fs: throw errors from fs.symlinkSync in JS

PR-URL: #18348
Refs: #18106
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: joyeecheung

lib/fs.js

@@ -1220,6 +1220,7 @@ fs.symlink = function(target, path, type_, callback_) {
   const flags = stringToSymlinkType(type);
   const req = new FSReqWrap();
   req.oncomplete = callback;
+
   binding.symlink(preprocessSymlinkDestination(target, type, path),
                   pathModule.toNamespacedPath(path), flags, req);
 };
@@ -1234,8 +1235,19 @@ fs.symlinkSync = function(target, path, type) {
   validatePath(target, 'target');
   validatePath(path);
   const flags = stringToSymlinkType(type);
-  return binding.symlink(preprocessSymlinkDestination(target, type, path),
-                         pathModule.toNamespacedPath(path), flags);
+
+  const ctx = { path: target, dest: path };
+  binding.symlink(preprocessSymlinkDestination(target, type, path),
+                  pathModule.toNamespacedPath(path), flags, undefined, ctx);
+
+  if (ctx.errno !== undefined) {
+    throw new errors.uvException(ctx);
+  } else if (ctx.error) {
+    // TODO(joyeecheung): this is an encoding error usually caused by memory
+    // problems. We need to figure out proper error code(s) for this.
+    Error.captureStackTrace(ctx.error);
+    throw ctx.error;
+  }
 };
 
 fs.link = function(existingPath, newPath, callback) {

src/node_file.cc

@@ -598,22 +598,26 @@ static void FStat(const FunctionCallbackInfo<Value>& args) {
 static void Symlink(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
 
-  CHECK_GE(args.Length(), 3);
+  int argc = args.Length();
+  CHECK_GE(argc, 4);
 
   BufferValue target(env->isolate(), args[0]);
   CHECK_NE(*target, nullptr);
   BufferValue path(env->isolate(), args[1]);
   CHECK_NE(*path, nullptr);
 
-  CHECK(args[2]->IsUint32());
-  int flags = args[2]->Uint32Value(env->context()).ToChecked();
+  CHECK(args[2]->IsInt32());
+  int flags = args[2].As<Int32>()->Value();
 
   if (args[3]->IsObject()) {  // symlink(target, path, flags, req)
     CHECK_EQ(args.Length(), 4);
     AsyncDestCall(env, args, "symlink", *path, path.length(), UTF8,
                   AfterNoArgs, uv_fs_symlink, *target, *path, flags);
-  } else {  // symlink(target, path, flags)
-    SYNC_DEST_CALL(symlink, *target, *path, *target, *path, flags)
+  } else {  // symlink(target, path, flags, undefinec, ctx)
+    CHECK_EQ(argc, 5);
+    fs_req_wrap req_wrap;
+    SyncCall(env, args[4], &req_wrap, "symlink",
+             uv_fs_symlink, *target, *path, flags);
   }
 }