Merge branch 'fix-root-creation' of https://github.com/aciidb0mb3r/swift-package-manager

Author: ddunbar

Sources/Basic/FileSystem.swift

@@ -386,6 +386,10 @@ public class InMemoryFileSystem: FileSystem {
     }
 
     public func createDirectory(_ path: AbsolutePath, recursive: Bool) throws {
+        // Ignore if client passes root.
+        guard !path.isRoot else {
+            return
+        }
         // Get the parent directory node.
         let parentPath = path.parentDirectory
         guard let parent = try getNode(parentPath) else {

Tests/Basic/FileSystemTests.swift

@@ -174,6 +174,11 @@ class FileSystemTests: XCTestCase {
 
     func testInMemoryCreateDirectory() {
         let fs = InMemoryFileSystem()
+        // Make sure root entry isn't created.
+        try! fs.createDirectory(AbsolutePath("/"), recursive: true)
+        let rootContents = try! fs.getDirectoryContents(.root)
+        XCTAssertEqual(rootContents, [])
+
         let subdir = AbsolutePath("/new-dir/subdir")
         try! fs.createDirectory(subdir, recursive: true)
         XCTAssert(fs.isDirectory(subdir))