🐛 Allow callFollowingErrorInterceptor when rejecting in ErrorInterceptorHandler

dio/CHANGELOG.md

@@ -11,6 +11,7 @@ See the [Migration Guide][] for the complete breaking changes list.**
   On web, timeout handling is best-effort because synchronous JavaScript work cannot be preempted.
 - Fix `FormData.clone()` dropping `boundaryName` and `camelCaseContentDisposition`, so a retried multipart request now keeps the original options instead of silently falling back to the defaults.
 - Fix `QueuedInterceptor` stalling its queue forever when the active request is cancelled while its callback is still pending (never calls `next`/`resolve`/`reject`), which blocked every subsequent request routed through the interceptor.
+- Fix `ErrorInterceptorHandler.reject(..., true)` not continuing to following error interceptors in queued interceptors.
 
 ## 5.9.2
 

dio/lib/src/interceptor.dart

@@ -178,10 +178,24 @@ class ErrorInterceptorHandler extends _BaseHandler {
   }
 
   /// Completes the request by reject with the [error] as the result.
-  void reject(DioException error) {
+  ///
+  /// Invoking the method will make the rest of interceptors in the queue
+  /// skipped to handle the request,
+  /// unless [callFollowingErrorInterceptor] is true
+  /// which delivers [InterceptorResultType.rejectCallFollowing]
+  /// to the [InterceptorState].
+  void reject(
+    DioException error, [
+    bool callFollowingErrorInterceptor = false,
+  ]) {
     _throwIfCompleted();
     _completer.completeError(
-      InterceptorState<DioException>(error, InterceptorResultType.reject),
+      InterceptorState<DioException>(
+        error,
+        callFollowingErrorInterceptor
+            ? InterceptorResultType.rejectCallFollowing
+            : InterceptorResultType.reject,
+      ),
       error.stackTrace,
     );
     _processNextInQueue?.call();

dio/test/interceptor_test.dart

@@ -844,6 +844,39 @@ void main() {
       expect(tokenRequestCounts, 1);
       expect(result, 3);
     });
+
+    test(
+      'error interceptor reject with callFollowingErrorInterceptor continues',
+      () async {
+        final dio = Dio()
+          ..options.baseUrl = MockAdapter.mockBase
+          ..httpClientAdapter = MockAdapter();
+
+        dio.interceptors
+          ..add(
+            QueuedInterceptorsWrapper(
+              onError: (error, handler) {
+                handler.reject(error.copyWith(error: 1), true);
+              },
+            ),
+          )
+          ..add(
+            QueuedInterceptorsWrapper(
+              onError: (error, handler) {
+                final count = error.error as int;
+                handler.next(error.copyWith(error: count + 1));
+              },
+            ),
+          );
+
+        expect(
+          dio
+              .get('/test-not-found')
+              .catchError((e) => throw (e as DioException).error as int),
+          throwsA(2),
+        );
+      },
+    );
   });
 
   group('LogInterceptor', () {