feat: FileHandle.writeFile

Author: merceyz

packages/yarnpkg-fslib/sources/patchFs/FileHandle.ts

@@ -199,7 +199,8 @@ export class FileHandle<P extends Path> {
     data: string | Uint8Array,
     options?: (ObjectEncodingOptions & FlagAndOpenMode & Abortable) | BufferEncoding | null,
   ): Promise<void> {
-    throw new Error(`Method not implemented.`);
+    const encoding = (typeof options === `string` ? options : options?.encoding) ?? undefined;
+    return this._baseFs.writeFilePromise(this.fd, data, encoding);
   }
 
   async write(...args: WriteArgsString): Promise<{ bytesWritten: number, buffer: string }>

packages/yarnpkg-fslib/tests/patchedFs.test.ts

@@ -341,6 +341,21 @@ describe(`patchedFs`, () => {
     });
   });
 
+  it(`should support FileHandle.writeFile`, async () => {
+    const patchedFs = extendFs(fs, new PosixFS(new NodeFS()));
+
+    await xfs.mktempPromise(async dir => {
+      const filepath = npath.join(npath.fromPortablePath(dir), `foo.txt`);
+
+      const fd = await patchedFs.promises.open(filepath, `w`);
+      await fd.writeFile(`foo`);
+      await fd.writeFile(`bar`);
+      await fd.close();
+
+      await expect(patchedFs.promises.readFile(filepath, `utf8`)).resolves.toEqual(`foobar`);
+    });
+  });
+
   it(`should support FileHandle.appendFile`, async () => {
     const patchedFs = extendFs(fs, new PosixFS(new NodeFS()));