1 files changed, 11 insertions, 0 deletions
diff --git a/node_modules/undici/lib/mock/mock-errors.js b/node_modules/undici/lib/mock/mock-errors.js
index 5442c0e..3de5603 100644
--- a/node_modules/undici/lib/mock/mock-errors.js
+++ b/node_modules/undici/lib/mock/mock-errors.js
@@ -2,6 +2,11 @@
 
 const { UndiciError } = require('../core/errors')
 
+const kMockNotMatchedError = Symbol.for('undici.error.UND_MOCK_ERR_MOCK_NOT_MATCHED')
+
+/**
+ * The request does not match any registered mock dispatches.
+ */
 class MockNotMatchedError extends UndiciError {
   constructor (message) {
     super(message)
@@ -10,6 +15,12 @@ class MockNotMatchedError extends UndiciError {
     this.message = message || 'The request does not match any registered mock dispatches'
     this.code = 'UND_MOCK_ERR_MOCK_NOT_MATCHED'
   }
+
+  static [Symbol.hasInstance] (instance) {
+    return instance && instance[kMockNotMatchedError] === true
+  }
+
+  [kMockNotMatchedError] = true
 }
 
 module.exports = {