8 files changed, 70 insertions, 78 deletions

diff --git a/src/api/wix/WixToolset.Data/ErrorMessages.cs b/src/api/wix/WixToolset.Data/ErrorMessages.cs
index 40378a2e..77ce73aa 100644
--- a/src/api/wix/WixToolset.Data/ErrorMessages.cs
+++ b/src/api/wix/WixToolset.Data/ErrorMessages.cs
@@ -651,7 +651,8 @@ namespace WixToolset.Data
         public static Message FileNotFound(SourceLineNumber sourceLineNumbers, string file, string fileType, IEnumerable<string> checkedPaths)
         {
             var combinedCheckedPaths = String.Join(", ", checkedPaths);
-            return Message(sourceLineNumbers, Ids.FileNotFound, "The system cannot find the file '{0}' with type '{1}'. The following paths were checked: {2}", file, fileType, combinedCheckedPaths);
+            var withType = String.IsNullOrEmpty(fileType) ? String.Empty : $" with type '{fileType}'";
+            return Message(sourceLineNumbers, Ids.FileNotFound, "The system cannot find the file '{0}'{1}. The following paths were checked: {2}", file, withType, combinedCheckedPaths);
         }
 
         public static Message FileOrDirectoryPathRequired(string parameter)
diff --git a/src/api/wix/WixToolset.Data/Symbols/WixPatchBaselineSymbol.cs b/src/api/wix/WixToolset.Data/Symbols/WixPatchBaselineSymbol.cs
index d7295424..cbf51e2e 100644
--- a/src/api/wix/WixToolset.Data/Symbols/WixPatchBaselineSymbol.cs
+++ b/src/api/wix/WixToolset.Data/Symbols/WixPatchBaselineSymbol.cs
@@ -14,7 +14,6 @@ namespace WixToolset.Data
                 new IntermediateFieldDefinition(nameof(WixPatchBaselineSymbolFields.ValidationFlags), IntermediateFieldType.Number),
                 new IntermediateFieldDefinition(nameof(WixPatchBaselineSymbolFields.BaselineFile), IntermediateFieldType.Path),
                 new IntermediateFieldDefinition(nameof(WixPatchBaselineSymbolFields.UpdateFile), IntermediateFieldType.Path),
-                new IntermediateFieldDefinition(nameof(WixPatchBaselineSymbolFields.TransformFile), IntermediateFieldType.Path),
             },
             typeof(WixPatchBaselineSymbol));
     }
@@ -28,7 +27,6 @@ namespace WixToolset.Data.Symbols
         ValidationFlags,
         BaselineFile,
         UpdateFile,
-        TransformFile,
     }
 
     public class WixPatchBaselineSymbol : IntermediateSymbol
@@ -66,11 +64,5 @@ namespace WixToolset.Data.Symbols
             get => this.Fields[(int)WixPatchBaselineSymbolFields.UpdateFile].AsPath();
             set => this.Set((int)WixPatchBaselineSymbolFields.UpdateFile, value);
         }
-
-        public IntermediateFieldPathValue TransformFile
-        {
-            get => this.Fields[(int)WixPatchBaselineSymbolFields.TransformFile].AsPath();
-            set => this.Set((int)WixPatchBaselineSymbolFields.TransformFile, value);
-        }
     }
 }
diff --git a/src/api/wix/WixToolset.Extensibility/Data/IBindContext.cs b/src/api/wix/WixToolset.Extensibility/Data/IBindContext.cs
index 671da292..9d663c65 100644
--- a/src/api/wix/WixToolset.Extensibility/Data/IBindContext.cs
+++ b/src/api/wix/WixToolset.Extensibility/Data/IBindContext.cs
@@ -18,6 +18,11 @@ namespace WixToolset.Extensibility.Data
         IServiceProvider ServiceProvider { get; }
 
         /// <summary>
+        /// Bind paths used during resolution.
+        /// </summary>
+        IReadOnlyCollection<IBindPath> BindPaths { get; set; }
+
+        /// <summary>
         /// Counnt of threads to use in cabbing.
         /// </summary>
         int CabbingThreadCount { get; set; }
diff --git a/src/api/wix/WixToolset.Extensibility/Data/IFileFacade.cs b/src/api/wix/WixToolset.Extensibility/Data/IFileFacade.cs
index fea00d4e..8a9e3fee 100644
--- a/src/api/wix/WixToolset.Extensibility/Data/IFileFacade.cs
+++ b/src/api/wix/WixToolset.Extensibility/Data/IFileFacade.cs
@@ -5,34 +5,13 @@ namespace WixToolset.Extensibility.Data
     using System.Collections.Generic;
     using WixToolset.Data;
     using WixToolset.Data.Symbols;
-    using WixToolset.Data.WindowsInstaller.Rows;
 
     /// <summary>
-    /// Interface that provides a common facade over <c>FileSymbol</c> and <c>FileRow</c>.
+    /// Interface that provides a common facade over file information.
     /// </summary>
     public interface IFileFacade
     {
         /// <summary>
-        /// Reference to assembly application for this file.
-        /// </summary>
-        string AssemblyApplicationFileRef { get; }
-
-        /// <summary>
-        /// Reference to assembly manifest for this file.
-        /// </summary>
-        string AssemblyManifestFileRef { get; }
-
-        /// <summary>
-        /// List of assembly name values in the file.
-        /// </summary>
-        List<MsiAssemblyNameSymbol> AssemblyNames { get; set; }
-
-        /// <summary>
-        /// Optionally indicates what sort of assembly the file is.
-        /// </summary>
-        AssemblyType? AssemblyType { get; }
-
-        /// <summary>
         /// Component containing the file.
         /// </summary>
         string ComponentRef { get; }
@@ -58,21 +37,6 @@ namespace WixToolset.Extensibility.Data
         int FileSize { get; set; }
 
         /// <summary>
-        /// Indicates whether the file came from a merge module.
-        /// </summary>
-        bool FromModule { get; }
-
-        /// <summary>
-        /// Indicates whether the file came from a transform.
-        /// </summary>
-        bool FromTransform { get; }
-
-        /// <summary>
-        /// Hash symbol of the file.
-        /// </summary>
-        MsiFileHashSymbol Hash { get; set; }
-
-        /// <summary>
         /// Underlying identifier of the file.
         /// </summary>
         Identifier Identifier { get; }
@@ -118,9 +82,13 @@ namespace WixToolset.Extensibility.Data
         string Version { get; set; }
 
         /// <summary>
-        /// Gets the underlying <c>FileRow</c> if one is present.
+        /// Calculated hash of the file.
+        /// </summary>
+        MsiFileHashSymbol MsiFileHashSymbol { get; set; }
+
+        /// <summary>
+        /// Assembly names found in the file.
         /// </summary>
-        /// <returns><c>FileRow</c> if one is present, otherwise throws.</returns>
-        FileRow GetFileRow();
+        ICollection<MsiAssemblyNameSymbol> AssemblyNameSymbols { get; }
     }
 }
diff --git a/src/api/wix/WixToolset.Extensibility/Data/IWindowsInstallerDecompileContext.cs b/src/api/wix/WixToolset.Extensibility/Data/IWindowsInstallerDecompileContext.cs
index 27d30a5a..7b974942 100644
--- a/src/api/wix/WixToolset.Extensibility/Data/IWindowsInstallerDecompileContext.cs
+++ b/src/api/wix/WixToolset.Extensibility/Data/IWindowsInstallerDecompileContext.cs
@@ -63,11 +63,6 @@ namespace WixToolset.Extensibility.Data
         string IntermediateFolder { get; set; }
 
         /// <summary>
-        /// Gets or sets whether the decompiler admin image.
-        /// </summary>
-        bool IsAdminImage { get; set; }
-
-        /// <summary>
         /// Gets or sets where to output the result.
         /// </summary>
         string OutputPath { get; set; }
diff --git a/src/api/wix/WixToolset.Extensibility/Services/IBackendHelper.cs b/src/api/wix/WixToolset.Extensibility/Services/IBackendHelper.cs
index eff42b99..8bb1b2d6 100644
--- a/src/api/wix/WixToolset.Extensibility/Services/IBackendHelper.cs
+++ b/src/api/wix/WixToolset.Extensibility/Services/IBackendHelper.cs
@@ -5,8 +5,6 @@ namespace WixToolset.Extensibility.Services
     using System;
     using System.Collections.Generic;
     using WixToolset.Data;
-    using WixToolset.Data.Symbols;
-    using WixToolset.Data.WindowsInstaller.Rows;
     using WixToolset.Extensibility.Data;
 
     /// <summary>
@@ -15,28 +13,6 @@ namespace WixToolset.Extensibility.Services
     public interface IBackendHelper : ILayoutServices
     {
         /// <summary>
-        /// Creates a file facade from a <c>FileSymbol</c> and possible <c>AssemblySymbol</c>.
-        /// </summary>
-        /// <param name="file"><c>FileSymbol</c> backing the facade.</param>
-        /// <param name="assembly"><c>AssemblySymbol</c> backing the facade.</param>
-        /// <returns></returns>
-        IFileFacade CreateFileFacade(FileSymbol file, AssemblySymbol assembly);
-
-        /// <summary>
-        /// Creates a file facade from a File row.
-        /// </summary>
-        /// <param name="fileRow"><c>FileRow</c> </param>
-        /// <returns>New <c>IFileFacade</c>.</returns>
-        IFileFacade CreateFileFacade(FileRow fileRow);
-
-        /// <summary>
-        /// Creates a file facade from a Merge Module's File symbol.
-        /// </summary>
-        /// <param name="fileSymbol"><c>FileSymbol</c> created from a Merge Module.</param>
-        /// <returns>New <c>IFileFacade</c>.</returns>
-        IFileFacade CreateFileFacadeFromMergeModule(FileSymbol fileSymbol);
-
-        /// <summary>
         /// Creates a MSI compatible GUID.
         /// </summary>
         /// <returns>Creates an uppercase GUID with braces.</returns>
diff --git a/src/api/wix/WixToolset.Extensibility/Services/IFileResolver.cs b/src/api/wix/WixToolset.Extensibility/Services/IFileResolver.cs
new file mode 100644
index 00000000..2804cc28
--- /dev/null
+++ b/src/api/wix/WixToolset.Extensibility/Services/IFileResolver.cs
@@ -0,0 +1,38 @@
+// 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.Services
+{
+    using System.Collections.Generic;
+    using WixToolset.Data;
+    using WixToolset.Extensibility.Data;
+
+    /// <summary>
+    /// Interface to resolve file paths using extensions and bind paths.
+    /// </summary>
+    public interface IFileResolver
+    {
+        /// <summary>
+        /// Resolves the source path of a file using binder extensions.
+        /// </summary>
+        /// <param name="source">Original source value.</param>
+        /// <param name="librarianExtensions">Extensions used to resolve the file path.</param>
+        /// <param name="bindPaths">Collection of bind paths for the binding stage.</param>
+        /// <param name="sourceLineNumbers">Optional source line of source file being resolved.</param>
+        /// <param name="symbolDefinition">Optional type of source file being resolved.</param>
+        /// <returns>Should return a valid path for the stream to be imported.</returns>
+        string ResolveFile(string source, IEnumerable<ILibrarianExtension> librarianExtensions, IEnumerable<IBindPath> bindPaths, SourceLineNumber sourceLineNumbers, IntermediateSymbolDefinition symbolDefinition);
+
+        /// <summary>
+        /// Resolves the source path of a file using binder extensions.
+        /// </summary>
+        /// <param name="source">Original source value.</param>
+        /// <param name="resolverExtensions">Extensions used to resolve the file path.</param>
+        /// <param name="bindPaths">Collection of bind paths for the binding stage.</param>
+        /// <param name="bindStage">The binding stage used to determine what collection of bind paths will be used</param>
+        /// <param name="sourceLineNumbers">Optional source line of source file being resolved.</param>
+        /// <param name="symbolDefinition">Optional type of source file being resolved.</param>
+        /// <param name="alreadyCheckedPaths">Optional collection of paths already checked.</param>
+        /// <returns>Should return a valid path for the stream to be imported.</returns>
+        string ResolveFile(string source, IEnumerable<IResolverExtension> resolverExtensions, IEnumerable<IBindPath> bindPaths, BindStage bindStage, SourceLineNumber sourceLineNumbers, IntermediateSymbolDefinition symbolDefinition, IEnumerable<string> alreadyCheckedPaths = null);
+    }
+}
diff --git a/src/api/wix/WixToolset.Extensibility/Services/IWindowsInstallerBackendHelper.cs b/src/api/wix/WixToolset.Extensibility/Services/IWindowsInstallerBackendHelper.cs
index 81325131..2216e957 100644
--- a/src/api/wix/WixToolset.Extensibility/Services/IWindowsInstallerBackendHelper.cs
+++ b/src/api/wix/WixToolset.Extensibility/Services/IWindowsInstallerBackendHelper.cs
@@ -3,7 +3,10 @@
 namespace WixToolset.Extensibility.Services
 {
     using WixToolset.Data;
+    using WixToolset.Data.Symbols;
     using WixToolset.Data.WindowsInstaller;
+    using WixToolset.Data.WindowsInstaller.Rows;
+    using WixToolset.Extensibility.Data;
 
     /// <summary>
     /// Interface provided to help Windows Installer backend extensions.
@@ -11,6 +14,20 @@ namespace WixToolset.Extensibility.Services
     public interface IWindowsInstallerBackendHelper : IBackendHelper
     {
         /// <summary>
+        /// Creates a file facade from a <c>FileSymbol</c>.
+        /// </summary>
+        /// <param name="file"><c>FileSymbol</c> backing the facade.</param>
+        /// <returns></returns>
+        IFileFacade CreateFileFacade(FileSymbol file);
+
+        /// <summary>
+        /// Creates a file facade from a File row.
+        /// </summary>
+        /// <param name="fileRow"><c>FileRow</c></param>
+        /// <returns>New <c>IFileFacade</c>.</returns>
+        IFileFacade CreateFileFacade(FileRow fileRow);
+
+        /// <summary>
         /// Creates a <see cref="Row"/> in the specified table.
         /// </summary>
         /// <param name="section">Parent section.</param>