PackageLoading: enable the manifest VFS on Windows

Ensure that the path string is escaped when emitting the paths. The VFS
paths are serialised as either JSON or YAML, both of which require the
path string be escaped.

Author: compnerd

Sources/PackageLoading/ManifestLoader.swift

@@ -538,17 +538,11 @@ public final class ManifestLoader: ManifestLoaderProtocol {
                 let manifestTempFilePath = tempDir.appending("manifest.swift")
                 try localFileSystem.writeFileContents(manifestTempFilePath, bytes: ByteString(manifestPreamble.contents + manifestContents))
 
-                #if os(Windows)
-                // On Windows, we seem to have issues with the VFS overlay, so let's disable it for now.
-                let effectiveManifestPath = manifestTempFilePath
-                let vfsOverlayTempFilePath: AbsolutePath? = nil
-                #else
-                let effectiveManifestPath = manifestPath
                 let vfsOverlayTempFilePath = tempDir.appending("vfs.yaml")
                 try VFSOverlay(roots: [
-                    VFSOverlay.File(name: manifestPath.pathString, externalContents: manifestTempFilePath.pathString)
+                    VFSOverlay.File(name: manifestPath._nativePathString(escaped: true),
+                                    externalContents: manifestTempFilePath._nativePathString(escaped: true))
                 ]).write(to: vfsOverlayTempFilePath, fileSystem: localFileSystem)
-                #endif
 
                 validateImports(manifestPath: manifestTempFilePath, toolsVersion: toolsVersion, callbackQueue: callbackQueue) { result in
                     dispatchPrecondition(condition: .onQueue(callbackQueue))
@@ -557,7 +551,7 @@ public final class ManifestLoader: ManifestLoaderProtocol {
                         try result.get()
 
                         try self.evaluateManifest(
-                            at: effectiveManifestPath,
+                            at: manifestPath,
                             vfsOverlayPath: vfsOverlayTempFilePath,
                             packageIdentity: packageIdentity,
                             toolsVersion: toolsVersion,