### Question:
FileSelectorArrayRow extends JPanel { public static File fallback(File currentDir){ while(!currentDir.exists() && currentDir.getParentFile() != null){ currentDir = currentDir.getParentFile(); } return currentDir; } FileSelectorArrayRow(FileSelectorArrayPanel parent, String url); static File fallback(File currentDir); static String getTextFieldToolTip(); JTextField getTextField();  }### Answer:
@Test @EnabledOnOs(OS.WINDOWS) void testFallback() { final File inputNormal = new File(Directories.getPluginDirectory()); final File inputNormal2 = new File("C:\\Windows"); final File inputNoParent = new File("C:\\"); final File inputNoParentOver = new File("C:\\Usrs"); final File inputNonExistent = new File(Directories.getXdgJrdBaseDir() + File.separator + "plugans"); final File inputNonExistent2 = new File("Z:\\"); final File expectedNormal = new File(Directories.getPluginDirectory()); final File expectedNormal2 = new File("C:\\Windows"); final File expectedNoParent = new File("C:\\"); final File expectedNoParentOver = new File("C:\\"); final File expectedNonExistent = new File(Directories.getXdgJrdBaseDir()); final File expectedNonExistent2 = new File("Z:\\"); assertEquals(expectedNormal, fallback(inputNormal)); assertEquals(expectedNormal2, fallback(inputNormal2)); assertEquals(expectedNoParent, fallback(inputNoParent)); assertEquals(expectedNoParentOver, fallback(inputNoParentOver)); assertEquals(expectedNonExistent, fallback(inputNonExistent)); assertEquals(expectedNonExistent2, fallback(inputNonExistent2)); }
@Test @EnabledOnOs(OS.LINUX) void testFallbackLinux() { final File inputNormal = new File(Directories.getPluginDirectory()); final File inputNormal2 = new File("/sys/kernel"); final File inputNoParent = new File("/"); final File inputNoParentOver = new File("/sys"); final File inputNonExistent = new File(Directories.getXdgJrdBaseDir() + File.separator + "plugans"); final File inputNonExistent2 = Paths.get("./complete/nonsense").normalize().toAbsolutePath().toFile(); final File inputCwd = Paths.get(".").normalize().toAbsolutePath().toFile(); final File expectedNormal = new File(Directories.getPluginDirectory()); final File expectedNormal2 = new File("/sys/kernel"); final File expectedNoParent = new File("/"); final File expectedNoParentOver = new File("/sys"); final File expectedNonExistent = new File(Directories.getXdgJrdBaseDir()); final File expectedNonExistent2 = Paths.get(".").normalize().toAbsolutePath().toFile(); final File expectedCwd = new File(System.getProperty("user.dir")); assertEquals(expectedNormal, fallback(inputNormal)); assertEquals(expectedNormal2, fallback(inputNormal2)); assertEquals(expectedNoParent, fallback(inputNoParent)); assertEquals(expectedNoParentOver, fallback(inputNoParentOver)); assertEquals(expectedNonExistent, fallback(inputNonExistent)); assertEquals(expectedNonExistent2, fallback(inputNonExistent2)); assertEquals(expectedCwd, fallback(inputCwd)); }