Fix failing tests on Windows

Due to Foundation URL/path changes.

Author: jakepetroules

unittests/Swift/SwiftNinjaTests.swift

@@ -35,7 +35,7 @@ class SwiftNinjaTests: XCTestCase {
     let manifest = try NinjaManifest(
       path: manifestFile,
       workingDirectory: URL(fileURLWithPath: manifestFile)
-        .deletingLastPathComponent().path)
+        .deletingLastPathComponent().withUnsafeFileSystemRepresentation { try XCTUnwrap($0.map(String.init(cString:))) })
 
     let expectedRule = NinjaRule(
       name: "CMD", variables: ["command": "ls $in $out $statementvar",
@@ -60,7 +60,7 @@ class SwiftNinjaTests: XCTestCase {
     ])
   }
 
-  func testMissingRule() {
+  func testMissingRule() throws {
     let manifestFile = makeTemporaryFile("""
             build output: CMD input\n
             """)
@@ -79,18 +79,18 @@ class SwiftNinjaTests: XCTestCase {
     XCTAssertThrowsError(try NinjaManifest(
       path: manifestFile,
       workingDirectory: URL(fileURLWithPath: manifestFile)
-        .deletingLastPathComponent().path)) { error in
+        .deletingLastPathComponent().withUnsafeFileSystemRepresentation { try XCTUnwrap($0.map(String.init(cString:))) })) { error in
       guard case NinjaError.invalidManifest(let errors) = error else {
         XCTFail("Load error was not a NinjaError.invalidManifest")
         return
       }
       assertExpectedError(errors)
     }
 
-    let (manifest, errors) = NinjaManifest.createNonThrowing(
+    let (manifest, errors) = try NinjaManifest.createNonThrowing(
       path: manifestFile,
       workingDirectory: URL(fileURLWithPath: manifestFile)
-        .deletingLastPathComponent().path)
+        .deletingLastPathComponent().withUnsafeFileSystemRepresentation { try XCTUnwrap($0.map(String.init(cString:))) })
 
     XCTAssertNil(manifest.rules["CMD"])
     XCTAssertEqual(manifest.statements, [

unittests/TestSupport/XCTestCase+Extensions.swift

@@ -14,7 +14,13 @@ public extension XCTestCase {
     //
     // FIXME: Move to a shared location.
     func makeTemporaryFile(_ contents: String? = nil) -> String {
-        let directory = NSTemporaryDirectory()
+        var directory = NSTemporaryDirectory()
+        #if os(Windows)
+        // Workaround: https://github.com/apple/swift-corelibs-foundation/issues/5066
+        if directory.hasPrefix("/") {
+            directory.removeFirst()
+        }
+        #endif
         let filename = UUID().uuidString
         let fileURL = URL(fileURLWithPath: directory).appendingPathComponent(filename)
 
@@ -26,18 +32,27 @@ public extension XCTestCase {
             }
         }
 
+        let filePath = fileURL.withUnsafeFileSystemRepresentation {
+            if let path = $0.map(String.init(cString:)) {
+                return path
+            } else {
+                XCTFail("Could not convert file URL to path")
+                return String()
+            }
+        }
+
         addTeardownBlock {
             do {
                 let fileManager = FileManager.default
-                if fileManager.fileExists(atPath: fileURL.path) {
+                if fileManager.fileExists(atPath: filePath) {
                     try fileManager.removeItem(at: fileURL)
-                    XCTAssertFalse(fileManager.fileExists(atPath: fileURL.path))
+                    XCTAssertFalse(fileManager.fileExists(atPath: filePath))
                 }
             } catch {
                 XCTFail("Error while deleting temporary file: \(error)")
             }
         }
 
-        return fileURL.path
+        return filePath
     }
 }