Implement the chmod method in FileHandle class

Author: nkaradzhov

ext/node/polyfills/_fs/_fs_open.ts

@@ -153,7 +153,7 @@ export function openPromise(
   return new Promise((resolve, reject) => {
     open(path, flags, mode, (err, fd) => {
       if (err) reject(err);
-      else resolve(new FileHandle(fd));
+      else resolve(new FileHandle(fd, path));
     });
   });
 }

ext/node/polyfills/internal/fs/handle.ts

@@ -5,7 +5,7 @@
 
 import { EventEmitter } from "node:events";
 import { Buffer } from "node:buffer";
-import { promises, read, write } from "node:fs";
+import { promises, read, write }  from "node:fs";
 export type { BigIntStats, Stats } from "ext:deno_node/_fs/_fs_stat.ts";
 import {
   BinaryOptionsArgument,
@@ -26,11 +26,15 @@ interface ReadResult {
   buffer: Buffer;
 }
 
+type Path =string | Buffer | URL;
 export class FileHandle extends EventEmitter {
   #rid: number;
-  constructor(rid: number) {
+  #path: Path
+
+  constructor(rid: number, path: Path) {
     super();
     this.#rid = rid;
+    this.#path = path;
   }
 
   get fd() {
@@ -144,17 +148,24 @@ export class FileHandle extends EventEmitter {
   stat(options?: { bigint: boolean }): Promise<Stats | BigIntStats> {
     return fsCall(promises.fstat, this, options);
   }
+  chmod(mode: number): Promise<void> {
+    assertNotClosed(this, promises.chmod.name)
+    return promises.chmod(this.#path, mode)
+  }
 }
 
-function fsCall(fn, handle, ...args) {
+function assertNotClosed(handle: FileHandle, syscall: string) {
   if (handle.fd === -1) {
     const err = new Error("file closed");
     throw Object.assign(err, {
       code: "EBADF",
-      syscall: fn.name,
+      syscall
     });
   }
+}
 
+function fsCall(fn, handle, ...args) {
+  assertNotClosed(handle, fn.name)
   return fn(handle.fd, ...args);
 }
 

tests/unit_node/_fs/_fs_handle_test.ts

@@ -199,3 +199,14 @@ Deno.test(
     assertEquals(data.length, 0);
   },
 );
+
+Deno.test("chmod", async function () {
+  const fileHandle = await fs.open(testData);
+  await fileHandle.chmod(0o666)
+  const info1 = await Deno.stat(testData)
+  assertEquals(info1.mode?.toString(8), `100666`)
+  await fileHandle.chmod(0o555)
+  const info2 = await Deno.stat(testData)
+  assertEquals(info2.mode?.toString(8), `100555`)
+  await fileHandle.close();
+});