Add overloads to support create-only Wixouts.

This prevents the .NET ZipArchive (and friends) from keeping the whole
thing in memory, to support updating when we don't need to update the
Wixout when building a binary Wixlib.

src/api/wix/WixToolset.Data/Intermediate.cs

@@ -246,6 +246,20 @@ public void Save(string path)
  }
  }
 
+ /// <summary>
+ /// Saves an intermediate that can only be written to to a path on disk.
+ /// </summary>
+ /// <param name="path">Path to save intermediate file to disk.</param>
+ public void SaveNew(string path)
+ {
+ Directory.CreateDirectory(Path.GetDirectoryName(Path.GetFullPath(path)));
+
+ using (var wixout = WixOutput.CreateNew(path))
+ {
+ this.Save(wixout);
+ }
+ }
+
  /// <summary>
  /// Saves an intermediate to a WixOutput.
  /// </summary>

src/api/wix/WixToolset.Data/WixOutput.cs

@@ -25,7 +25,7 @@ private WixOutput(Uri uri, ZipArchive archive, Stream stream)
  }
 
  /// <summary>
- /// 
+ ///
  /// </summary>
  public Uri Uri { get; }
 
@@ -189,7 +189,10 @@ public void ExtractEmbeddedFile(string embeddedId, string outputPath)
  /// <returns>Stream to the data of the file.</returns>
  public Stream CreateDataStream(string name)
  {
- this.DeleteExistingEntry(name);
+ if (this.archive.Mode == ZipArchiveMode.Update)
+ {
+ this.DeleteExistingEntry(name);
+ }
 
  var entry = this.archive.CreateEntry(name);
 
@@ -203,7 +206,10 @@ public Stream CreateDataStream(string name)
  /// <param name="path">Path to file on disk to include in the output.</param>
  public void ImportDataStream(string name, string path)
  {
- this.DeleteExistingEntry(name);
+ if (this.archive.Mode == ZipArchiveMode.Update)
+ {
+ this.DeleteExistingEntry(name);
+ }
 
  this.archive.CreateEntryFromFile(path, name, System.IO.Compression.CompressionLevel.Optimal);
  }
@@ -240,6 +246,26 @@ public string GetData(string name)
  }
  }
 
+ /// <summary>
+ /// Creates a new file structure on disk that can only be written to.
+ /// </summary>
+ /// <param name="path">Path to write file structure to.</param>
+ /// <returns>Newly created <c>WixOutput</c>.</returns>
+ internal static WixOutput CreateNew(string path)
+ {
+ var fullPath = Path.GetFullPath(path);
+
+ Directory.CreateDirectory(Path.GetDirectoryName(fullPath));
+
+ var uri = new Uri(fullPath);
+
+ var stream = File.Create(path);
+
+ var archive = new ZipArchive(stream, ZipArchiveMode.Create, leaveOpen: true);
+
+ return new WixOutput(uri, archive, stream);
+ }
+
  /// <summary>
  /// Disposes of the internal state of the file structure.
  /// </summary>

src/wix/WixToolset.Core/CommandLine/BuildCommand.cs

@@ -248,7 +248,7 @@ private void LibraryPhase(IReadOnlyCollection<Intermediate> intermediates, IRead
 
  if (!this.Messaging.EncounteredError)
  {
- result.Library.Save(outputPath);
+ result.Library.SaveNew(outputPath);
 
  this.LayoutFiles(result.TrackedFiles, null, cancellationToken);
  }