Improve discovery of executable methods to include implemented interfaces

Author: almostchristian

src/ConfigurationProcessor.Core/Implementation/Extensions.cs

@@ -113,7 +113,7 @@ public static void CallConfigurationMethods(
             IEnumerable? GetCollection(MethodInfo method)
             {
                var argValue = new ObjectArgumentValue(configSection!);
-               var collectionType = method.GetParameters().ElementAt(1).ParameterType;
+               var collectionType = method.GetParameters().ElementAt(method.IsStatic ? 1 : 0).ParameterType;
                return argValue.ConvertTo(method, collectionType, resolutionContext) as ICollection;
             }
 
@@ -185,15 +185,16 @@ private static List<MethodInfo> FindConfigurationExtensionMethods(
           MethodFilter? filter)
       {
          IReadOnlyCollection<Assembly> configurationAssemblies = resolutionContext.ConfigurationAssemblies;
-
+         var interfaces = configType.GetInterfaces();
          var candidateMethods = configurationAssemblies
              .SelectMany(a => SafeGetExportedTypes(a)
                  .Select(t => t.GetTypeInfo())
                  .Where(t => t.IsSealed && t.IsAbstract && !t.IsNested))
              .Union(new[] { configType.GetTypeInfo() })
+             .Concat(interfaces.Select(t => t.GetTypeInfo()))
              .SelectMany(t => candidateNames != null ? candidateNames.SelectMany(n => t.GetDeclaredMethods(n)) : t.DeclaredMethods)
              .Where(m => filter == null || filter(m, key))
-             .Where(m => !m.IsDefined(typeof(CompilerGeneratedAttribute), false) && m.IsPublic && ((m.IsStatic && m.IsDefined(typeof(ExtensionAttribute), false)) || m.DeclaringType == configType))
+             .Where(m => !m.IsDefined(typeof(CompilerGeneratedAttribute), false) && m.IsPublic && ((m.IsStatic && m.IsDefined(typeof(ExtensionAttribute), false)) || m.DeclaringType == configType || interfaces.Contains(m.DeclaringType)))
              .Where(m => !m.IsStatic || SafeGetParameters(m).ElementAtOrDefault(0)?.ParameterType.IsAssignableFrom(configType) == true) // If static method, checks that the first parameter is same as the extension type
              .ToList();
 

src/Directory.Build.props

@@ -5,7 +5,7 @@
    </PropertyGroup>
 
    <PropertyGroup>
-      <Version>1.3.0</Version>
+      <Version>1.4.0</Version>
       <FileVersion>$(Version).$([System.DateTime]::Now.ToString(yy))$([System.DateTime]::Now.DayOfYear.ToString(000))</FileVersion>
       <PackageVersion>$(Version)</PackageVersion>
       <InformationalVersion>$(FileVersion)-$(GIT_VERSION)</InformationalVersion>
@@ -23,6 +23,8 @@
       <PackageTags>dependencyinjection;configuration;ioc;di;</PackageTags>
       <PackageReadmeFile>README.md</PackageReadmeFile>
       <PackageReleaseNotes>
+v1.4.0
+   - Improve discovery of executable methods to include implemented interfaces
 v1.3.0
    - Add support for disambiguating overloads with different array types.
    - Prefer overloads with the most matching parameters

tests/TestDummies/IChildValue.cs

@@ -6,14 +6,11 @@
 
 namespace TestDummies
 {
-   public interface IChildValue
+   public interface IChildValue : IRootChildValue
    {
-      string Child { get; set; }
       Type ContextType { get; set; }
       Uri Location { get; set; }
       Delegate OnError { get; set; }
       TimeSpan? Time { get; set; }
-
-      void Reset();
    }
 }

tests/TestDummies/IRootChildValue.cs

@@ -0,0 +1,13 @@
+// -------------------------------------------------------------------------------------------------
+// Copyright (c) Integrated Health Information Systems Pte Ltd. All rights reserved.
+// -------------------------------------------------------------------------------------------------
+
+namespace TestDummies
+{
+   public interface IRootChildValue
+   {
+      string Child { get; set; }
+
+      void Reset();
+   }
+}