4 files changed, 16 insertions, 3 deletions

diff --git a/src/WixToolset.Extensibility/BaseResolverExtension.cs b/src/WixToolset.Extensibility/BaseResolverExtension.cs
index 16219e93..fcd2eed9 100644
--- a/src/WixToolset.Extensibility/BaseResolverExtension.cs
+++ b/src/WixToolset.Extensibility/BaseResolverExtension.cs
@@ -31,7 +31,7 @@ namespace WixToolset.Extensibility
             this.Messaging = context.ServiceProvider.GetService<IMessaging>();
         }
 
-        public virtual string ResolveFile(string source, IntermediateTupleDefinition tupleDefinition, SourceLineNumber sourceLineNumbers, BindStage bindStage)
+        public virtual ResolveFileResult ResolveFile(string source, IntermediateTupleDefinition tupleDefinition, SourceLineNumber sourceLineNumbers, BindStage bindStage)
         {
             return null;
         }
diff --git a/src/WixToolset.Extensibility/Data/ResolveFileResult.cs b/src/WixToolset.Extensibility/Data/ResolveFileResult.cs
new file mode 100644
index 00000000..5ac7c426
--- /dev/null
+++ b/src/WixToolset.Extensibility/Data/ResolveFileResult.cs
@@ -0,0 +1,13 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixToolset.Extensibility.Data
+{
+    using System.Collections.Generic;
+
+    public class ResolveFileResult
+    {
+        public string Path { get; set; }
+
+        public IEnumerable<string> CheckedPaths { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/src/WixToolset.Extensibility/ILibrarianExtension.cs b/src/WixToolset.Extensibility/ILibrarianExtension.cs
index 7319f8b9..b9f707e1 100644
--- a/src/WixToolset.Extensibility/ILibrarianExtension.cs
+++ b/src/WixToolset.Extensibility/ILibrarianExtension.cs
@@ -9,7 +9,7 @@ namespace WixToolset.Extensibility
     {
         void PreCombine(ILibraryContext context);
 
-        string Resolve(SourceLineNumber sourceLineNumber, IntermediateTupleDefinition tupleDefinition, string path);
+        ResolveFileResult ResolveFile(SourceLineNumber sourceLineNumber, IntermediateTupleDefinition tupleDefinition, string path);
 
         void PostCombine(Intermediate library);
     }
diff --git a/src/WixToolset.Extensibility/IResolverExtension.cs b/src/WixToolset.Extensibility/IResolverExtension.cs
index 152ef64a..36ada8f0 100644
--- a/src/WixToolset.Extensibility/IResolverExtension.cs
+++ b/src/WixToolset.Extensibility/IResolverExtension.cs
@@ -15,7 +15,7 @@ namespace WixToolset.Extensibility
         /// </summary>
         void PreResolve(IResolveContext context);
 
-        string ResolveFile(string source, IntermediateTupleDefinition tupleDefinition, SourceLineNumber sourceLineNumbers, BindStage bindStage);
+        ResolveFileResult ResolveFile(string source, IntermediateTupleDefinition tupleDefinition, SourceLineNumber sourceLineNumbers, BindStage bindStage);
 
         /// <summary>
         /// Called after all resolving occurs.