Several fixes for File.extract

Tweaks and fixes.

src/reader.zig

@@ -80,8 +80,6 @@ pub const Reader = struct {
 
 test "root iter" {
     const test_sfs_path = "testing/LinuxPATest.sfs";
-    // const test_file_path = "PortableApps/PortableApps.com/Data/PortableAppsMenu.ini";
-
     var rdr: Reader = try .init(std.testing.allocator, test_sfs_path, 0);
     defer rdr.deinit();
     var rootIter = try rdr.root.iterator(&rdr);
@@ -90,3 +88,12 @@ test "root iter" {
         std.debug.print("{s}\n", .{f.name});
     }
 }
+
+test "extract" {
+    const test_sfs_path = "testing/LinuxPATest.sfs";
+    const extract_path = "testing/testExtract";
+    try std.fs.cwd().deleteTree(extract_path);
+    var rdr: Reader = try .init(std.testing.allocator, test_sfs_path, 0);
+    defer rdr.deinit();
+    try rdr.root.extract(&rdr, extract_path);
+}