Custom error cloning to fix node v21 issue

lib/clone.js

@@ -88,6 +88,12 @@ module.exports = internals.clone = function (obj, options = {}, _seen = null) {
             continue;
         }
 
+        if (baseProto === Types.error &&
+            (key === 'message' || key === 'stack')) {
+
+            continue;       // Already a part of the base object
+        }
+
         const descriptor = Object.getOwnPropertyDescriptor(obj, key);
         if (descriptor) {
             if (descriptor.get ||
@@ -162,6 +168,14 @@ internals.base = function (obj, baseProto, options) {
 
         return newObj;
     }
+    else if (baseProto === Types.error) {
+        const err = structuredClone(obj);                    // Needed to copy internal stack state
+        if (proto !== baseProto) {
+            Object.setPrototypeOf(err, proto);               // Fix prototype
+        }
+
+        return err;
+    }
 
     if (internals.needsProtoHack.has(baseProto)) {
         const newObj = new proto.constructor();

test/clone.js

@@ -680,6 +680,34 @@ describe('clone()', () => {
         expect(b.get(nestedObj)).to.equal(a.get(nestedObj));
     });
 
+    it('clones Error', () => {
+
+        class CustomError extends Error {
+            name = 'CustomError';
+        }
+
+        const a = new CustomError('bad');
+        a.test = Symbol('test');
+
+        const b = Hoek.clone(a);
+
+        expect(b).to.equal(a);
+        expect(b).to.not.shallow.equal(a);
+        expect(b).to.be.instanceOf(CustomError);
+        expect(b.stack).to.equal(a.stack);     // Explicitly validate the .stack getters
+    });
+
+    it('cloned Error handles late stack update', () => {
+
+        const a = new Error('bad');
+        const b = Hoek.clone(a);
+
+        a.stack = 'late update';
+
+        expect(b).to.equal(a);
+        expect(b.stack).to.not.equal(a.stack);
+    });
+
     it('ignores symbols', () => {
 
         const sym = Symbol();