From 06178c4dfd14fc7b7280662e7786ce62236b5385 Mon Sep 17 00:00:00 2001
From: Aras Abbasi <aras.abbasi@googlemail.com>
Date: Mon, 8 Sep 2025 18:00:34 +0200
Subject: [PATCH] fix: make error symbols non enumerable

---
 lib/core/errors.js      | 92 ++++++++++++++++++++++++++++++-----------
 lib/mock/mock-errors.js |  4 +-
 2 files changed, 72 insertions(+), 24 deletions(-)

diff --git a/lib/core/errors.js b/lib/core/errors.js
index f8e2d9cb07b..4b1a8a10104 100644
--- a/lib/core/errors.js
+++ b/lib/core/errors.js
@@ -12,7 +12,9 @@ class UndiciError extends Error {
     return instance && instance[kUndiciError] === true
   }
 
-  [kUndiciError] = true
+  get [kUndiciError] () {
+    return true
+  }
 }
 
 const kConnectTimeoutError = Symbol.for('undici.error.UND_ERR_CONNECT_TIMEOUT')
@@ -28,7 +30,9 @@ class ConnectTimeoutError extends UndiciError {
     return instance && instance[kConnectTimeoutError] === true
   }
 
-  [kConnectTimeoutError] = true
+  get [kConnectTimeoutError] () {
+    return true
+  }
 }
 
 const kHeadersTimeoutError = Symbol.for('undici.error.UND_ERR_HEADERS_TIMEOUT')
@@ -44,7 +48,9 @@ class HeadersTimeoutError extends UndiciError {
     return instance && instance[kHeadersTimeoutError] === true
   }
 
-  [kHeadersTimeoutError] = true
+  get [kHeadersTimeoutError] () {
+    return true
+  }
 }
 
 const kHeadersOverflowError = Symbol.for('undici.error.UND_ERR_HEADERS_OVERFLOW')
@@ -60,7 +66,9 @@ class HeadersOverflowError extends UndiciError {
     return instance && instance[kHeadersOverflowError] === true
   }
 
-  [kHeadersOverflowError] = true
+  get [kHeadersOverflowError] () {
+    return true
+  }
 }
 
 const kBodyTimeoutError = Symbol.for('undici.error.UND_ERR_BODY_TIMEOUT')
@@ -76,7 +84,9 @@ class BodyTimeoutError extends UndiciError {
     return instance && instance[kBodyTimeoutError] === true
   }
 
-  [kBodyTimeoutError] = true
+  get [kBodyTimeoutError] () {
+    return true
+  }
 }
 
 const kInvalidArgumentError = Symbol.for('undici.error.UND_ERR_INVALID_ARG')
@@ -92,7 +102,9 @@ class InvalidArgumentError extends UndiciError {
     return instance && instance[kInvalidArgumentError] === true
   }
 
-  [kInvalidArgumentError] = true
+  get [kInvalidArgumentError] () {
+    return true
+  }
 }
 
 const kInvalidReturnValueError = Symbol.for('undici.error.UND_ERR_INVALID_RETURN_VALUE')
@@ -108,7 +120,9 @@ class InvalidReturnValueError extends UndiciError {
     return instance && instance[kInvalidReturnValueError] === true
   }
 
-  [kInvalidReturnValueError] = true
+  get [kInvalidReturnValueError] () {
+    return true
+  }
 }
 
 const kAbortError = Symbol.for('undici.error.UND_ERR_ABORT')
@@ -124,7 +138,9 @@ class AbortError extends UndiciError {
     return instance && instance[kAbortError] === true
   }
 
-  [kAbortError] = true
+  get [kAbortError] () {
+    return true
+  }
 }
 
 const kRequestAbortedError = Symbol.for('undici.error.UND_ERR_ABORTED')
@@ -140,7 +156,9 @@ class RequestAbortedError extends AbortError {
     return instance && instance[kRequestAbortedError] === true
   }
 
-  [kRequestAbortedError] = true
+  get [kRequestAbortedError] () {
+    return true
+  }
 }
 
 const kInformationalError = Symbol.for('undici.error.UND_ERR_INFO')
@@ -156,7 +174,9 @@ class InformationalError extends UndiciError {
     return instance && instance[kInformationalError] === true
   }
 
-  [kInformationalError] = true
+  get [kInformationalError] () {
+    return true
+  }
 }
 
 const kRequestContentLengthMismatchError = Symbol.for('undici.error.UND_ERR_REQ_CONTENT_LENGTH_MISMATCH')
@@ -172,7 +192,9 @@ class RequestContentLengthMismatchError extends UndiciError {
     return instance && instance[kRequestContentLengthMismatchError] === true
   }
 
-  [kRequestContentLengthMismatchError] = true
+  get [kRequestContentLengthMismatchError] () {
+    return true
+  }
 }
 
 const kResponseContentLengthMismatchError = Symbol.for('undici.error.UND_ERR_RES_CONTENT_LENGTH_MISMATCH')
@@ -188,7 +210,9 @@ class ResponseContentLengthMismatchError extends UndiciError {
     return instance && instance[kResponseContentLengthMismatchError] === true
   }
 
-  [kResponseContentLengthMismatchError] = true
+  get [kResponseContentLengthMismatchError] () {
+    return true
+  }
 }
 
 const kClientDestroyedError = Symbol.for('undici.error.UND_ERR_DESTROYED')
@@ -204,7 +228,9 @@ class ClientDestroyedError extends UndiciError {
     return instance && instance[kClientDestroyedError] === true
   }
 
-  [kClientDestroyedError] = true
+  get [kClientDestroyedError] () {
+    return true
+  }
 }
 
 const kClientClosedError = Symbol.for('undici.error.UND_ERR_CLOSED')
@@ -220,7 +246,9 @@ class ClientClosedError extends UndiciError {
     return instance && instance[kClientClosedError] === true
   }
 
-  [kClientClosedError] = true
+  get [kClientClosedError] () {
+    return true
+  }
 }
 
 const kSocketError = Symbol.for('undici.error.UND_ERR_SOCKET')
@@ -237,7 +265,9 @@ class SocketError extends UndiciError {
     return instance && instance[kSocketError] === true
   }
 
-  [kSocketError] = true
+  get [kSocketError] () {
+    return true
+  }
 }
 
 const kNotSupportedError = Symbol.for('undici.error.UND_ERR_NOT_SUPPORTED')
@@ -253,7 +283,9 @@ class NotSupportedError extends UndiciError {
     return instance && instance[kNotSupportedError] === true
   }
 
-  [kNotSupportedError] = true
+  get [kNotSupportedError] () {
+    return true
+  }
 }
 
 const kBalancedPoolMissingUpstreamError = Symbol.for('undici.error.UND_ERR_BPL_MISSING_UPSTREAM')
@@ -269,7 +301,9 @@ class BalancedPoolMissingUpstreamError extends UndiciError {
     return instance && instance[kBalancedPoolMissingUpstreamError] === true
   }
 
-  [kBalancedPoolMissingUpstreamError] = true
+  get [kBalancedPoolMissingUpstreamError] () {
+    return true
+  }
 }
 
 const kHTTPParserError = Symbol.for('undici.error.UND_ERR_HTTP_PARSER')
@@ -285,7 +319,9 @@ class HTTPParserError extends Error {
     return instance && instance[kHTTPParserError] === true
   }
 
-  [kHTTPParserError] = true
+  get [kHTTPParserError] () {
+    return true
+  }
 }
 
 const kResponseExceededMaxSizeError = Symbol.for('undici.error.UND_ERR_RES_EXCEEDED_MAX_SIZE')
@@ -301,7 +337,9 @@ class ResponseExceededMaxSizeError extends UndiciError {
     return instance && instance[kResponseExceededMaxSizeError] === true
   }
 
-  [kResponseExceededMaxSizeError] = true
+  get [kResponseExceededMaxSizeError] () {
+    return true
+  }
 }
 
 const kRequestRetryError = Symbol.for('undici.error.UND_ERR_REQ_RETRY')
@@ -320,7 +358,9 @@ class RequestRetryError extends UndiciError {
     return instance && instance[kRequestRetryError] === true
   }
 
-  [kRequestRetryError] = true
+  get [kRequestRetryError] () {
+    return true
+  }
 }
 
 const kResponseError = Symbol.for('undici.error.UND_ERR_RESPONSE')
@@ -339,7 +379,9 @@ class ResponseError extends UndiciError {
     return instance && instance[kResponseError] === true
   }
 
-  [kResponseError] = true
+  get [kResponseError] () {
+    return true
+  }
 }
 
 const kSecureProxyConnectionError = Symbol.for('undici.error.UND_ERR_PRX_TLS')
@@ -356,7 +398,9 @@ class SecureProxyConnectionError extends UndiciError {
     return instance && instance[kSecureProxyConnectionError] === true
   }
 
-  [kSecureProxyConnectionError] = true
+  get [kSecureProxyConnectionError] () {
+    return true
+  }
 }
 
 const kMaxOriginsReachedError = Symbol.for('undici.error.UND_ERR_MAX_ORIGINS_REACHED')
@@ -372,7 +416,9 @@ class MaxOriginsReachedError extends UndiciError {
     return instance && instance[kMaxOriginsReachedError] === true
   }
 
-  [kMaxOriginsReachedError] = true
+  get [kMaxOriginsReachedError] () {
+    return true
+  }
 }
 
 module.exports = {
diff --git a/lib/mock/mock-errors.js b/lib/mock/mock-errors.js
index c0c504b4b45..69e4f9cc371 100644
--- a/lib/mock/mock-errors.js
+++ b/lib/mock/mock-errors.js
@@ -19,7 +19,9 @@ class MockNotMatchedError extends UndiciError {
     return instance && instance[kMockNotMatchedError] === true
   }
 
-  [kMockNotMatchedError] = true
+  get [kMockNotMatchedError] () {
+    return true
+  }
 }
 
 module.exports = {