fixup! lib: aggregate errors to avoid error swallowing

Author: aduh95

lib/internal/errors.js

@@ -146,10 +146,12 @@ const aggregateTwoErrors = hideStackFrames((innerError, outerError) => {
       return outerError;
     }
     // eslint-disable-next-line no-restricted-syntax
-    return new AggregateError(new SafeArrayIterator([
+    const err = new AggregateError(new SafeArrayIterator([
       outerError,
       innerError,
     ]), outerError.message);
+    err.code = outerError.code;
+    return err;
   }
   return innerError || outerError;
 });

test/parallel/test-error-aggregateTwoErrors.js

@@ -21,8 +21,12 @@ assert.strictEqual(aggregateTwoErrors(null, null), null);
   const err0 = new Error('original');
   const err1 = new Error('second error');
 
+  err0.code = 'ERR0';
+  err1.code = 'ERR1';
+
   const chainedError = aggregateTwoErrors(err1, err0);
   assert.strictEqual(chainedError.message, err0.message);
+  assert.strictEqual(chainedError.code, err0.code);
   assert.deepStrictEqual(chainedError.errors, [err0, err1]);
 }
 
@@ -31,16 +35,25 @@ assert.strictEqual(aggregateTwoErrors(null, null), null);
   const err1 = new Error('second error');
   const err2 = new Error('third error');
 
+  err0.code = 'ERR0';
+  err1.code = 'ERR1';
+  err2.code = 'ERR2';
+  
   const chainedError = aggregateTwoErrors(err2, aggregateTwoErrors(err1, err0));
   assert.strictEqual(chainedError.message, err0.message);
+  assert.strictEqual(chainedError.code, err0.code);
   assert.deepStrictEqual(chainedError.errors, [err0, err1, err2]);
 }
 
 {
   const err0 = new Error('original');
   const err1 = new Error('second error');
 
+  err0.code = 'ERR0';
+  err1.code = 'ERR1';
+
   const chainedError = aggregateTwoErrors(null, aggregateTwoErrors(err1, err0));
   assert.strictEqual(chainedError.message, err0.message);
+  assert.strictEqual(chainedError.code, err0.code);
   assert.deepStrictEqual(chainedError.errors, [err0, err1]);
 }