Merge pull request #2548 from spevans/pr_process_current_directory2

Process: Match Darwin more closely for handling of .currentDirectoryPath and .currentDirectoryURL

Author: spevans

Foundation/Process.swift

@@ -243,14 +243,17 @@ open class Process: NSObject {
         }
     }
 
-    private var _currentDirectoryURL: URL? = URL(fileURLWithPath: FileManager.default.currentDirectoryPath, isDirectory: true)
+    private var _currentDirectoryPath = FileManager.default.currentDirectoryPath
     open var currentDirectoryURL: URL? {
-        get { _currentDirectoryURL }
+        get { _currentDirectoryPath == "" ? nil : URL(fileURLWithPath: _currentDirectoryPath, isDirectory: true) }
         set {
-            guard let url = newValue, url.isFileURL else {
-                fatalError("non-file URL argument")
+            // Setting currentDirectoryURL to nil resets to the current directory
+            if let url = newValue {
+                guard url.isFileURL else { fatalError("non-file URL argument") }
+                _currentDirectoryPath = url.path
+            } else {
+                _currentDirectoryPath = FileManager.default.currentDirectoryPath
             }
-            _currentDirectoryURL = url
         }
     }
 
@@ -265,8 +268,8 @@ open class Process: NSObject {
 
     @available(*, deprecated, renamed: "currentDirectoryURL")
     open var currentDirectoryPath: String {
-        get { return currentDirectoryURL!.path }
-        set { currentDirectoryURL = URL(fileURLWithPath: newValue) }
+        get { _currentDirectoryPath }
+        set { _currentDirectoryPath = newValue }
     }
 
     // Standard I/O channels; could be either a FileHandle or a Pipe
@@ -583,8 +586,9 @@ open class Process: NSObject {
             CFSocketCreateRunLoopSource(kCFAllocatorDefault, socket, 0)
         CFRunLoopAddSource(managerThreadRunLoop?._cfRunLoop, source, kCFRunLoopDefaultMode)
 
+        let workingDirectory = currentDirectoryURL?.path ?? FileManager.default.currentDirectoryPath
         try quoteWindowsCommandLine(command).withCString(encodedAs: UTF16.self) { wszCommandLine in
-          try currentDirectoryURL.path.withCString(encodedAs: UTF16.self) { wszCurrentDirectory in
+          try workingDirectory.withCString(encodedAs: UTF16.self) { wszCurrentDirectory in
             try szEnvironment.withCString(encodedAs: UTF16.self) { wszEnvironment in
               if !CreateProcessW(nil, UnsafeMutablePointer<WCHAR>(mutating: wszCommandLine),
                                  nil, nil, true,

TestFoundation/TestProcess.swift

@@ -596,6 +596,38 @@ class TestProcess : XCTestCase {
         let process = Process()
         XCTAssertNil(process.executableURL)
         XCTAssertNotNil(process.currentDirectoryURL)
+
+        // Test currentDirectoryURL cannot be set to nil even though it is a URL?
+        let cwd = URL(fileURLWithPath: FileManager.default.currentDirectoryPath, isDirectory: true)
+        process.currentDirectoryURL = nil
+        XCTAssertNotNil(process.currentDirectoryURL)
+        XCTAssertEqual(process.currentDirectoryURL, cwd)
+
+        let aFileURL = URL(fileURLWithPath: "/a_file", isDirectory: false)
+        XCTAssertFalse(aFileURL.hasDirectoryPath)
+        XCTAssertEqual(aFileURL.path, "/a_file")
+        process.currentDirectoryURL = aFileURL
+        XCTAssertNotEqual(process.currentDirectoryURL, aFileURL)
+        XCTAssertEqual(process.currentDirectoryPath, "/a_file")
+        XCTAssertTrue(try XCTUnwrap(process.currentDirectoryURL).hasDirectoryPath)
+        XCTAssertEqual(try XCTUnwrap(process.currentDirectoryURL).absoluteString, "file:///a_file/")
+
+        let aDirURL = URL(fileURLWithPath: "/a_dir", isDirectory: true)
+        XCTAssertTrue(aDirURL.hasDirectoryPath)
+        XCTAssertEqual(aDirURL.path, "/a_dir")
+        process.currentDirectoryURL = aDirURL
+        XCTAssertEqual(process.currentDirectoryURL, aDirURL)
+        XCTAssertEqual(process.currentDirectoryPath, "/a_dir")
+        XCTAssertTrue(try XCTUnwrap(process.currentDirectoryURL).hasDirectoryPath)
+        XCTAssertEqual(try XCTUnwrap(process.currentDirectoryURL).absoluteString, "file:///a_dir/")
+
+        process.currentDirectoryPath = ""
+        XCTAssertEqual(process.currentDirectoryPath, "")
+        XCTAssertNil(process.currentDirectoryURL)
+        process.currentDirectoryURL = nil
+        XCTAssertEqual(process.currentDirectoryPath, cwd.path)
+
+
         process.executableURL = URL(fileURLWithPath: "/some_file_that_doesnt_exist", isDirectory: false)
         XCTAssertThrowsError(try process.run()) {
             let code = CocoaError.Code(rawValue: ($0 as? NSError)!.code)
@@ -617,13 +649,44 @@ class TestProcess : XCTestCase {
         }
 
         do {
-            try runTask([xdgTestHelperURL().path, "--getcwd"], currentDirectoryPath: "/some_directory_that_doesnt_exsit")
+            let process = Process()
+            process.executableURL = xdgTestHelperURL()
+            process.arguments = [ "--getcwd" ]
+            process.currentDirectoryPath = ""
+
+            let stdoutPipe = Pipe()
+            process.standardOutput = stdoutPipe
+
+            try process.run()
+            process.waitUntilExit()
+
+            guard process.terminationStatus == 0 else {
+                throw Error.TerminationStatus(process.terminationStatus)
+            }
+
+            var stdoutData = Data()
+            #if DARWIN_COMPATIBILITY_TESTS
+                    // Use old API for now
+                    stdoutData.append(stdoutPipe.fileHandleForReading.availableData)
+            #else
+                    if let d = try stdoutPipe.fileHandleForReading.readToEnd() {
+                        stdoutData.append(d)
+                    }
+            #endif
+
+            guard let stdout = String(data: stdoutData, encoding: .utf8) else {
+                throw Error.UnicodeDecodingError(stdoutData)
+            }
+            let directory = stdout.trimmingCharacters(in: CharacterSet(["\n", "\r"]))
+            XCTAssertEqual(directory, FileManager.default.currentDirectoryPath)
         } catch {
+            XCTFail(String(describing: error))
+        }
+
+        XCTAssertThrowsError(try runTask([xdgTestHelperURL().path, "--getcwd"], currentDirectoryPath: "/some_directory_that_doesnt_exsit")) { error in
             let code = CocoaError.Code(rawValue: (error as? NSError)!.code)
             XCTAssertEqual(code, .fileReadNoSuchFile)
-            return
         }
-        XCTFail("Failed to catch error")
     }