Fail existing

Author: brianquinlan

pkgs/io_file/lib/src/vm_posix_file_system.dart

@@ -322,7 +322,7 @@ final class PosixFileSystem extends FileSystem {
       final newFd = _tempFailureRetry(
         () => libc.open(
           newPath.toNativeUtf8(allocator: arena).cast(),
-          libc.O_WRONLY | libc.O_TRUNC | libc.O_CREAT | libc.O_CLOEXEC,
+          libc.O_WRONLY | libc.O_CREAT | libc.O_EXCL | libc.O_CLOEXEC,
           _defaultMode,
         ),
       );

pkgs/io_file/lib/src/vm_windows_file_system.dart

@@ -462,8 +462,8 @@ final class WindowsFileSystem extends FileSystem {
         win32.FILE_GENERIC_WRITE,
         0,
         nullptr,
-        win32.CREATE_ALWAYS,
-        win32.FILE_ATTRIBUTE_NORMAL,
+        win32.CREATE_NEW,
+        win32.FILE_ATTRIBUTE_NORMAL & win32.FILE_FLAG_OPEN_REPARSE_POINT,
         0,
       );
       if (newHandle == win32.INVALID_HANDLE_VALUE) {

pkgs/io_file/test/copy_file_test.dart

@@ -111,19 +111,55 @@ void main() {
       expect(io.File(newPath).readAsBytesSync(), data);
     });
 
-    test('copy file to existing', () {
+    test('copy file to existing file', () {
       final data = randomUint8List(1024);
       final oldPath = '$tmp/file1';
       final newPath = '$tmp/file2';
       io.File(oldPath).writeAsBytesSync(data);
       io.File(newPath).writeAsStringSync('Hello World!');
 
-      fileSystem.copyFile(oldPath, newPath);
+      expect(
+        () => fileSystem.copyFile(oldPath, newPath),
+        throwsA(
+          isA<PathExistsException>()
+              .having((e) => e.path1, 'path1', newPath)
+              .having(
+                (e) => e.errorCode,
+                'errorCode',
+                io.Platform.isWindows
+                    ? win32.ERROR_ALREADY_EXISTS
+                    : errors.eexist,
+              ),
+        ),
+      );
+    });
 
-      expect(io.File(newPath).readAsBytesSync(), data);
+    test('copy file to existing link', () {
+      final data = randomUint8List(1024);
+      final oldPath = '$tmp/file1';
+      final linkedFile = '$tmp/file2';
+      final newPath = '$tmp/link';
+      io.File(oldPath).writeAsBytesSync(data);
+      io.File(linkedFile).writeAsStringSync('Hello World');
+      io.Link(newPath).createSync(linkedFile);
+
+      expect(
+        () => fileSystem.copyFile(oldPath, newPath),
+        throwsA(
+          isA<PathExistsException>()
+              .having((e) => e.path1, 'path1', newPath)
+              .having(
+                (e) => e.errorCode,
+                'errorCode',
+                io.Platform.isWindows
+                    ? win32.ERROR_ALREADY_EXISTS
+                    : errors.eexist,
+              ),
+        ),
+      );
     });
 
-    test('copy to existant directory', () {
+    test('copy to existing directory', () {
       final data = randomUint8List(1024);
       final oldPath = '$tmp/file1';
       final newPath = '$tmp/file2';
@@ -133,13 +169,15 @@ void main() {
       expect(
         () => fileSystem.copyFile(oldPath, newPath),
         throwsA(
-          isA<IOFileException>().having(
-            (e) => e.errorCode,
-            'errorCode',
-            io.Platform.isWindows
-                ? 5 // ERROR_ACCESS_DENIED
-                : 21, // EISDIR
-          ),
+          isA<PathExistsException>()
+              .having((e) => e.path1, 'path1', newPath)
+              .having(
+                (e) => e.errorCode,
+                'errorCode',
+                io.Platform.isWindows
+                    ? win32.ERROR_ALREADY_EXISTS
+                    : errors.eexist,
+              ),
         ),
       );
     });