fs: check subdir correct in cpSync

Author: jazelly

src/node_file.cc

@@ -3193,7 +3193,7 @@ static void CpSyncCheckPaths(const FunctionCallbackInfo<Value>& args) {
 
  std::string dest_path_str = dest_path.string();
  // Check if dest_path is a subdirectory of src_path.
- if (src_is_dir && dest_path_str.starts_with(src_path.string())) {
+ if (src_is_dir && dest_path.parent_path().string().starts_with(src_path.string())) {
  std::string message = "Cannot copy " + src_path.string() +
  " to a subdirectory of self " + dest_path.string();
  return THROW_ERR_FS_CP_EINVAL(env, message.c_str());

test/parallel/test-fs-cp.mjs

@@ -24,8 +24,8 @@ import tmpdir from '../common/tmpdir.js';
 tmpdir.refresh();
 
 let dirc = 0;
-function nextdir() {
- return tmpdir.resolve(`copy_${++dirc}`);
+function nextdir(dirname) {
+ return tmpdir.resolve(dirname || `copy_${++dirc}`);
 }
 
 // Synchronous implementation of copy.
@@ -312,6 +312,17 @@ function nextdir() {
  );
 }
 
+// It must not throw error if attempt is made to copy to dest
+// directory with same prefix as src directory
+// regression test for https://github.com/nodejs/node/issues/54285
+{
+ const src = nextdir('prefix');
+ const dest = nextdir('prefix-a');
+ mkdirSync(src);
+ mkdirSync(dest);
+ cpSync(src, dest, { recursive: true });
+}
+
 // It throws error if attempt is made to copy to subdirectory of self.
 {
  const src = './test/fixtures/copy/kitchen-sink';