattern!.Replace("*", containingNamespaceName);
+
+        return namespaceName;
+    }
 }

AutomaticInterface/AutomaticInterface/RegisterAttributesExtensions.cs

@@ -32,7 +32,7 @@ internal sealed class {{AutomaticInterfaceGenerator.DefaultAttributeName}}Attrib
                             /// <summary>
                             /// Use source generator to automatically create a Interface from this class
                             /// </summary>
-                            /// <param name="namespaceName">Namespace name for the generated interface. Defaults to the same namespace as the class.</param>
+                            /// <param name="namespaceName">Namespace name for the generated interface. Defaults to the same namespace as the class. The '*' character may be used as a placeholder for the containing type's namespace, allowing you to specify only a prefix for the target namespace instead of its full name.</param>
                             /// <param name="interfaceName">Interface name for the generated interface. Defaults to an interface version of the class name, e.g ExampleClass -> IExampleClass.</param>
                             /// <param name="asInternal">If true, the generated interface will be internal, otherwise public</param>
                             internal {{AutomaticInterfaceGenerator.DefaultAttributeName}}Attribute(string {{AutomaticInterfaceGenerator.NamespaceParameterName}} = default(string), string {{AutomaticInterfaceGenerator.InterfaceParameterName}} = default(string), bool {{AutomaticInterfaceGenerator.AsInternalParameterName}} = false) { }

AutomaticInterface/Tests/Misc/Misc.CustomNameSpaceWithWildcardWithinBrackedNamespace.verified.txt

@@ -0,0 +1,18 @@
+//--------------------------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//
+//     Changes to this file may cause incorrect behavior and will be lost if the code is regenerated.
+// </auto-generated>
+//--------------------------------------------------------------------------------------------------
+
+namespace AutomaticInterfaceExample.CustomNameSpaceSuffix
+{
+    [global::System.CodeDom.Compiler.GeneratedCode("AutomaticInterface", "")]
+    public partial interface IDemoClass
+    {
+        /// <inheritdoc cref="AutomaticInterfaceExample.DemoClass.DemoMethod()" />
+        int DemoMethod();
+
+    }
+}

AutomaticInterface/Tests/Misc/Misc.CustomNameSpaceWithWildcardWithinFileNamespace.verified.txt

@@ -0,0 +1,18 @@
+//--------------------------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//
+//     Changes to this file may cause incorrect behavior and will be lost if the code is regenerated.
+// </auto-generated>
+//--------------------------------------------------------------------------------------------------
+
+namespace AutomaticInterfaceExample.CustomNameSpaceSuffix
+{
+    [global::System.CodeDom.Compiler.GeneratedCode("AutomaticInterface", "")]
+    public partial interface IDemoClass
+    {
+        /// <inheritdoc cref="AutomaticInterfaceExample.DemoClass.DemoMethod()" />
+        int DemoMethod();
+
+    }
+}

AutomaticInterface/Tests/Misc/Misc.cs

@@ -365,6 +365,48 @@ class DemoClass
         await Verify(Infrastructure.GenerateCode(code));
     }
 
+
+    [Fact]
+    public async Task CustomNameSpaceWithWildcardWithinBrackedNamespace()
+    {
+        const string code = """
+
+            using AutomaticInterface;
+
+            namespace AutomaticInterfaceExample
+            {
+                [GenerateAutomaticInterface("*.CustomNameSpaceSuffix")]
+                class DemoClass
+                {
+                   public int DemoMethod() => 5;
+                }
+            }
+
+            """;
+
+        await Verify(Infrastructure.GenerateCode(code));
+    }
+
+    [Fact]
+    public async Task CustomNameSpaceWithWildcardWithinFileNamespace()
+    {
+        const string code = """
+
+            using AutomaticInterface;
+
+            namespace AutomaticInterfaceExample;
+
+            [GenerateAutomaticInterface("*.CustomNameSpaceSuffix")]
+            class DemoClass
+            {
+                public int DemoMethod() => 5;
+            }
+
+            """;
+
+        await Verify(Infrastructure.GenerateCode(code));
+    }
+
     [Fact]
     public async Task AsInternal()
     {