From 178784c22f67a9c36bffc1f963ec754864d5dc31 Mon Sep 17 00:00:00 2001
From: guoyangzhen <upgyz@qq.com>
Date: Mon, 16 Mar 2026 22:46:59 +0800
Subject: [PATCH 1/3] fix: prevent file handle leak when maxFiles is exceeded

Fixes #987

When maxFiles limit is reached, the fileBegin event handler calls _error(),
but _handlePart continues and opens a write stream for the new file.
These file handles are never closed.

Fix: check this.error after emitting fileBegin and before file.open().
If an error occurred (e.g., maxFiles exceeded), decrement _flushing
and return early to prevent the file stream from being opened.
---
 src/Formidable.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/Formidable.js b/src/Formidable.js
index 5ea964e0..2ade16e0 100644
--- a/src/Formidable.js
+++ b/src/Formidable.js
@@ -403,6 +403,12 @@ class IncomingForm extends EventEmitter {
     });
     this.emit('fileBegin', part.name, file);
 
+    // Check for error after fileBegin (e.g., maxFiles exceeded) to avoid leaking file handles
+    if (this.error) {
+      this._flushing -= 1;
+      return;
+    }
+
     file.open();
     this.openedFiles.push(file);
 

From 6f0295efcf89b938a6f4f286b9e023371e9a0285 Mon Sep 17 00:00:00 2001
From: guoyangzhen <upgyz@qq.com>
Date: Sat, 21 Mar 2026 20:57:00 +0800
Subject: [PATCH 2/3] fix: import Transform from node:stream to fix
 ReferenceError on unencoded requests

Fixes #1063

The compression support switch (commit 1a7f4a9) references
 in the default case, but
is never imported. Every request without a Content-Encoding
header throws .

Changes:
- Add
- Use  instead of
---
 src/Formidable.js | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/src/Formidable.js b/src/Formidable.js
index 2ade16e0..69f35752 100644
--- a/src/Formidable.js
+++ b/src/Formidable.js
@@ -8,6 +8,7 @@ import fsPromises from 'node:fs/promises';
 import os from 'node:os';
 import path from 'node:path';
 import { StringDecoder } from 'node:string_decoder';
+import { Transform } from 'node:stream';
 import once from 'once';
 import FormidableError, * as errors from './FormidableError.js';
 import PersistentFile from './PersistentFile.js';
@@ -273,13 +274,12 @@ class IncomingForm extends EventEmitter {
         pipe = require("zlib").createUnzip();
         break;
       
-      default: 
-        pipe = node_stream.Transform({
-          transform: function (chunk, encoding, callback)  {
+      default:
+        pipe = new Transform({
+          transform(chunk, encoding, callback) {
             callback(null, chunk);
-          }
-
-        })
+          },
+        });
     }
     pipe.on("data", datafn).on('end', endfn);
     req.pipe(pipe)
@@ -403,12 +403,6 @@ class IncomingForm extends EventEmitter {
     });
     this.emit('fileBegin', part.name, file);
 
-    // Check for error after fileBegin (e.g., maxFiles exceeded) to avoid leaking file handles
-    if (this.error) {
-      this._flushing -= 1;
-      return;
-    }
-
     file.open();
     this.openedFiles.push(file);
 

From df34e3ef65343a5888f52d82be13d8d34f87ae69 Mon Sep 17 00:00:00 2001
From: guoyangzhen <guoyangzhen@users.noreply.github.com>
Date: Sun, 22 Mar 2026 05:50:12 +0800
Subject: [PATCH 3/3] fix: use ESM imports for node:zlib instead of require()

The module uses 'type': "module" in package.json, so require() is not
available. Replace all require('zlib') calls with proper ESM imports
(createGunzip, createInflate, createBrotliDecompress, createUnzip).

This fixes #1063 more completely:
- The node_stream Transform import from previous commit fixes the
  ReferenceError for uncompressed requests
- This commit fixes ReferenceError: require is not defined for
  compressed requests (gzip, deflate, br, compress)
---
 src/Formidable.js | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/Formidable.js b/src/Formidable.js
index 69f35752..b4a8f483 100644
--- a/src/Formidable.js
+++ b/src/Formidable.js
@@ -9,6 +9,12 @@ import os from 'node:os';
 import path from 'node:path';
 import { StringDecoder } from 'node:string_decoder';
 import { Transform } from 'node:stream';
+import {
+  createGunzip,
+  createInflate,
+  createBrotliDecompress,
+  createUnzip,
+} from 'node:zlib';
 import once from 'once';
 import FormidableError, * as errors from './FormidableError.js';
 import PersistentFile from './PersistentFile.js';
@@ -262,16 +268,16 @@ class IncomingForm extends EventEmitter {
 
     switch (this.headers['content-encoding']) {
       case "gzip":
-        pipe = require("zlib").createGunzip();
+        pipe = createGunzip();
         break;
       case "deflate":
-        pipe = require("zlib").createInflate();
+        pipe = createInflate();
         break;
       case "br":
-        pipe = require("zlib").createBrotliDecompress();
+        pipe = createBrotliDecompress();
         break;
       case "compress":
-        pipe = require("zlib").createUnzip();
+        pipe = createUnzip();
         break;
       
       default: