Expose FileTransfer as interface

This reduces the code in Extensiblity which is always a good thing.

1 files changed, 23 insertions, 0 deletions

diff --git a/src/WixToolset.Extensibility/Services/IBackendHelper.cs b/src/WixToolset.Extensibility/Services/IBackendHelper.cs
new file mode 100644
index 00000000..83f57e35
--- /dev/null
+++ b/src/WixToolset.Extensibility/Services/IBackendHelper.cs
@@ -0,0 +1,23 @@
+// 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 WixToolset.Data;
+    using WixToolset.Extensibility.Data;
+
+    /// <summary>
+    /// Interface provided to help backend extensions.
+    /// </summary>
+    public interface IBackendHelper
+    {
+        /// <summary>
+        /// Creates a file transfer and marks it redundant if the source and destination are identical.
+        /// </summary>
+        /// <param name="source">Source for the file transfer.</param>
+        /// <param name="destination">Destiation for the file transfer.</param>
+        /// <param name="move">Indicates whether to move or copy the source file.</param>
+        /// <param name="type">Type of file transfer to create.</param>
+        /// <param name="sourceLineNumbers">Optional source line numbers that requested the file transfer.</param>
+        IFileTransfer CreateFileTransfer(string source, string destination, bool move, FileTransferType type, SourceLineNumber sourceLineNumbers = null);
+    }
+}